The rise of multi-cloud systems has been spurred.For safety-critical missions,it is important to guarantee their security and reliability.To address trust constraints in a heterogeneous multi-cloud environment,this wo...The rise of multi-cloud systems has been spurred.For safety-critical missions,it is important to guarantee their security and reliability.To address trust constraints in a heterogeneous multi-cloud environment,this work proposes a novel scheduling method called matching and multi-round allocation(MMA)to optimize the makespan and total cost for all submitted tasks subject to security and reliability constraints.The method is divided into two phases for task scheduling.The first phase is to find the best matching candidate resources for the tasks to meet their preferential demands including performance,security,and reliability in a multi-cloud environment;the second one iteratively performs multiple rounds of re-allocating to optimize tasks execution time and cost by minimizing the variance of the estimated completion time.The proposed algorithm,the modified cuckoo search(MCS),hybrid chaotic particle search(HCPS),modified artificial bee colony(MABC),max-min,and min-min algorithms are implemented in CloudSim to create simulations.The simulations and experimental results show that our proposed method achieves shorter makespan,lower cost,higher resource utilization,and better trade-off between time and economic cost.It is more stable and efficient.展开更多
Cloud computingmakes dynamic resource provisioning more accessible.Monitoring a functioning service is crucial,and changes are made when particular criteria are surpassed.This research explores the decentralized multi...Cloud computingmakes dynamic resource provisioning more accessible.Monitoring a functioning service is crucial,and changes are made when particular criteria are surpassed.This research explores the decentralized multi-cloud environment for allocating resources and ensuring the Quality of Service(QoS),estimating the required resources,and modifying allotted resources depending on workload and parallelism due to resources.Resource allocation is a complex challenge due to the versatile service providers and resource providers.The engagement of different service and resource providers needs a cooperation strategy for a sustainable quality of service.The objective of a coherent and rational resource allocation is to attain the quality of service.It also includes identifying critical parameters to develop a resource allocation mechanism.A framework is proposed based on the specified parameters to formulate a resource allocation process in a decentralized multi-cloud environment.The three main parameters of the proposed framework are data accessibility,optimization,and collaboration.Using an optimization technique,these three segments are further divided into subsets for resource allocation and long-term service quality.The CloudSim simulator has been used to validate the suggested framework.Several experiments have been conducted to find the best configurations suited for enhancing collaboration and resource allocation to achieve sustained QoS.The results support the suggested structure for a decentralized multi-cloud environment and the parameters that have been determined.展开更多
Cloud computing technology is favored by users because of its strong computing power and convenient services.At the same time,scheduling performance has an extremely efficient impact on promoting carbon neutrality.Cur...Cloud computing technology is favored by users because of its strong computing power and convenient services.At the same time,scheduling performance has an extremely efficient impact on promoting carbon neutrality.Currently,scheduling research in the multi-cloud environment aims to address the challenges brought by business demands to cloud data centers during peak hours.Therefore,the scheduling problem has promising application prospects under themulti-cloud environment.This paper points out that the currently studied scheduling problems in the multi-cloud environment mainly include independent task scheduling and workflow task scheduling based on the dependencies between tasks.This paper reviews the concepts,types,objectives,advantages,challenges,and research status of task scheduling in the multi-cloud environment.Task scheduling strategies proposed in the existing related references are analyzed,discussed,and summarized,including research motivation,optimization algorithm,and related objectives.Finally,the research status of the two kinds of task scheduling is compared,and several future important research directions of multi-cloud task scheduling are proposed.展开更多
One of the fundamental problems associated with scheduling workflows on virtual machines in a multi-cloud environment is how to find a near-optimum permutation.The workflow scheduling involves assigning independent co...One of the fundamental problems associated with scheduling workflows on virtual machines in a multi-cloud environment is how to find a near-optimum permutation.The workflow scheduling involves assigning independent computational jobs with conflicting objectives to a set of virtual machines.Most optimization methods for solving non-deterministic polynomial-time hardness(NP-hard)problems deploy multi-objective algorithms.As such,Pareto dominance is one of the most efficient criteria for determining the best solutions within the Pareto front.However,the main drawback of this method is that it requires a reasonably long time to provide an optimum solution.In this paper,a new multi-objective minimum weight algorithm is used to derive the Pareto front.The conflicting objectives considered are reliability,cost,resource utilization,risk probability and makespan.Because multi-objective algorithms select a number of permutations with an optimal trade-off between conflicting objectives,we propose a new decisionmaking approach named the minimum weight optimization(MWO).MWO produces alternative weight to determine the inertia weight by using an adaptive strategy to provide an appropriate alternative for all optimal solutions.This way,consumers’needs and service providers’interests are taken into account.Using standard scientific workflows with conflicting objectives,we compare our proposed multi-objective scheduling algorithm using minimum weigh optimization(MOS-MWO)with multi-objective scheduling algorithm(MOS).Results show that MOS-MWO outperforms MOS in term of QoS satisfaction rate.展开更多
Due to the need for massive device connectivity,low communication latency,and various customizations in 6G architecture,a distributed cloud deployment approach will be more relevant to the space-air-ground-sea integra...Due to the need for massive device connectivity,low communication latency,and various customizations in 6G architecture,a distributed cloud deployment approach will be more relevant to the space-air-ground-sea integrated network scenario.However,the openness and heterogeneity of the 6G network cause the problems of network security.To improve the trustworthiness of 6G networks,we propose a trusted computing-based approach for establishing trust relationships inmulti-cloud scenarios.The proposed method shows the relationship of trust based on dual-level verification.It separates the trustworthy states of multiple complex cloud units in 6G architecture into the state within and between cloud units.Firstly,SM3 algorithm establishes the chain of trust for the system’s trusted boot phase.Then,the remote attestation server(RAS)of distributed cloud units verifies the physical servers.Meanwhile,the physical servers use a ring approach to verify the cloud servers.Eventually,the centralized RAS takes one-time authentication to the critical evidence information of distributed cloud unit servers.Simultaneously,the centralized RAS also verifies the evidence of distributed RAS.We establish our proposed approach in a natural OpenStack-based cloud environment.The simulation results show that the proposed method achieves higher security with less than a 1%system performance loss.展开更多
The benefits of cloud storage come along with challenges and open issues about availability of services, vendor lock-in and data security, etc. One solution to mitigate the problems is the multi-cloud storage, where t...The benefits of cloud storage come along with challenges and open issues about availability of services, vendor lock-in and data security, etc. One solution to mitigate the problems is the multi-cloud storage, where the selection of service providers is a key point. In this paper, an algorithm that can select optimal provider subset for data placement among a set of providers in multicloud storage architecture based on IDA is proposed, designed to achieve good tradeoff among storage cost, algorithm cost, vendor lock-in, transmission performance and data availability. Experiments demonstrate that it is efficient and accurate to find optimal solutions in reasonable amount of time, using parameters taken from real cloud providers.展开更多
The purpose of this paper is to provide a better knowledge of the cloud computing as well as to suggest relevant research paths in this growing field. Also, we will go through the future benefits of cloud computing an...The purpose of this paper is to provide a better knowledge of the cloud computing as well as to suggest relevant research paths in this growing field. Also, we will go through the future benefits of cloud computing and the upcoming possible challenges we will have. Intext Cloud, performance, cloud computing, architecture, scale-up, and big data are all terms used in this context. Cloud computing offers a wide range of architectural configurations, including the number of processors, memory, and nodes. Cloud computing has already changed the way we store, process, and access data, and it is expected to continue to have a significant impact on the future of information technology. Cloud computing enables organizations to scale their IT resources up or down quickly and easily, without the need for costly hardware upgrades. This can help organizations to respond more quickly to changing business needs and market conditions. By moving IT resources to the cloud, organizations can reduce their IT infrastructure costs and improve their operational efficiency. Cloud computing also allows organizations to pay only for the resources they use, rather than investing in expensive hardware and software licenses. Cloud providers invest heavily in security and compliance measures, which can help to protect organizations from cyber threats and ensure regulatory compliance. Cloud computing provides a scalable platform for AI and machine learning applications, enabling organizations to build and deploy these technologies more easily and cost-effectively. A task, an application, and its input can take up to 20 times longer or cost 10 times more than optimal. Cloud products’ ready adaptability has resulted in a paradigm change. Previously, an application was optimized for a specific cluster;however, in the cloud, the architectural configuration is tuned for the workload. The evolution of cloud computing from the era of mainframes and dumb terminals has been significant, but there are still many advancements to come. As we look towards the future, IT leaders and the companies they serve will face increasingly complex challenges in order to stay competitive in a constantly evolving cloud computing landscape. Additionally, it will be crucial to remain compliant with existing regulations as well as new regulations that may emerge in the future. It is safe to say that the next decade of cloud computing will be just as dramatic as the last where many internet services are becoming cloud-based, and huge enterprises will struggle to fund physical infrastructure. Cloud computing is significantly used in business innovation and because of its agility and adaptability, cloud technology enables new ways of working, operating, and running a business. The service enables users to access files and applications stored in the cloud from anywhere, removing the requirement for users to be always physically close to actual hardware. Cloud computing makes the connection available from anywhere because they are kept on a network of hosted computers that carry data over the internet. Cloud computing has shown to be advantageous to both consumers and corporations. To be more specific, the cloud has altered our way of life. Overall, cloud computing is likely to continue to play a significant role in the future of IT, enabling organizations to become more agile, efficient, and innovative in the face of rapid technological change. This is likely to drive further innovation in AI and machine learning in the coming years.展开更多
High-copy integration of key genes offers a promising strategy for efficient biosynthesis of valuable natural products in Saccharomyces cerevisiae.However,traditional multi-copy gene integration methods meet challenge...High-copy integration of key genes offers a promising strategy for efficient biosynthesis of valuable natural products in Saccharomyces cerevisiae.However,traditional multi-copy gene integration methods meet challenges including low efficiency and labor-intensive screening processes.In this study,we developed the IMIGE(Iterative Multi-copy Integration by Gene Editing)system,a CRISPR/Cas9-based approach that exploits bothδand rDNA repetitive sequences for simultaneous multi-copy integrations in S.cerevisiae.This system combines the mixture of Cas9-sgRNA expression vectors with a split-marker strategy for efficient donor DNA assembly in vivo and enables rapid,iterative screening through growth-related phenotypes.When applied to the biosynthesis of ergothioneine and cordycepin,the IMIGE system achieved significant yield improvements,with titers of 105.31±1.53 mg/L and 62.01±2.4 mg/L,respectively,within just two screening cycles(5.5-6 days in total).These yields represent increases of 407.39%and 222.13%,respectively,compared to the strains with episomal expression.By streamlining the integration process,utilizing growth-based selection,and minimizing screening demands in both equipment and labor,the IMIGE system could provide an efficient and scalable platform for high-throughput strain engineering,facilitating enhanced microbial production of a wide range of bioproducts.展开更多
Hansenula polymorpha DL-1 is a thermotolerant yeast capable of utilizing multiple renewable carbon sources,making it a promising microbial cell factory for sustainable manufacturing.However,advanced metabolic en-ginee...Hansenula polymorpha DL-1 is a thermotolerant yeast capable of utilizing multiple renewable carbon sources,making it a promising microbial cell factory for sustainable manufacturing.However,advanced metabolic en-gineering efforts have been constrained by its strong non-homologous end joining(NHEJ)mechanism and limited choice of suitable genetic tools.This study presents an optimized synthetic biology toolkit to address these limitations.A high-efficiency CRISPR-Cas9-based genome editing system was established,achieving an editing efficiency of 97.2%.To further enhance homologous recombination(HR),the NHEJ pathway was partially suppressed by knocking out KU80 and overexpressing HR-related genes from Saccharomyces cerevisiae.This increased HR rates to 88.9%.In addition,36 neutral sites were identified for stable single-copy gene integration without disrupting native gene expression cassettes.Finally,multi-copy integration tools were developed by targeting rDNA and Ty elements,leading to a~60-fold increase inβ-carotene production compared with single-copy integrants.Furthermore,squalene titers were increased from 0.1 mg/L in the wild-type strain to 187.2 mg/L through iterative multi-copy integration.These advances significantly expand the genetic tractability of H.polymorpha DL-1,underscoring its potential as a versatile platform for efficient and sustainable production of value-added compounds.展开更多
With the rapid popularity of cloud computing paradigm, disaster recovery using cloud resources becomes an attractive approach. This paper presents a practical multi-cloud based disaster recovery service model： DR- Cl...With the rapid popularity of cloud computing paradigm, disaster recovery using cloud resources becomes an attractive approach. This paper presents a practical multi-cloud based disaster recovery service model： DR- Cloud. With DR-Cloud, resources of multiple cloud service providers can be utilized cooperatively by the disaster recovery service provider. A simple and unified interface is exposed to the customers of DR-Cloud to adapt the heterogeneity of cloud service providers involved in the disaster recovery service, and the internal processes between clouds are invisible to the customers. DR-Cloud proposes multiple optimization scheduling strategies to balance the disaster recovery objectives, such as high data reliability, low backup cost, and short recovery time, which are also transparent to the customers. Different data scheduling strategies based on DR-Cloud are suitable for different kinds of data disaster recovery scenarios. Experimental results show that the DR-Cloud model can cooperate with cloud service providers with various parameters effectively, while its data scheduling strategies can achieve their optimization objectives efficiently and are widely applicable.展开更多
Humankind is facing unprecedented global environmental and social challenges in terms of food,water and energy security,resilience to natural hazards,etc.To address these challenges,international organizations have de...Humankind is facing unprecedented global environmental and social challenges in terms of food,water and energy security,resilience to natural hazards,etc.To address these challenges,international organizations have defined a list of policy actions to be achieved in a relatively short and medium-term timespan.The development and use of knowledge platforms is key in helping the decision-making process to take significant decisions(providing the best available knowledge)and avoid potentially negative impacts on society and the environment.Such knowledge platforms must build on the recent and next coming digital technologies that have transformed society–including the science and engineering sectors.Big Earth Data(BED)science aims to provide the methodologies and instruments to generate knowledge from numerous,complex,and diverse data sources.BED science requires the development of Geoscience Digital Ecosystems(GEDs),which bank on the combined use of fundamental technology units(i.e.big data,learning-driven artificial intelligence,and network-based computing platform)to enable the development of more detailed knowledge to observe and test planet Earth as a whole.This manuscript contributes to the BED science research domain,by presenting the Virtual Earth Cloud:a multi-cloud framework to support GDE implementation and generate knowledge on environmental and social sustainability.展开更多
Identification of genetic variants via high-throughput sequencing(HTS)technologies has been essential for both fundamental and clinical studies.However,to what extent the genome sequence composition affects variant ca...Identification of genetic variants via high-throughput sequencing(HTS)technologies has been essential for both fundamental and clinical studies.However,to what extent the genome sequence composition affects variant calling remains unclear.In this study,we identified 63,897 multi-copy sequences(MCSs)with a minimum length of 300 bp,each of which occurs at least twice in the human genome.The 151,749 genomic loci(multi-copy regions,or MCRs)harboring these MCSs account for 1.98% of the genome and are distributed unevenly across chromosomes.MCRs containing the same MCS tend to be located on the same chromosome.Gene Ontology(GO)analyses revealed that 3800 genes whose UTRs or exons overlap with MCRs are enriched for Golgirelated cellular component terms and various enzymatic activities in the GO biological function category.MCRs are also enriched for loci that are sensitive to neocarzinostatin-induced double-strand breaks.Moreover,genetic variants discovered by genome-wide association studies and recorded in dbSNP are significantly underrepresented in MCRs.Using simulated HTS datasets,we show that false variant discovery rates are significantly higher in MCRs than in other genomic regions.These results suggest that extra caution must be taken when identifying genetic variants in the MCRs via HTS technologies.展开更多
The Aspergillus oryzae expression system has been developed into a chassis for the production of heterologous lipases,attributed to its strong capabilities in protein production and secretion,robust post-translational...The Aspergillus oryzae expression system has been developed into a chassis for the production of heterologous lipases,attributed to its strong capabilities in protein production and secretion,robust post-translational modifications,and favourable safety profile.However,the system’s relatively low expression levels remain a challenge,hindering its ability to meet the increasing demands of large-scale production.Strain C19,screened by high-throughput methods combining droplet microfluidics and flow cytometry,was demonstrated to be a potential chassis cell based on fermentation kinetic analysis and transcriptome sequencing.By leveraging the endogenous α-amylase’s expression elements and integration sites,a combination of random and site-directed integration strategies was employed to enhance the expression of heterologous lipases in strain C19.As a result,lipase production in shake-flask fermentation reached a titer of 113.6 U/L.The study further demonstrated that the different α-amylase gene loci could serve as effective integration sites for the multi-copy expression of heterologous proteins because the lipase activity of the 3-amylase site integrated strain C19#1-ABC was 3.3 times higher than that of C19#1.Furthermore,fermentation results in a 5-L bioreactor indicated that optimization of fermentation processes and facilities had the potential to further increase heterologous protein expression levels.These findings offered valuable insights into the advancement of A.oryzae expression systems and the potential for scaling engineered strains for industrial applications.展开更多
Bacterial prodigiosins are red-colored secondary metabolites with multiple activities,such as anticancer,antimalarial and immunosuppressive,which hold great potential for medical applications.In this study,dramaticall...Bacterial prodigiosins are red-colored secondary metabolites with multiple activities,such as anticancer,antimalarial and immunosuppressive,which hold great potential for medical applications.In this study,dramatically enhanced prodigiosins(RED) production in Streptomyces coelicolor was achieved by combinatorial metabolic engineering,including inactivation of the repressor gene ohkA,deletion of the actinorhodin(ACT) and calcium-dependent antibiotic(CDA) biosynthetic gene clusters(BGCs) and multi-copy chromosomal integration of the RED BGC.The results showed that ohkA deletion led to a 1-fold increase of RED production over the wild-type strain M145.Then,the ACT and CDA BGCs were deleted successively based on the AohkA mutant(SBJ101).To achieve multi-copy RED BGC integration,artificial ΦC31 attB site(s) were inserted simultaneously at the position where the ACT and CDA BGCs were deleted.The resulting strains SBJ102(with a single deletion of the ACT BGC and insertion of one artificial attB site) and SBJ103(with the deletion of both BGCs and insertion of two artificial attB sites) produced 1.9-and 6-fold higher RED titers than M145,respectively.Finally,the entire RED BGC was introduced into mutants from SBJ101 to SBJ103,generating three mutants(from SBJ104 to SBJ106) with chromosomal integration of one to three copies of the RED BGC.The highest RED yield was from SBJ106,which produced a maximum level of 96.8 mg g^(-1) cell dry weight,showing a 12-fold increase relative to M145.Collectively,the metabolic engineering strategies employed in this study are very efficient for the construction of high prodigiosin-producing strains.展开更多
A novel set of five polymorphic di- or trinucleofide microsatellite loci suitable for population genetic study were developed from an enriched genomic library for the pest insect cotton bollworm, Helicoverpa armigera,...A novel set of five polymorphic di- or trinucleofide microsatellite loci suitable for population genetic study were developed from an enriched genomic library for the pest insect cotton bollworm, Helicoverpa armigera, and cross-amplifiability of these and other published loci was tested in a closely related species, the tobacco budworm, H.assulta. The expected heterozygosity at these loci ranges from 0.62 to 0.91 in the cotton bollworm. The observed allele numbers varies from 4 to 12 in the limited number of individuals tested. Although a large proportion of cloned microsatellite sequences are present in multi-copy in the cotton bollworm genome, the overwhelming majority of the finalized polymorphic diallelic loci are tri-nucleotide microsatellites - an unexpected outcome, which should facilitate subsequent genotyping analysis.展开更多
Taxadiene is an important precursor for the biosynthesis of highly effective anticancer drug paclitaxel,but its microbial biosynthesis yield is very low.In this study,we employed Yarrowia lipolytica as a microbial hos...Taxadiene is an important precursor for the biosynthesis of highly effective anticancer drug paclitaxel,but its microbial biosynthesis yield is very low.In this study,we employed Yarrowia lipolytica as a microbial host to produce taxadiene.First,a“push–pull”strategy was adopted to increase taxadiene production by 234%.Then taxadiene synthase was fused with five solubilizing tags respectively,leading a maximum increase of 62.3%in taxadiene production when fused with SUMO.Subsequently,a multi-copy iterative integration method was used to further increase taxadiene titer,achieving the maximum titer of 23.7 mg/L in shake flask culture after three rounds of integration.Finally,the taxadiene titer was increased to 101.4 mg/L by optimization of the fed-batch fermentation conditions.This is the first report of taxadiene biosynthesis accomplished in Y.lipolytica,serving as a good example for the sustainable production of taxadiene and other terpenoids in this oleaginous yeast.展开更多
EMSA and footprinting analyses have revealed that the-489—-414 bp and the-390—-345 bp(designated DC and PC respectively)upstream of the Aspergillus niger T21 glaA gene were bound by one protein factor in the A.niger...EMSA and footprinting analyses have revealed that the-489—-414 bp and the-390—-345 bp(designated DC and PC respectively)upstream of the Aspergillus niger T21 glaA gene were bound by one protein factor in the A.niger T21 whole cell extract.Both DC and PC contained CCAAT pentanucleotides.The functions of DC and PC in regulation of expression of glucoamylase(GLA)were studied.CCAAT pentanucleotides were replaced with CGTAA and the mutated DNA fragments DCm and PCm lost the binding activities of protein factors in vitro.In vivo when either DC or PC was mutated or the relative orientations between them were changed on the PglaA,the transcriptional activity of PglaA decreased to a basal level.Introduction of multi-copies of DC into the original site at the PglaA in A.niger T21 decreased the expression of endogenous GLA expression and the exogenous reporter E.coli uidA gene introduced under the PglaA promoter,while having no effect on the uidA gene under the control of PgpdA.EMSA re-vealed that the levels of the specific DNA-binding protein factors in the transformants maintained the same meaning that introduction of multi-copies of DC caused the titration effect.AnghapC gene was cloned from A.niger T21 cDNA and introduced into the DC multi-copied strains.The expression of AnghapC improved the expression of the endogenous GLA and the exogenous gene controlled by PglaA.These results showed that both the CCAAT pentanucleotides were necessary for DC and PC binding to the protein factors,and the simultaneous binding of DC and PC to the protein was necessary for promoting the transcriptional activity of PglaA.AngHapC was the specific positive trans-acting protein factor binding to DC.展开更多
Genomic integration of genes and pathway-sized DNA cassettes is often an indispensable way to construct robust and productive microbial cell factories.For some uncommon microbial hosts,such as Mycolicibacterium and My...Genomic integration of genes and pathway-sized DNA cassettes is often an indispensable way to construct robust and productive microbial cell factories.For some uncommon microbial hosts,such as Mycolicibacterium and Mycobacterium species,however,it is a challenge.Here,we present a multiplexed integrase-assisted site-specific recombination(miSSR)method to precisely and iteratively integrate genes/pathways with controllable copies in the chromosomes of Mycolicibacteria for the purpose of developing cell factories.First,a single-step multi-copy integration method was established in M.neoaurum by a combination application of mycobacteriophage L5 integrase and two-step allelic exchange strategy,the efficiencies of which were~100%for no more than three-copy integration events and decreased sharply to~20%for five-copy integration events.Second,the R4,Bxb1 andΦC31 bacteriophage Att/Int systems were selected to extend the available integration toolbox for multiplexed gene integration events.Third,a reconstructed mycolicibacterial Xer recombinases(Xer-cise)system was employed to recycle the selection marker of gene recombination to facilitate the iterative gene manipulation.As a proof of concept,the biosynthetic pathway of ergothioneine(EGT)in Mycolicibacterium neoaurum ATCC 25795 was achieved by remodeling its metabolic pathway with a miSSR system.With six copies of the biosynthetic gene clusters(BGCs)of EGT and pentose phosphate isomerase(PRT),the titer of EGT in the resulting strain in a 30 mL shake flask within 5 days was enhanced to 66 mg/L,which was 3.77 times of that in the wild strain.The improvements indicated that the miSSR system was an effective,flexible,and convenient tool to engineer the genomes of Mycolicibacteria as well as other strains in the Mycobacteriaceae due to their proximate evolutionary relationships.展开更多
DYF371 locus and single‑nucleotide polymorphisms(SNPs)defined as DYF371C or DYF371T were simultaneously examined for 142 Chinese unrelated male individuals,including 90 Han population and 52 minorities.In total,37 SNP...DYF371 locus and single‑nucleotide polymorphisms(SNPs)defined as DYF371C or DYF371T were simultaneously examined for 142 Chinese unrelated male individuals,including 90 Han population and 52 minorities.In total,37 SNP-short tandem repeat haplotypes were detected.Nine of these 37 haplotypes were unique(24.32%).The gene diversity and discrimination capacity values are 0.8321 and 0.2606,respectively.Furthermore,only five males(5.55%)in the Han samples were determined that they had one copy of allele with SNP T-type and three copies of alleles with SNP C-types,whereas 14 individuals(26.92%)were observed in minorities’samples.The genotype proportion comprising three distinguishing copies of the allele with SNP C-types in Han sample was greatly lower than that in the sample of minorities.Similar results were shown for allele 11C and 10C.Therefore,the alleles of DYF371 with SNP C-type have the potential to differentiate the Han and non-Han Chinese populations.展开更多
基金supported in part by the National Natural Science Foundation of China(61673123,61603100)in part by the Natural Science Foundation of Guangdong Province,China(2020A151501482)。
文摘The rise of multi-cloud systems has been spurred.For safety-critical missions,it is important to guarantee their security and reliability.To address trust constraints in a heterogeneous multi-cloud environment,this work proposes a novel scheduling method called matching and multi-round allocation(MMA)to optimize the makespan and total cost for all submitted tasks subject to security and reliability constraints.The method is divided into two phases for task scheduling.The first phase is to find the best matching candidate resources for the tasks to meet their preferential demands including performance,security,and reliability in a multi-cloud environment;the second one iteratively performs multiple rounds of re-allocating to optimize tasks execution time and cost by minimizing the variance of the estimated completion time.The proposed algorithm,the modified cuckoo search(MCS),hybrid chaotic particle search(HCPS),modified artificial bee colony(MABC),max-min,and min-min algorithms are implemented in CloudSim to create simulations.The simulations and experimental results show that our proposed method achieves shorter makespan,lower cost,higher resource utilization,and better trade-off between time and economic cost.It is more stable and efficient.
文摘Cloud computingmakes dynamic resource provisioning more accessible.Monitoring a functioning service is crucial,and changes are made when particular criteria are surpassed.This research explores the decentralized multi-cloud environment for allocating resources and ensuring the Quality of Service(QoS),estimating the required resources,and modifying allotted resources depending on workload and parallelism due to resources.Resource allocation is a complex challenge due to the versatile service providers and resource providers.The engagement of different service and resource providers needs a cooperation strategy for a sustainable quality of service.The objective of a coherent and rational resource allocation is to attain the quality of service.It also includes identifying critical parameters to develop a resource allocation mechanism.A framework is proposed based on the specified parameters to formulate a resource allocation process in a decentralized multi-cloud environment.The three main parameters of the proposed framework are data accessibility,optimization,and collaboration.Using an optimization technique,these three segments are further divided into subsets for resource allocation and long-term service quality.The CloudSim simulator has been used to validate the suggested framework.Several experiments have been conducted to find the best configurations suited for enhancing collaboration and resource allocation to achieve sustained QoS.The results support the suggested structure for a decentralized multi-cloud environment and the parameters that have been determined.
基金supported by Science and Technology Development Foundation of the Central Guiding Local under Grant No.YDZJSX2021A038the National Natural Science Foundation of China under Grant No.61806138China University Industry-University-Research Collaborative Innovation Fund (Future Network Innovation Research and Application Project)under Grant No.2021FNA04014.
文摘Cloud computing technology is favored by users because of its strong computing power and convenient services.At the same time,scheduling performance has an extremely efficient impact on promoting carbon neutrality.Currently,scheduling research in the multi-cloud environment aims to address the challenges brought by business demands to cloud data centers during peak hours.Therefore,the scheduling problem has promising application prospects under themulti-cloud environment.This paper points out that the currently studied scheduling problems in the multi-cloud environment mainly include independent task scheduling and workflow task scheduling based on the dependencies between tasks.This paper reviews the concepts,types,objectives,advantages,challenges,and research status of task scheduling in the multi-cloud environment.Task scheduling strategies proposed in the existing related references are analyzed,discussed,and summarized,including research motivation,optimization algorithm,and related objectives.Finally,the research status of the two kinds of task scheduling is compared,and several future important research directions of multi-cloud task scheduling are proposed.
基金supported by Putra Grant,University PutraMalaysia,under Grant 95960000 and in part by the Ministry of Education(MOE)Malaysia.
文摘One of the fundamental problems associated with scheduling workflows on virtual machines in a multi-cloud environment is how to find a near-optimum permutation.The workflow scheduling involves assigning independent computational jobs with conflicting objectives to a set of virtual machines.Most optimization methods for solving non-deterministic polynomial-time hardness(NP-hard)problems deploy multi-objective algorithms.As such,Pareto dominance is one of the most efficient criteria for determining the best solutions within the Pareto front.However,the main drawback of this method is that it requires a reasonably long time to provide an optimum solution.In this paper,a new multi-objective minimum weight algorithm is used to derive the Pareto front.The conflicting objectives considered are reliability,cost,resource utilization,risk probability and makespan.Because multi-objective algorithms select a number of permutations with an optimal trade-off between conflicting objectives,we propose a new decisionmaking approach named the minimum weight optimization(MWO).MWO produces alternative weight to determine the inertia weight by using an adaptive strategy to provide an appropriate alternative for all optimal solutions.This way,consumers’needs and service providers’interests are taken into account.Using standard scientific workflows with conflicting objectives,we compare our proposed multi-objective scheduling algorithm using minimum weigh optimization(MOS-MWO)with multi-objective scheduling algorithm(MOS).Results show that MOS-MWO outperforms MOS in term of QoS satisfaction rate.
基金This work was supported by the Ministry of Education and China Mobile Research Fund Project(MCM20200102)the 173 Project(No.2019-JCJQ-ZD-342-00)+2 种基金the National Natural Science Foundation of China(No.U19A2081)the Fundamental Research Funds for the Central Universities(No.2023SCU12129)the Science and Engineering Connotation Development Project of Sichuan University(No.2020SCUNG129).
文摘Due to the need for massive device connectivity,low communication latency,and various customizations in 6G architecture,a distributed cloud deployment approach will be more relevant to the space-air-ground-sea integrated network scenario.However,the openness and heterogeneity of the 6G network cause the problems of network security.To improve the trustworthiness of 6G networks,we propose a trusted computing-based approach for establishing trust relationships inmulti-cloud scenarios.The proposed method shows the relationship of trust based on dual-level verification.It separates the trustworthy states of multiple complex cloud units in 6G architecture into the state within and between cloud units.Firstly,SM3 algorithm establishes the chain of trust for the system’s trusted boot phase.Then,the remote attestation server(RAS)of distributed cloud units verifies the physical servers.Meanwhile,the physical servers use a ring approach to verify the cloud servers.Eventually,the centralized RAS takes one-time authentication to the critical evidence information of distributed cloud unit servers.Simultaneously,the centralized RAS also verifies the evidence of distributed RAS.We establish our proposed approach in a natural OpenStack-based cloud environment.The simulation results show that the proposed method achieves higher security with less than a 1%system performance loss.
基金This study is supported by the National Natural Science Foundation of China(61370069), the National High Technology Research and Development Program("863"Program) of China (2012AA012600), the Cosponsored Project of Beijing Committee of Education,the Fundamental Research Funds for the Central Universities (BUPT2011RCZJ16) and China Information Security Special Fund (NDRC).
文摘The benefits of cloud storage come along with challenges and open issues about availability of services, vendor lock-in and data security, etc. One solution to mitigate the problems is the multi-cloud storage, where the selection of service providers is a key point. In this paper, an algorithm that can select optimal provider subset for data placement among a set of providers in multicloud storage architecture based on IDA is proposed, designed to achieve good tradeoff among storage cost, algorithm cost, vendor lock-in, transmission performance and data availability. Experiments demonstrate that it is efficient and accurate to find optimal solutions in reasonable amount of time, using parameters taken from real cloud providers.
文摘The purpose of this paper is to provide a better knowledge of the cloud computing as well as to suggest relevant research paths in this growing field. Also, we will go through the future benefits of cloud computing and the upcoming possible challenges we will have. Intext Cloud, performance, cloud computing, architecture, scale-up, and big data are all terms used in this context. Cloud computing offers a wide range of architectural configurations, including the number of processors, memory, and nodes. Cloud computing has already changed the way we store, process, and access data, and it is expected to continue to have a significant impact on the future of information technology. Cloud computing enables organizations to scale their IT resources up or down quickly and easily, without the need for costly hardware upgrades. This can help organizations to respond more quickly to changing business needs and market conditions. By moving IT resources to the cloud, organizations can reduce their IT infrastructure costs and improve their operational efficiency. Cloud computing also allows organizations to pay only for the resources they use, rather than investing in expensive hardware and software licenses. Cloud providers invest heavily in security and compliance measures, which can help to protect organizations from cyber threats and ensure regulatory compliance. Cloud computing provides a scalable platform for AI and machine learning applications, enabling organizations to build and deploy these technologies more easily and cost-effectively. A task, an application, and its input can take up to 20 times longer or cost 10 times more than optimal. Cloud products’ ready adaptability has resulted in a paradigm change. Previously, an application was optimized for a specific cluster;however, in the cloud, the architectural configuration is tuned for the workload. The evolution of cloud computing from the era of mainframes and dumb terminals has been significant, but there are still many advancements to come. As we look towards the future, IT leaders and the companies they serve will face increasingly complex challenges in order to stay competitive in a constantly evolving cloud computing landscape. Additionally, it will be crucial to remain compliant with existing regulations as well as new regulations that may emerge in the future. It is safe to say that the next decade of cloud computing will be just as dramatic as the last where many internet services are becoming cloud-based, and huge enterprises will struggle to fund physical infrastructure. Cloud computing is significantly used in business innovation and because of its agility and adaptability, cloud technology enables new ways of working, operating, and running a business. The service enables users to access files and applications stored in the cloud from anywhere, removing the requirement for users to be always physically close to actual hardware. Cloud computing makes the connection available from anywhere because they are kept on a network of hosted computers that carry data over the internet. Cloud computing has shown to be advantageous to both consumers and corporations. To be more specific, the cloud has altered our way of life. Overall, cloud computing is likely to continue to play a significant role in the future of IT, enabling organizations to become more agile, efficient, and innovative in the face of rapid technological change. This is likely to drive further innovation in AI and machine learning in the coming years.
基金support from Open Funding Project of Guangdong Provincial Key Laboratory of Silviculture,Protection and Utilization(SPU2023-07)Research Project of Applied Basic Research Program of Department of Science and Technology of Liaoning Province(2022JH2/101300137)Dalian University Interdisciplinary Project(DLUXK-2-23-QN-006)。
文摘High-copy integration of key genes offers a promising strategy for efficient biosynthesis of valuable natural products in Saccharomyces cerevisiae.However,traditional multi-copy gene integration methods meet challenges including low efficiency and labor-intensive screening processes.In this study,we developed the IMIGE(Iterative Multi-copy Integration by Gene Editing)system,a CRISPR/Cas9-based approach that exploits bothδand rDNA repetitive sequences for simultaneous multi-copy integrations in S.cerevisiae.This system combines the mixture of Cas9-sgRNA expression vectors with a split-marker strategy for efficient donor DNA assembly in vivo and enables rapid,iterative screening through growth-related phenotypes.When applied to the biosynthesis of ergothioneine and cordycepin,the IMIGE system achieved significant yield improvements,with titers of 105.31±1.53 mg/L and 62.01±2.4 mg/L,respectively,within just two screening cycles(5.5-6 days in total).These yields represent increases of 407.39%and 222.13%,respectively,compared to the strains with episomal expression.By streamlining the integration process,utilizing growth-based selection,and minimizing screening demands in both equipment and labor,the IMIGE system could provide an efficient and scalable platform for high-throughput strain engineering,facilitating enhanced microbial production of a wide range of bioproducts.
基金supported by the National Key Research and Development Program of China(2023YFF1103700)the Jiangsu Funding Program for Excellent Postdoctoral Talent(2024ZB296)the Post-doctoral Fellowship Program of CPSF(under grant number GZC20240609).
文摘Hansenula polymorpha DL-1 is a thermotolerant yeast capable of utilizing multiple renewable carbon sources,making it a promising microbial cell factory for sustainable manufacturing.However,advanced metabolic en-gineering efforts have been constrained by its strong non-homologous end joining(NHEJ)mechanism and limited choice of suitable genetic tools.This study presents an optimized synthetic biology toolkit to address these limitations.A high-efficiency CRISPR-Cas9-based genome editing system was established,achieving an editing efficiency of 97.2%.To further enhance homologous recombination(HR),the NHEJ pathway was partially suppressed by knocking out KU80 and overexpressing HR-related genes from Saccharomyces cerevisiae.This increased HR rates to 88.9%.In addition,36 neutral sites were identified for stable single-copy gene integration without disrupting native gene expression cassettes.Finally,multi-copy integration tools were developed by targeting rDNA and Ty elements,leading to a~60-fold increase inβ-carotene production compared with single-copy integrants.Furthermore,squalene titers were increased from 0.1 mg/L in the wild-type strain to 187.2 mg/L through iterative multi-copy integration.These advances significantly expand the genetic tractability of H.polymorpha DL-1,underscoring its potential as a versatile platform for efficient and sustainable production of value-added compounds.
基金supported by the National High-Tech Research and Development(863)Program of China(No.2012AA012609)
文摘With the rapid popularity of cloud computing paradigm, disaster recovery using cloud resources becomes an attractive approach. This paper presents a practical multi-cloud based disaster recovery service model： DR- Cloud. With DR-Cloud, resources of multiple cloud service providers can be utilized cooperatively by the disaster recovery service provider. A simple and unified interface is exposed to the customers of DR-Cloud to adapt the heterogeneity of cloud service providers involved in the disaster recovery service, and the internal processes between clouds are invisible to the customers. DR-Cloud proposes multiple optimization scheduling strategies to balance the disaster recovery objectives, such as high data reliability, low backup cost, and short recovery time, which are also transparent to the customers. Different data scheduling strategies based on DR-Cloud are suitable for different kinds of data disaster recovery scenarios. Experimental results show that the DR-Cloud model can cooperate with cloud service providers with various parameters effectively, while its data scheduling strategies can achieve their optimization objectives efficiently and are widely applicable.
基金The research leading to these results benefited from funding by the European Union's Horizon 2020 Framework Programme research and innovation programme[under grant agreements:n.689443(ERA-PLANET),n.777536(EOSC-hub),n.776136(EDGE),n.34538(EO Value),n.101039118(GPP)]by the European Space Agency[under ESA Contracts:n.4000123005/18/IT/CGD(DAB4EDGE)and n.4000138128/22/I/AG(DAB4GPP)]European Commission CNECT(grant n.35713).
文摘Humankind is facing unprecedented global environmental and social challenges in terms of food,water and energy security,resilience to natural hazards,etc.To address these challenges,international organizations have defined a list of policy actions to be achieved in a relatively short and medium-term timespan.The development and use of knowledge platforms is key in helping the decision-making process to take significant decisions(providing the best available knowledge)and avoid potentially negative impacts on society and the environment.Such knowledge platforms must build on the recent and next coming digital technologies that have transformed society–including the science and engineering sectors.Big Earth Data(BED)science aims to provide the methodologies and instruments to generate knowledge from numerous,complex,and diverse data sources.BED science requires the development of Geoscience Digital Ecosystems(GEDs),which bank on the combined use of fundamental technology units(i.e.big data,learning-driven artificial intelligence,and network-based computing platform)to enable the development of more detailed knowledge to observe and test planet Earth as a whole.This manuscript contributes to the BED science research domain,by presenting the Virtual Earth Cloud:a multi-cloud framework to support GDE implementation and generate knowledge on environmental and social sustainability.
基金supported by the National Natural Science Foundation of China(NSFC,Grant No.31771479)Science Fund for Creative Research Groups of the NSFC(Grant No.81521003)+5 种基金Projects of International Cooperation and Exchanges of NSFC(Grant No.61661146004)Municipal Planning Projects of Scientific Technology of Guangdong(Grant No.201804020083)the Science and Technology Program of Guangzhou(Grant No.201400000004)the Natural Science Foundation of Guangdong(Grant No.2015B050501006)the Team Program of Natural Science Foundation of Guangdong(Grant No.2014A030312002)the 1000 Talents Program of China。
文摘Identification of genetic variants via high-throughput sequencing(HTS)technologies has been essential for both fundamental and clinical studies.However,to what extent the genome sequence composition affects variant calling remains unclear.In this study,we identified 63,897 multi-copy sequences(MCSs)with a minimum length of 300 bp,each of which occurs at least twice in the human genome.The 151,749 genomic loci(multi-copy regions,or MCRs)harboring these MCSs account for 1.98% of the genome and are distributed unevenly across chromosomes.MCRs containing the same MCS tend to be located on the same chromosome.Gene Ontology(GO)analyses revealed that 3800 genes whose UTRs or exons overlap with MCRs are enriched for Golgirelated cellular component terms and various enzymatic activities in the GO biological function category.MCRs are also enriched for loci that are sensitive to neocarzinostatin-induced double-strand breaks.Moreover,genetic variants discovered by genome-wide association studies and recorded in dbSNP are significantly underrepresented in MCRs.Using simulated HTS datasets,we show that false variant discovery rates are significantly higher in MCRs than in other genomic regions.These results suggest that extra caution must be taken when identifying genetic variants in the MCRs via HTS technologies.
基金supported by the National Key Research and Development Program of China(2021YFC2104000)the National Natural Science Foundation of China(32172153)the Natural Science Foundation of Jiangsu Province(BK20202002).
文摘The Aspergillus oryzae expression system has been developed into a chassis for the production of heterologous lipases,attributed to its strong capabilities in protein production and secretion,robust post-translational modifications,and favourable safety profile.However,the system’s relatively low expression levels remain a challenge,hindering its ability to meet the increasing demands of large-scale production.Strain C19,screened by high-throughput methods combining droplet microfluidics and flow cytometry,was demonstrated to be a potential chassis cell based on fermentation kinetic analysis and transcriptome sequencing.By leveraging the endogenous α-amylase’s expression elements and integration sites,a combination of random and site-directed integration strategies was employed to enhance the expression of heterologous lipases in strain C19.As a result,lipase production in shake-flask fermentation reached a titer of 113.6 U/L.The study further demonstrated that the different α-amylase gene loci could serve as effective integration sites for the multi-copy expression of heterologous proteins because the lipase activity of the 3-amylase site integrated strain C19#1-ABC was 3.3 times higher than that of C19#1.Furthermore,fermentation results in a 5-L bioreactor indicated that optimization of fermentation processes and facilities had the potential to further increase heterologous protein expression levels.These findings offered valuable insights into the advancement of A.oryzae expression systems and the potential for scaling engineered strains for industrial applications.
基金supported by the National Natural Science Foundation of China(31430004,31421061,31630003,31370081 and 31570072)the Science and Technology Commission of Shanghai Municipality(16490712100)
文摘Bacterial prodigiosins are red-colored secondary metabolites with multiple activities,such as anticancer,antimalarial and immunosuppressive,which hold great potential for medical applications.In this study,dramatically enhanced prodigiosins(RED) production in Streptomyces coelicolor was achieved by combinatorial metabolic engineering,including inactivation of the repressor gene ohkA,deletion of the actinorhodin(ACT) and calcium-dependent antibiotic(CDA) biosynthetic gene clusters(BGCs) and multi-copy chromosomal integration of the RED BGC.The results showed that ohkA deletion led to a 1-fold increase of RED production over the wild-type strain M145.Then,the ACT and CDA BGCs were deleted successively based on the AohkA mutant(SBJ101).To achieve multi-copy RED BGC integration,artificial ΦC31 attB site(s) were inserted simultaneously at the position where the ACT and CDA BGCs were deleted.The resulting strains SBJ102(with a single deletion of the ACT BGC and insertion of one artificial attB site) and SBJ103(with the deletion of both BGCs and insertion of two artificial attB sites) produced 1.9-and 6-fold higher RED titers than M145,respectively.Finally,the entire RED BGC was introduced into mutants from SBJ101 to SBJ103,generating three mutants(from SBJ104 to SBJ106) with chromosomal integration of one to three copies of the RED BGC.The highest RED yield was from SBJ106,which produced a maximum level of 96.8 mg g^(-1) cell dry weight,showing a 12-fold increase relative to M145.Collectively,the metabolic engineering strategies employed in this study are very efficient for the construction of high prodigiosin-producing strains.
文摘A novel set of five polymorphic di- or trinucleofide microsatellite loci suitable for population genetic study were developed from an enriched genomic library for the pest insect cotton bollworm, Helicoverpa armigera, and cross-amplifiability of these and other published loci was tested in a closely related species, the tobacco budworm, H.assulta. The expected heterozygosity at these loci ranges from 0.62 to 0.91 in the cotton bollworm. The observed allele numbers varies from 4 to 12 in the limited number of individuals tested. Although a large proportion of cloned microsatellite sequences are present in multi-copy in the cotton bollworm genome, the overwhelming majority of the finalized polymorphic diallelic loci are tri-nucleotide microsatellites - an unexpected outcome, which should facilitate subsequent genotyping analysis.
基金supported by the National Key Research and Development Program of China(2019YFA0905000)the National Natural Science Foundation of China(21871085 and 31971380)the Fundamental Research Funds for the Central Universities(222201714026).
文摘Taxadiene is an important precursor for the biosynthesis of highly effective anticancer drug paclitaxel,but its microbial biosynthesis yield is very low.In this study,we employed Yarrowia lipolytica as a microbial host to produce taxadiene.First,a“push–pull”strategy was adopted to increase taxadiene production by 234%.Then taxadiene synthase was fused with five solubilizing tags respectively,leading a maximum increase of 62.3%in taxadiene production when fused with SUMO.Subsequently,a multi-copy iterative integration method was used to further increase taxadiene titer,achieving the maximum titer of 23.7 mg/L in shake flask culture after three rounds of integration.Finally,the taxadiene titer was increased to 101.4 mg/L by optimization of the fed-batch fermentation conditions.This is the first report of taxadiene biosynthesis accomplished in Y.lipolytica,serving as a good example for the sustainable production of taxadiene and other terpenoids in this oleaginous yeast.
基金supported by the National Natural Science Foundation of China(Grant No.30170014).
文摘EMSA and footprinting analyses have revealed that the-489—-414 bp and the-390—-345 bp(designated DC and PC respectively)upstream of the Aspergillus niger T21 glaA gene were bound by one protein factor in the A.niger T21 whole cell extract.Both DC and PC contained CCAAT pentanucleotides.The functions of DC and PC in regulation of expression of glucoamylase(GLA)were studied.CCAAT pentanucleotides were replaced with CGTAA and the mutated DNA fragments DCm and PCm lost the binding activities of protein factors in vitro.In vivo when either DC or PC was mutated or the relative orientations between them were changed on the PglaA,the transcriptional activity of PglaA decreased to a basal level.Introduction of multi-copies of DC into the original site at the PglaA in A.niger T21 decreased the expression of endogenous GLA expression and the exogenous reporter E.coli uidA gene introduced under the PglaA promoter,while having no effect on the uidA gene under the control of PgpdA.EMSA re-vealed that the levels of the specific DNA-binding protein factors in the transformants maintained the same meaning that introduction of multi-copies of DC caused the titration effect.AnghapC gene was cloned from A.niger T21 cDNA and introduced into the DC multi-copied strains.The expression of AnghapC improved the expression of the endogenous GLA and the exogenous gene controlled by PglaA.These results showed that both the CCAAT pentanucleotides were necessary for DC and PC binding to the protein factors,and the simultaneous binding of DC and PC to the protein was necessary for promoting the transcriptional activity of PglaA.AngHapC was the specific positive trans-acting protein factor binding to DC.
基金supported by the National Natural Science Foundation of China(No.21776075)the Natural Science Foundation of Shanghai(No.20ZR1415100)the National Key Research and Development Program of China(No.SQ2020YFC210061).
文摘Genomic integration of genes and pathway-sized DNA cassettes is often an indispensable way to construct robust and productive microbial cell factories.For some uncommon microbial hosts,such as Mycolicibacterium and Mycobacterium species,however,it is a challenge.Here,we present a multiplexed integrase-assisted site-specific recombination(miSSR)method to precisely and iteratively integrate genes/pathways with controllable copies in the chromosomes of Mycolicibacteria for the purpose of developing cell factories.First,a single-step multi-copy integration method was established in M.neoaurum by a combination application of mycobacteriophage L5 integrase and two-step allelic exchange strategy,the efficiencies of which were~100%for no more than three-copy integration events and decreased sharply to~20%for five-copy integration events.Second,the R4,Bxb1 andΦC31 bacteriophage Att/Int systems were selected to extend the available integration toolbox for multiplexed gene integration events.Third,a reconstructed mycolicibacterial Xer recombinases(Xer-cise)system was employed to recycle the selection marker of gene recombination to facilitate the iterative gene manipulation.As a proof of concept,the biosynthetic pathway of ergothioneine(EGT)in Mycolicibacterium neoaurum ATCC 25795 was achieved by remodeling its metabolic pathway with a miSSR system.With six copies of the biosynthetic gene clusters(BGCs)of EGT and pentose phosphate isomerase(PRT),the titer of EGT in the resulting strain in a 30 mL shake flask within 5 days was enhanced to 66 mg/L,which was 3.77 times of that in the wild strain.The improvements indicated that the miSSR system was an effective,flexible,and convenient tool to engineer the genomes of Mycolicibacteria as well as other strains in the Mycobacteriaceae due to their proximate evolutionary relationships.
文摘DYF371 locus and single‑nucleotide polymorphisms(SNPs)defined as DYF371C or DYF371T were simultaneously examined for 142 Chinese unrelated male individuals,including 90 Han population and 52 minorities.In total,37 SNP-short tandem repeat haplotypes were detected.Nine of these 37 haplotypes were unique(24.32%).The gene diversity and discrimination capacity values are 0.8321 and 0.2606,respectively.Furthermore,only five males(5.55%)in the Han samples were determined that they had one copy of allele with SNP T-type and three copies of alleles with SNP C-types,whereas 14 individuals(26.92%)were observed in minorities’samples.The genotype proportion comprising three distinguishing copies of the allele with SNP C-types in Han sample was greatly lower than that in the sample of minorities.Similar results were shown for allele 11C and 10C.Therefore,the alleles of DYF371 with SNP C-type have the potential to differentiate the Han and non-Han Chinese populations.
