Streptococcus equi subsp.zooepidemicus(SEZ)is an important zoonotic agent.Here,a virulence-attenuated strain M35246 derived from natural variation of wild-type SEZ ATCC35246 was found.M35246 showed a deletion of 25con...Streptococcus equi subsp.zooepidemicus(SEZ)is an important zoonotic agent.Here,a virulence-attenuated strain M35246 derived from natural variation of wild-type SEZ ATCC35246 was found.M35246 showed a deletion of 25contiguous genes as well as a loss-of-function mutation in covS.Subsequently,a 25-gene-deleted strain(ΔPI),a covS-mutant strain(Mcov S),and relevant complementary strains were constructed and investigated.M35246 and Mcov S were significantly less encapsulated and exhibited poorer anti-phagocytic capacity compared to wild-type SEZ.McovS was significantly more sensitive toβ-lactams,aminoglycosides,macrolides,and lincosamides than wild-type SEZ.M35246,McovS,andΔPI exhibited an increase in median lethal dose(LD_(50))in mice by 10~5,10~5,and 5 times when compared to wild-type SEZ,respectively.Neither M35246 nor McovS were isolated from mice 48 h after being challenged with approximately 2000 times the LD_(50)of wild-type SEZ.Transcriptome analysis showed that 668 significantly differentially expressed genes existed between McovS and wild-type SEZ.Numerous virulence factor-encoding genes and anabolicrelated genes in McovS that were involved in anti-phagocytosis,capsule formation,pathogenicity,and antibiotic resistance were downregulated significantly relative to the wild-type strain.This study revealed that the CovS plays a vital role in the establishment of SEZ virulence.展开更多
1)Bifidobacterium longum subsp.iuvenis(Modesto et al.IJSEM.2023,73:6013;Type strain:NCC 5000 T=CCOS 2034 T=LMG 32752^(T))Etymology:iu’ve.nis.L.gen.masc./fem.n.iuvenis,of child,because the type strain was isolated fro...1)Bifidobacterium longum subsp.iuvenis(Modesto et al.IJSEM.2023,73:6013;Type strain:NCC 5000 T=CCOS 2034 T=LMG 32752^(T))Etymology:iu’ve.nis.L.gen.masc./fem.n.iuvenis,of child,because the type strain was isolated from a 2 year old Bangladeshi child.长双歧杆菌幼儿亚种.展开更多
Bacterial soft rot(BSR)caused by Pectobacterium carotovorum subsp.brasiliense(Pcb)is a serious bacterial disease which negatively impact yield and quality in cucumber.However,the genetic mechanism of BSR resistance in...Bacterial soft rot(BSR)caused by Pectobacterium carotovorum subsp.brasiliense(Pcb)is a serious bacterial disease which negatively impact yield and quality in cucumber.However,the genetic mechanism of BSR resistance in cucumber has not been reported.Here,we investigated the BSR resistance of 119 cucumber core germplasm worldwide at the seedling stage and identified 26 accessions highly resistant to BSR.A total of 1642740 single-nucleotide polymorphisms(SNPs)were used to conduct GWAS,and five loci associated with BSR resistance were detected on four chromosomes:gBSR2.1,gBSR2.2,gBSR3.1,gBSR4.1 and gBSR5.1.Based on haplotype analysis,sequence polymorphisms,functional annotation and qRT-PCR analysis,six candidate genes were identified within the five loci.CsaV3_2G014450,CsaV3_2G014490,CsaV3_2G016000,CsaV3_3G000850,CsaV3_4G033150,and CsaV3_5G000390 each had nonsynonymous SNPs,and were significantly up-regulated in the resistant genotypes after inoculation.And CsaV3_5G000390 in the susceptible genotype was significantly up-regulated after inoculation.The identification of these candidate genes lays a foundation for understanding the genetic mechanism of BSR resistance in cucumber.Generally,our study mined genes associated with BSR resistance in cucumber seedlings and will assist the breeding of BSR-resistant cucumber cultivars.展开更多
Background:The maturation of the immune system is critical during early life,as it involves the differentiation,maturation,and establishment of immune tolerance of immune cells.This process is influenced not only by g...Background:The maturation of the immune system is critical during early life,as it involves the differentiation,maturation,and establishment of immune tolerance of immune cells.This process is influenced not only by genetic factors but also by en-vironmental factors,particularly the symbiotic microbiota.Bifidobacterium animalis subsp.lactis(BB-12),originally found in dairy products,is widely used in infant for-mula and dietary supplements.However,its role and mechanisms in immune develop-ment during early life remain unclear.Methods:Using GF mice as the experimental model,B.animalis subsp.lactis BB-12 was administered via gavage during early life.In the juvenile stage,changes in T-cell subsets in the spleen,thymus,and gut intraepithelial lymphocytes(IEL)were assessed using spectral flow cytometry.Additionally,targeted metabolomics analysis of trypto-phan metabolism and short-chain fatty acid pathways in colonic tissue was conducted to explore how B.animalis subsp.lactis BB-12 influences the immune system through gut microbiota metabolism.Results:BB-12 effectively modulates the gut immune microenvironment,leading to beneficial changes in T-cell subsets in key immune tissues such as the spleen,thymus,and gut IELs.Metabolomics analysis further supports these findings by showing that BB-12 intervention greatly increased the production of tryptophan derivatives and acetic acid in the colon of GF mice.Conclusion:The findings provide theoretical evidence for the role of B.animalis subsp.lactis in immune system development and support its application in dietary supple-ments,suggesting potential as a component for infant immune health and in prevent-ing immune-related diseases.展开更多
Bifidobacterium longum subsp.infantis and Bifidobacterium adolescentis play important roles in the guts of infants and adolescents,respectively.In this study,using a neonatal rat model,we compared the protective effec...Bifidobacterium longum subsp.infantis and Bifidobacterium adolescentis play important roles in the guts of infants and adolescents,respectively.In this study,using a neonatal rat model,we compared the protective effects of these 2 bifidobacterial species against Salmonella infection.The results demonstrated that B.longum subsp.infantis was more effective than B.adolescentis in alleviating the severity of infection in newborn rats exposed to Salmonella enterica serovar Typhimurium strain SL1344.B.longum subsp.infantis attenuated intestinal inflammation and mucosal damage induced by Salmonella infection,as well as protecting intestinal nerves and intestinal barrier function through TLR4/My D88 signalling.B.longum subsp.infantis also displayed the potential to modulate gut metabolites by promoting the biosynthesis of unsaturated fatty acids(arachidonic acid,eicosapentaenoic acid andα-linolenic acid)and purine metabolism(guanine,adenine,inosine and adenosine),thereby regulating metabolic disturbances.Additionally,the benefits of B.longum subsp.infantis were also observed in the liver,spleen and brain,improving nerve reflexes and suppressing hepatosplenomegaly.Overall,these findings provide novel insights into the prevention and treatment of gutrelated diseases in newborns,highlighting the potentially significant role of B.longum subsp.infantis in clinical applications.展开更多
Accumulating evidence suggests that probiotics affect the microbial-gut-brain axis in a way that can prevent and treat Alzheimer's disease(AD).However,the mechanism underlying the therapeutic effects still needs t...Accumulating evidence suggests that probiotics affect the microbial-gut-brain axis in a way that can prevent and treat Alzheimer's disease(AD).However,the mechanism underlying the therapeutic effects still needs to be further investigated.This study aimed to examine the alleviating effect of Lacticaseibacillus paracasei L9 and Bifidobacterium animalis subsp.lactis A6 and possible mechanism in mice with AD.In this study,the administration of probiotics L9 and A6 effectively improved memory and learning functions in AD mice.The hippocampal cells of mice were partly recovered in morphology and rearranged more neatly after probiotics intervention.Meanwhile,L9 and A6 exhibited inhibitory effects on the phosphorylation of Tau and the deposition of Aβ,which were mediated via GSK-3βand PP2A kinases.Meanwhile,by metagenomic sequencing,we found interventions with L9 and A6 altered the intestinal microbiome's taxonomic composition,reduced the abundance of pathogenic Desulfovibrio genera,and increased beneficial Clostridium and Paramuribaculum genera abundance.The fatty acids metabolism and biosynthesis of gut microbiome were also enhanced.Serum untargeted metabolomics also showed noticeable alternation in lipidrelated metabolites,which may alleviate the pathogenesis of AD.These results revealed a mitigating role for probiotic L9 and A6 in AD prevention and offer new insights into AD prevention via gut-brain connection.展开更多
Bifidobacterium longum subsp.infantis is a commensal bacterium that predominates in the infant gut,playing a critical role in both preventing foreign infections and facilitating immune development.This study aimed to ...Bifidobacterium longum subsp.infantis is a commensal bacterium that predominates in the infant gut,playing a critical role in both preventing foreign infections and facilitating immune development.This study aimed to explore the effects of B.longum subsp.infantis supplementation on interferon-beta(IFN-β)secretion and intestinal barrier improvement in growing mice.Female and male mice were orally administered either saline or B.longum subsp.infantis CCFM1269 or I5TI(1×10^(9) CFU/mice per day,n=8)from 1-week-age until 3-,4-,and 5-week-age.RNA sequencing analysis revealed that CCFM1269 exhibited potential antiviral capacity through increasing 2'-5'oligoadenylate synthetase(OAS).Additionally,CCFM1269 supplementation significantly increased colonic IFN-β levels which combined with OAS in 3-week-old female and male mice by activating the TLR4-TRIF-dependent signaling pathway.However,this effect was not observed in 4-and 5-week-old mice.Furthermore,both CCFM1269 were found to modulate the gut microbiota composition and enhance the intestinal barrier function in 3-,4-,and 5-week-old mice.In summary,the results of this study suggested that B.longum subsp.infantis CCFM1269 promoting intestinal barrier and releasing IFN-β in growing mice was in a strain-specific and time-dependent manner.展开更多
【目的】分离鉴定江苏省扬州市养殖场异育银鲫患病病原。【方法】采用常规的理化特性和分子生物学的方法,对从濒死异育银鲫肝脏处分离到的菌株YZ-1进行表型生物学、分子生物学及药敏试验的系统研究。【结果】该菌株16S r RNA基因(序列长...【目的】分离鉴定江苏省扬州市养殖场异育银鲫患病病原。【方法】采用常规的理化特性和分子生物学的方法,对从濒死异育银鲫肝脏处分离到的菌株YZ-1进行表型生物学、分子生物学及药敏试验的系统研究。【结果】该菌株16S r RNA基因(序列长度1 446 bp,Gen Bank登录号为JX164202)与其它杀鲑气单胞菌16S r RNA基因一致性在99%-100%之间,构建发育树确定该菌株为杀鲑气单胞菌杀鲑亚种(Aeromonas salmonicida subsp.salmonicida)。人工回感可导致异育银鲫死亡。药敏试验结果显示:对头孢呋辛、复方新诺明、恩诺沙星等23种抗生素敏感;对阿米卡星、四环素、大观霉素、头孢拉定等11种抗生素中度敏感;对青霉素G、链霉素、庆大霉素、氟苯尼考、万古霉素等10种抗生素耐药。【结论】研究结果证实引起异育银鲫死亡的病原为杀鲑气单胞菌杀鲑亚种。展开更多
基金supported by the National Key Research and Development Program of China(2021YFD1800400)the National Natural Science Foundation of China(31872480)+1 种基金the Jiangsu Agriculture Science and Technology Innovation Fund,China(CX(19)2020)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China(PAPD)。
文摘Streptococcus equi subsp.zooepidemicus(SEZ)is an important zoonotic agent.Here,a virulence-attenuated strain M35246 derived from natural variation of wild-type SEZ ATCC35246 was found.M35246 showed a deletion of 25contiguous genes as well as a loss-of-function mutation in covS.Subsequently,a 25-gene-deleted strain(ΔPI),a covS-mutant strain(Mcov S),and relevant complementary strains were constructed and investigated.M35246 and Mcov S were significantly less encapsulated and exhibited poorer anti-phagocytic capacity compared to wild-type SEZ.McovS was significantly more sensitive toβ-lactams,aminoglycosides,macrolides,and lincosamides than wild-type SEZ.M35246,McovS,andΔPI exhibited an increase in median lethal dose(LD_(50))in mice by 10~5,10~5,and 5 times when compared to wild-type SEZ,respectively.Neither M35246 nor McovS were isolated from mice 48 h after being challenged with approximately 2000 times the LD_(50)of wild-type SEZ.Transcriptome analysis showed that 668 significantly differentially expressed genes existed between McovS and wild-type SEZ.Numerous virulence factor-encoding genes and anabolicrelated genes in McovS that were involved in anti-phagocytosis,capsule formation,pathogenicity,and antibiotic resistance were downregulated significantly relative to the wild-type strain.This study revealed that the CovS plays a vital role in the establishment of SEZ virulence.
文摘1)Bifidobacterium longum subsp.iuvenis(Modesto et al.IJSEM.2023,73:6013;Type strain:NCC 5000 T=CCOS 2034 T=LMG 32752^(T))Etymology:iu’ve.nis.L.gen.masc./fem.n.iuvenis,of child,because the type strain was isolated from a 2 year old Bangladeshi child.长双歧杆菌幼儿亚种.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFD1200101)the Earmarked Fund for Modern Agro-industry Technology Research System(Grant No.CARS-23)Science and Technology Innovation Program of the Chinese Academy of Agricultural Science(Grant No.CAAS-ASTIP-IVFCAAS).
文摘Bacterial soft rot(BSR)caused by Pectobacterium carotovorum subsp.brasiliense(Pcb)is a serious bacterial disease which negatively impact yield and quality in cucumber.However,the genetic mechanism of BSR resistance in cucumber has not been reported.Here,we investigated the BSR resistance of 119 cucumber core germplasm worldwide at the seedling stage and identified 26 accessions highly resistant to BSR.A total of 1642740 single-nucleotide polymorphisms(SNPs)were used to conduct GWAS,and five loci associated with BSR resistance were detected on four chromosomes:gBSR2.1,gBSR2.2,gBSR3.1,gBSR4.1 and gBSR5.1.Based on haplotype analysis,sequence polymorphisms,functional annotation and qRT-PCR analysis,six candidate genes were identified within the five loci.CsaV3_2G014450,CsaV3_2G014490,CsaV3_2G016000,CsaV3_3G000850,CsaV3_4G033150,and CsaV3_5G000390 each had nonsynonymous SNPs,and were significantly up-regulated in the resistant genotypes after inoculation.And CsaV3_5G000390 in the susceptible genotype was significantly up-regulated after inoculation.The identification of these candidate genes lays a foundation for understanding the genetic mechanism of BSR resistance in cucumber.Generally,our study mined genes associated with BSR resistance in cucumber seedlings and will assist the breeding of BSR-resistant cucumber cultivars.
基金supported by the National Key R&D Programs of China(2022YFF0710701,2022YFF0710702)Guangzhou Key Research and Development Program(202206010157)+2 种基金Guangzhou Joint Fund for Key Laboratory(202201020381)Medical Joint Fund of Jinan University(YXJC202204)Open Research Project of the Key Laboratory of Viral Pathogenesis and Infection Prevention and Control of the Ministry of Education(2023VPPC-R02).
文摘Background:The maturation of the immune system is critical during early life,as it involves the differentiation,maturation,and establishment of immune tolerance of immune cells.This process is influenced not only by genetic factors but also by en-vironmental factors,particularly the symbiotic microbiota.Bifidobacterium animalis subsp.lactis(BB-12),originally found in dairy products,is widely used in infant for-mula and dietary supplements.However,its role and mechanisms in immune develop-ment during early life remain unclear.Methods:Using GF mice as the experimental model,B.animalis subsp.lactis BB-12 was administered via gavage during early life.In the juvenile stage,changes in T-cell subsets in the spleen,thymus,and gut intraepithelial lymphocytes(IEL)were assessed using spectral flow cytometry.Additionally,targeted metabolomics analysis of trypto-phan metabolism and short-chain fatty acid pathways in colonic tissue was conducted to explore how B.animalis subsp.lactis BB-12 influences the immune system through gut microbiota metabolism.Results:BB-12 effectively modulates the gut immune microenvironment,leading to beneficial changes in T-cell subsets in key immune tissues such as the spleen,thymus,and gut IELs.Metabolomics analysis further supports these findings by showing that BB-12 intervention greatly increased the production of tryptophan derivatives and acetic acid in the colon of GF mice.Conclusion:The findings provide theoretical evidence for the role of B.animalis subsp.lactis in immune system development and support its application in dietary supple-ments,suggesting potential as a component for infant immune health and in prevent-ing immune-related diseases.
基金supported by the National Natural Science Foundation of China(32021005,32272332)the Fundamental Research Funds for the Central Universities(JUSRP622020,JUSRP51501)+1 种基金the Program of Collaborative Innovation Centre of Food Safety and Quality Control in Jiangsu ProvincePostgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX22_2391)。
文摘Bifidobacterium longum subsp.infantis and Bifidobacterium adolescentis play important roles in the guts of infants and adolescents,respectively.In this study,using a neonatal rat model,we compared the protective effects of these 2 bifidobacterial species against Salmonella infection.The results demonstrated that B.longum subsp.infantis was more effective than B.adolescentis in alleviating the severity of infection in newborn rats exposed to Salmonella enterica serovar Typhimurium strain SL1344.B.longum subsp.infantis attenuated intestinal inflammation and mucosal damage induced by Salmonella infection,as well as protecting intestinal nerves and intestinal barrier function through TLR4/My D88 signalling.B.longum subsp.infantis also displayed the potential to modulate gut metabolites by promoting the biosynthesis of unsaturated fatty acids(arachidonic acid,eicosapentaenoic acid andα-linolenic acid)and purine metabolism(guanine,adenine,inosine and adenosine),thereby regulating metabolic disturbances.Additionally,the benefits of B.longum subsp.infantis were also observed in the liver,spleen and brain,improving nerve reflexes and suppressing hepatosplenomegaly.Overall,these findings provide novel insights into the prevention and treatment of gutrelated diseases in newborns,highlighting the potentially significant role of B.longum subsp.infantis in clinical applications.
基金funded by the National Key R&D Program of China(2023YFF1104501)R&D Program of Beijing Municipal Education Commission(23JF0006)National Natural Science Foundation of China(31601443 and 32101938)。
文摘Accumulating evidence suggests that probiotics affect the microbial-gut-brain axis in a way that can prevent and treat Alzheimer's disease(AD).However,the mechanism underlying the therapeutic effects still needs to be further investigated.This study aimed to examine the alleviating effect of Lacticaseibacillus paracasei L9 and Bifidobacterium animalis subsp.lactis A6 and possible mechanism in mice with AD.In this study,the administration of probiotics L9 and A6 effectively improved memory and learning functions in AD mice.The hippocampal cells of mice were partly recovered in morphology and rearranged more neatly after probiotics intervention.Meanwhile,L9 and A6 exhibited inhibitory effects on the phosphorylation of Tau and the deposition of Aβ,which were mediated via GSK-3βand PP2A kinases.Meanwhile,by metagenomic sequencing,we found interventions with L9 and A6 altered the intestinal microbiome's taxonomic composition,reduced the abundance of pathogenic Desulfovibrio genera,and increased beneficial Clostridium and Paramuribaculum genera abundance.The fatty acids metabolism and biosynthesis of gut microbiome were also enhanced.Serum untargeted metabolomics also showed noticeable alternation in lipidrelated metabolites,which may alleviate the pathogenesis of AD.These results revealed a mitigating role for probiotic L9 and A6 in AD prevention and offer new insights into AD prevention via gut-brain connection.
基金funded by the National Key R&D Program of China(2021YFD2100700)National Natural Science Foundation of China(32021005)+1 种基金111 project(BP0719028)Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province。
文摘Bifidobacterium longum subsp.infantis is a commensal bacterium that predominates in the infant gut,playing a critical role in both preventing foreign infections and facilitating immune development.This study aimed to explore the effects of B.longum subsp.infantis supplementation on interferon-beta(IFN-β)secretion and intestinal barrier improvement in growing mice.Female and male mice were orally administered either saline or B.longum subsp.infantis CCFM1269 or I5TI(1×10^(9) CFU/mice per day,n=8)from 1-week-age until 3-,4-,and 5-week-age.RNA sequencing analysis revealed that CCFM1269 exhibited potential antiviral capacity through increasing 2'-5'oligoadenylate synthetase(OAS).Additionally,CCFM1269 supplementation significantly increased colonic IFN-β levels which combined with OAS in 3-week-old female and male mice by activating the TLR4-TRIF-dependent signaling pathway.However,this effect was not observed in 4-and 5-week-old mice.Furthermore,both CCFM1269 were found to modulate the gut microbiota composition and enhance the intestinal barrier function in 3-,4-,and 5-week-old mice.In summary,the results of this study suggested that B.longum subsp.infantis CCFM1269 promoting intestinal barrier and releasing IFN-β in growing mice was in a strain-specific and time-dependent manner.
文摘【目的】分离鉴定江苏省扬州市养殖场异育银鲫患病病原。【方法】采用常规的理化特性和分子生物学的方法,对从濒死异育银鲫肝脏处分离到的菌株YZ-1进行表型生物学、分子生物学及药敏试验的系统研究。【结果】该菌株16S r RNA基因(序列长度1 446 bp,Gen Bank登录号为JX164202)与其它杀鲑气单胞菌16S r RNA基因一致性在99%-100%之间,构建发育树确定该菌株为杀鲑气单胞菌杀鲑亚种(Aeromonas salmonicida subsp.salmonicida)。人工回感可导致异育银鲫死亡。药敏试验结果显示:对头孢呋辛、复方新诺明、恩诺沙星等23种抗生素敏感;对阿米卡星、四环素、大观霉素、头孢拉定等11种抗生素中度敏感;对青霉素G、链霉素、庆大霉素、氟苯尼考、万古霉素等10种抗生素耐药。【结论】研究结果证实引起异育银鲫死亡的病原为杀鲑气单胞菌杀鲑亚种。
