Magnaporthe oryzae is the causal agent of rice blast. Glycosylation plays key roles in vegetative growth,development, and infection of M. oryzae. However, several glycosylation-related genes have not been characterize...Magnaporthe oryzae is the causal agent of rice blast. Glycosylation plays key roles in vegetative growth,development, and infection of M. oryzae. However, several glycosylation-related genes have not been characterized.In this study, we identified a Glyco_transf_22 domain-containing protein, MoAlg9, and found that MoAlg9 islocalized to the endoplasmic reticulum(ER). Deletion of MoALG9 significantly affected conidial production, normalappressorium formation, responses to stressors, and pathogenicity of M. oryzae. We also found that the ΔMoalg9mutant was defective in glycogen utilization, appressorial penetration, and invasive growth in host cells. Moreover,we further demonstrated that MoALG9 regulates the transcription of several target genes involved in conidiation,appressorium formation, and cell wall integrity. In addition, we found that the Glyco_transf_22 domain is essentialfor normal MoAlg9 function and localization. We also provide evidence that MoAlg9 is involved in N-glycosylationpathway in M. oryzae. Taken together, these results show that MoAlg9 is important for conidiation, appressoriumformation, maintenance of cell wall integrity, and the pathogenesis of M. oryzae.展开更多
Oxidation of self-stored carbohydrates and lipids provides the energy for the rapid morphogenetic transformation during asexual and infection-related development in Pyricularia oryzae,which results in intracellular ac...Oxidation of self-stored carbohydrates and lipids provides the energy for the rapid morphogenetic transformation during asexual and infection-related development in Pyricularia oryzae,which results in intracellular accumulation of reducing equivalents NADH and FADH_(2),requiring a cytosolic shuttling machinery towards mitochondria.Our previous studies identified the mitochondrial D-lactate dehydrogenase MoDld1 as a regulator to channel the metabolite flow in conjunction with redox homeostasis.However,the regulator(s)facilitating the cytosolic redox balance and the importance in propelling nutrient metabolite flow remain unknown.The G-3-P shuttle is a conserved machinery transporting the cytosolic reducing power to mitochondria.In P.oryzae,the mitochondrial G-3-P dehydrogenase Gpd2 was required for cellular NAD^(+)/NADH balance and fungal virulence.In this study,we relocate the mitochondrial G-3-P dehydrogenase Gpd2 to the cytosol for disturbing cytosolic redox status.Our results showed overexpression of cytosolic gpd2^(Δmts)without the mitochondrial targeted signal(MTS)driven by Ribosomal protein 27 promoter(PR27)exerted conflicting regulation of cellular oxidoreductase activities compared to theΔModld1 deletion mutant by RNA-seq and prevented the conidiation and pathogenicity of P.oryzae.Moreover,overexpression of gpd2^(Δmts)caused defects in glycogen and lipid mobilization underlying asexual and infectious structural development associated with decreased cellular NADH production and weakened anti-oxidation activities.RNA-seq and non-targeted metabolic profiling revealed down-regulated transcriptional activities of carbohydrate metabolism and lower abundance of fatty acids and secondary metabolites in RP27:gpd2^(Δmts).Thus,our studies indicate the essential role of cytosolic redox control in nutrient metabolism fueling the asexual and infection-related development in P.oryzae.展开更多
Xanthomonas oryzae pv.oryzae(Xoo)causes bacterial blight in rice,which reduces crop yield and leads to significant economic losses.Bacterial sigma(σ)factors are highly specialized proteins that allow RNA polymerase t...Xanthomonas oryzae pv.oryzae(Xoo)causes bacterial blight in rice,which reduces crop yield and leads to significant economic losses.Bacterial sigma(σ)factors are highly specialized proteins that allow RNA polymerase to recognize and bind to specific promoters.σ^(70) factors also regulate the expression of genes involved in stress response and virulence.However,the role of RpoD in Xoo is still unclear.In this study,we found thatσ^(70) factor RpoD is quite conservative among phytopathogenic bacteria,especially in Xanthomonas sp.In Xoo,PXO_RpoD plays an important role in oxidative stress tolerance and cell motility,as well as being essential for full virulence.Cleavage under targets and tagmentation(CUT&Tag)analyses indicated that RpoD mediates the type three secretion system(T3SS)by regulating the regulation of hrpG and hrpX.By performing bacterial one-hybrid and electrophoretic mobility assay(EMSA),we observed that RpoD directly bound to the promoters of hrpG and hrpX.Collectively,these results demonstrate the transcriptional mechanism and pathogenic functions of RpoD in regulating cell motility and oxidative stress response,providing novel insights into potential targets for disease control.展开更多
Avirulence effectors(Avrs),encoded by plant pathogens,can be recognized by plants harboring the corresponding resistance proteins,thereby initiating effector-triggered immunity(ETI).In susceptible plants,however,Avrs ...Avirulence effectors(Avrs),encoded by plant pathogens,can be recognized by plants harboring the corresponding resistance proteins,thereby initiating effector-triggered immunity(ETI).In susceptible plants,however,Avrs can function as effectors,facilitating infection via effector-triggered susceptibility(ETS).Mechanisms of Avr-mediated ETS remain largely unexplored.Here we report that the Magnaporthe oryzae effector Avr-PikD enters rice cells via the canonical cytoplasmic secretion pathway and suppresses rice basal defense.Avr-PikD interacts with an LSD1-like transcriptional activator AKIP30 of rice,and AKIP30 is also a positive regulator of rice immunity,whereas Avr-PikD impedes its nuclear localization and suppresses its transcriptional activity.In summary,M.oryzae delivers Avr-PikD into rice cells to facilitate ETS by inhibiting AKIP30-mediated transcriptional regulation of immune response against M.oryzae.展开更多
The fungal disease caused by Magnaporthe oryzae is one of the most devastating diseases that endanger many crops worldwide.Evidence shows that sexual reproduction can be advantageous for fungal diseases as hybridizati...The fungal disease caused by Magnaporthe oryzae is one of the most devastating diseases that endanger many crops worldwide.Evidence shows that sexual reproduction can be advantageous for fungal diseases as hybridization facilitates host-jumping.However,the pervasive clonal lineages of M.oryzae observed in natural fields contradict this expectation.A better understanding of the roles of recombination and the fungi-specific repeat-induced point mutation(RIP)in shaping its evolutionary trajectory is essential to bridge this knowledge gap.Here we systematically investigate the RIP and recombination landscapes in M.oryzae using a whole genome sequencing data from 252 population samples and 92 cross progenies.Our data reveal that the RIP can robustly capture the population history of M.oryzae,and we provide accurate estimations of the recombination and RIP rates across different M.oryzae clades.Significantly,our results highlight a parent-of-origin bias in both recombination and RIP rates,tightly associating with their sexual potential and variations of effector proteins.This bias suggests a critical trade-off between generating novel allelic combinations in the sexual cycle to facilitate host-jumping and stimulating transposon-associated diversification of effectors in the asexual cycle to facilitate host coevolution.These findings provide unique insights into understanding the evolution of blast fungus.展开更多
A series of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkylamination derivatives was rationally synthesized based on diversity-oriented synthesis via cross coupling of 1,3-dienes,amines and fluoroalky...A series of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkylamination derivatives was rationally synthesized based on diversity-oriented synthesis via cross coupling of 1,3-dienes,amines and fluoroalkyl iodides.The reaction featured good function group tolerance and a broad substrate scope,which could be extended to the late-stage modification of bioactive molecules.Bactericidal activity of all the compounds against Xanthomonas oryzae pv.oryzae(Xoo)was evaluated.Among them,compound E14 showed significant activity against Xanthomonas oryzae pv.oryzae(Xoo)with half maximal effective concentration(EC50)value of 6.61μmol/mL.In pot experiments,the results showed that E14 could control rice bacterial blight with protective and curative efficiencies of 37.5%and 63.2%at 200μg/mL,respectively.Additionally,a plausible mechanism for antibacterial behavior of E14 was proposed by electron microscopy,flow cytometry,reactive oxygen species detection,and biofilm assay.In current work,it can promote the development of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkyl amination compounds as prospective antibacterial agent bearing an intriguing mode of action.展开更多
ZnS and ZnS:3.125%Ce^(3+)(ZSC)quantum dots(QDs)were synthesized by a low-temperature solid-phase method.The crystal structure,photoluminescence(PL)properties of ZSC QDs,and their effects on the growth and kojic acid p...ZnS and ZnS:3.125%Ce^(3+)(ZSC)quantum dots(QDs)were synthesized by a low-temperature solid-phase method.The crystal structure,photoluminescence(PL)properties of ZSC QDs,and their effects on the growth and kojic acid production of Aspergillus oryzae(A.oryzae)were investigated.It is found that both QDs have a cubic blend structure with the average particle size ranging of 2.75-6.14 nm.Ce^(3+)doping not only increases the band gap of ZnS QDs from 3.43 to 3.48 eV,but also increases the PL intensity by about 2.23 times,which is due to the fact that the electron carrier concentration is improved,and then the rate of radiative recombination is increased.The integral emission intensity,biomass,extracellular proteins yield,and kojic acid production of A.oryzae cultured with ZSC(ZnS)QDs are about 4.31(3.23),1.61(1.20),1.12(1.09),and 2.99(1.68)times higher than that of medium without QDs,respectively.展开更多
The conserved DNA damage repair complex,MMS21-SMC5/6(Methyl methane sulfonate 21-Structural maintenance of chromosomes 5/6),has been extensively studied in yeast,animals,and plants.However,its role in phytopathogenic ...The conserved DNA damage repair complex,MMS21-SMC5/6(Methyl methane sulfonate 21-Structural maintenance of chromosomes 5/6),has been extensively studied in yeast,animals,and plants.However,its role in phytopathogenic fungi,particularly in the highly destructive rice blast fungus Magnaporthe oryzae,remains unknown.In this study,we functionally characterized the homologues of this complex,MoMMS21 and MoSMC5,in M.oryzae.We first demonstrated the importance of DNA damage repair in M.oryzae by showing that the DNA damage inducer phleomycin inhibited vegetative growth,infection-related development and pathogenicity in this fungus.Additionally,we discovered that MoMMS21 and MoSMC5 interacted in the nuclei,suggesting that they also function as a complex in M.oryzae.Gene deletion experiments revealed that both MoMMS21 and MoSMC5 are required for infection-related development and pathogenicity in M.oryzae,while only MoMMS21 deletion affected growth and sensitivity to phleomycin,indicating its specific involvement in DNA damage repair.Overall,our results provide insights into the roles of MoMMS21 and MoSMC5 in M.oryzae,highlighting their functions beyond DNA damage repair.展开更多
Nowadays,the application of Fungi as a bio-mediated soil improvement technique is developing.The hydraulic properties of Rhizopus Fungi-Mycelium Treated Soil are unknown,and the treated sample tends to have low durabi...Nowadays,the application of Fungi as a bio-mediated soil improvement technique is developing.The hydraulic properties of Rhizopus Fungi-Mycelium Treated Soil are unknown,and the treated sample tends to have low durability.This article presents experimental results on the hydraulic conductivity and shear strength of Fungi-mycelium-treated silica sand.The fungi used in the experiments are a combination ofRhizopus oligosporus andRhizopus oryzae,which are popular for making Tempeh,a local soybean cuisine from Indonesia.The samples were prepared by mixing the sand with Tempeh inoculum at various treatments and Tempe inoculum and rice flour dosages for enhancing the durability of the treated soil.The results showed that the saturated permeability of the treated soil could be reduced by about 10 times compared to the untreated soil.In addition,the Soil-Water Characteristic Curve of the treated soil also developed.The effect of the fungi appears to fill the void of soil and hence increases the Air Entry Value and residual suction of soil.The curing method outside the mold(O-method)with 10%Tempeh inoculum,and 5%Tempeh inoculum with 5%rice flour is proven can extend the durability of the treated sample,the undrained compressive strength is about 40 kPa on day 14.Scanning electron microscope was performed on the samples,which lasted for 4 months.The mycelium and hyphae are still clearly seen covering all sand particles with different percentages of Tempeh inoculum and rice flour.When the mycelium covered all the sand particles and filled the pores,the water flow was partially blocked.It might be attributed to the strong hydrophobicity of the fungi,which could prevent water from penetrating the soil.展开更多
The polymerase chain reaction(PCR) is particularly useful for plant pathogen detection. In the present study, multiplex PCR and SYBR Green real-time PCR were developed to facilitate the simultaneous detection of three...The polymerase chain reaction(PCR) is particularly useful for plant pathogen detection. In the present study, multiplex PCR and SYBR Green real-time PCR were developed to facilitate the simultaneous detection of three important rice pathogens, Xanthomonas oryzae pv.oryzae, X. oryzae pv. oryzicola, and Burkholderia glumae. The unique PCR primer sets were designed from portions of a putative glycosyltransferase gene of X. oryzae pv. oryzae, an Avr Rxo gene of X. oryzae pv. oryzicola, and an internal transcribed spacer(ITS) sequence of B. glumae. Using a multiplex PCR assay, X. oryzae pv. oryzae, X. oryzae pv. oryzicola, and B. glumae were detected in one PCR reaction that contained the newly developed primer set mix. Using SYBR Green real-time PCR assays, X. oryzae pv. oryzae, X. oryzae pv. oryzicola, and B. glumae were detected at 1, 1, and 10 fg μL-1, respectively. These newly designed molecular assays are sensitive and could be reliable tools for pathogen detection and disease forecasting.展开更多
[Objective] The research aimed to isolate the glyphosate-degraded strain and study its degradation characteristics.[Method] A glyphosate-degraded fungal strain A-F02 was isolated from sludge in an aeration tank of a g...[Objective] The research aimed to isolate the glyphosate-degraded strain and study its degradation characteristics.[Method] A glyphosate-degraded fungal strain A-F02 was isolated from sludge in an aeration tank of a glyphosate manufacture.The fungal strain A-F02 was identified according to morphological characteristics and internal transcribed spacer(ITS)region of nuclear ribosomal DNA sequence analysis.The glyphosate-biodegraded characteristics of strain A-F02 and the influencing factors were studied.[Result] The fungal strain A-F02 was identified as Aspergillus oryzae sp..The glyphosate-biodegraded rate was 86.82% in the mineral salt medium with 1 000 mg/L of glyphosate as the sole source of carbon,after being incubated at 30 ℃ and 150 rpm for 7 d.The biodegradation rates and biomass of the A-F02 were the highest under the culture conditions with glucose(0.5%,w/v),pH 7.5,30 ℃ and glyphosate(1 500 mg/L).[Conclusion] The research provided the experimental basis for glyphosate-biodegraded enzyme purification.展开更多
[ Objective] This study was to breed rice cultivars with multi-resistance to Orseolia oryzae (Wood-Mason). [ Method] The Guangxi local cultivar GX-M001 (Jiangchao) with high resistance to Orseolia oryzae (Wood-Ma...[ Objective] This study was to breed rice cultivars with multi-resistance to Orseolia oryzae (Wood-Mason). [ Method] The Guangxi local cultivar GX-M001 (Jiangchao) with high resistance to Orseolia oryzae (Wood-Mason) was used to hybrid with the known resistance cultivars "Kangwenqingzhan" (harboring GM5 gene), OB677( harboring GM3 gene) from Sri Lanka, HT1350 and high yield end quality cultivar " Guiruanzhan". [ Result] Through pyramiding the multi-resistant genes via routine hybridization, the general resistances of the hybrids were remarkably enhanced. The grades of resistance were also improved, many of the combinations were endowed with a resistance at immune level (grade 0) ; and interestingly, the respective hybridization of GX-M001 (high resistance) with OB677( medium resistance) and HT1350(suscepti- ble) also generate two lines at immune level, which is probably the effects of additive effects of genes.[ Conclusion] By routine hybridization, multiple genes were successfully pyramided, thus generating novel rice lines with multiple resistances. For the rice breeding scientists at the grass-roots level, the resistance-resistance pyramiding is an effective approach to breed high resistance cultivars.展开更多
Bacterial blight, caused by Xanthomonas oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice(Oryza sativa L.) worldwide. The type III secretion system(T3SS) of Xoo, encoded by the hrp(hypersensitive...Bacterial blight, caused by Xanthomonas oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice(Oryza sativa L.) worldwide. The type III secretion system(T3SS) of Xoo, encoded by the hrp(hypersensitive response and pathogenicity) genes, plays critical roles in conferring pathogenicity in host rice and triggering a hypersensitive response(HR) in non-host plants. To investigate the major genes conferring the pathogenicity and avirulence of Xoo, we previously constructed a random Tn5-insertion mutant library of Xoo strain PXO99A. We report here the isolation and characterization of a Tn5-insertion mutant PXM69. Tn5-insertion mutants were screened on indica rice JG30, which is highly susceptible to PXO99A, by leaf-cutting inoculation.Four mutants with reduced virulence were obtained after two rounds of screening. Among them, the mutant PXM69 had completely lost virulence to the rice host and ability to elicit HR in non-host tobacco. Southern blotting analysis showed a single copy of a Tn5-insertion in the genome of PXM69. PCR walking and sequencing analysis revealed that the Tn5 transposon was inserted at nucleotide position 70,192–70,201 in the genome of PXO99A, disrupting the type III hrc(hrp-conserved) gene hrcQ, the first gene in the D operon of the hrp cluster in Xoo. To confirm the relationship between the Tn5-insertion and the avirulence phenotype of PXM69, we used the marker exchange mutagenesis to create a PXO99Amutant, ΔhrcQ::KAN, in which the hrcQ was disrupted by a kanamycin-encoding gene cassette at the same site as that of the Tn5-insertion. ΔhrcQ::KAN showed the same phenotype as mutant PXM69. Reintroduction of the wild-type hrcQ gene partially complemented the pathogenic function of PXM69. RT-PCR and cellulase secretion assays showed that the Tn5-disruption of hrcQ did not affect transcription of downstream genes in the D operon and function of the type II secretion system. Our results provide new insights into the pathogenic functions of clustered hrp genes in Xoo.展开更多
基金supported by the National Natural Science Foundation of China (32202253)the Natural Science Foundation of Anhui Higher Education Institutions, China (KJ2020A0102)the Talent Research Project of Anhui Agricultural University, China (rc342001)。
文摘Magnaporthe oryzae is the causal agent of rice blast. Glycosylation plays key roles in vegetative growth,development, and infection of M. oryzae. However, several glycosylation-related genes have not been characterized.In this study, we identified a Glyco_transf_22 domain-containing protein, MoAlg9, and found that MoAlg9 islocalized to the endoplasmic reticulum(ER). Deletion of MoALG9 significantly affected conidial production, normalappressorium formation, responses to stressors, and pathogenicity of M. oryzae. We also found that the ΔMoalg9mutant was defective in glycogen utilization, appressorial penetration, and invasive growth in host cells. Moreover,we further demonstrated that MoALG9 regulates the transcription of several target genes involved in conidiation,appressorium formation, and cell wall integrity. In addition, we found that the Glyco_transf_22 domain is essentialfor normal MoAlg9 function and localization. We also provide evidence that MoAlg9 is involved in N-glycosylationpathway in M. oryzae. Taken together, these results show that MoAlg9 is important for conidiation, appressoriumformation, maintenance of cell wall integrity, and the pathogenesis of M. oryzae.
基金funded by the National Natural Science Foundation of China(32272513 and 31770156)the Natural Sciences and Engineering Research Council of Canada(Discovery Grant,RGPIN-2016-05356)the Canadian Foundation for Innovation(Discovery Grant,227398-2011)。
文摘Oxidation of self-stored carbohydrates and lipids provides the energy for the rapid morphogenetic transformation during asexual and infection-related development in Pyricularia oryzae,which results in intracellular accumulation of reducing equivalents NADH and FADH_(2),requiring a cytosolic shuttling machinery towards mitochondria.Our previous studies identified the mitochondrial D-lactate dehydrogenase MoDld1 as a regulator to channel the metabolite flow in conjunction with redox homeostasis.However,the regulator(s)facilitating the cytosolic redox balance and the importance in propelling nutrient metabolite flow remain unknown.The G-3-P shuttle is a conserved machinery transporting the cytosolic reducing power to mitochondria.In P.oryzae,the mitochondrial G-3-P dehydrogenase Gpd2 was required for cellular NAD^(+)/NADH balance and fungal virulence.In this study,we relocate the mitochondrial G-3-P dehydrogenase Gpd2 to the cytosol for disturbing cytosolic redox status.Our results showed overexpression of cytosolic gpd2^(Δmts)without the mitochondrial targeted signal(MTS)driven by Ribosomal protein 27 promoter(PR27)exerted conflicting regulation of cellular oxidoreductase activities compared to theΔModld1 deletion mutant by RNA-seq and prevented the conidiation and pathogenicity of P.oryzae.Moreover,overexpression of gpd2^(Δmts)caused defects in glycogen and lipid mobilization underlying asexual and infectious structural development associated with decreased cellular NADH production and weakened anti-oxidation activities.RNA-seq and non-targeted metabolic profiling revealed down-regulated transcriptional activities of carbohydrate metabolism and lower abundance of fatty acids and secondary metabolites in RP27:gpd2^(Δmts).Thus,our studies indicate the essential role of cytosolic redox control in nutrient metabolism fueling the asexual and infection-related development in P.oryzae.
基金supported by the National Natural Science Foundation of China(32072379,32001865 and 32202259)。
文摘Xanthomonas oryzae pv.oryzae(Xoo)causes bacterial blight in rice,which reduces crop yield and leads to significant economic losses.Bacterial sigma(σ)factors are highly specialized proteins that allow RNA polymerase to recognize and bind to specific promoters.σ^(70) factors also regulate the expression of genes involved in stress response and virulence.However,the role of RpoD in Xoo is still unclear.In this study,we found thatσ^(70) factor RpoD is quite conservative among phytopathogenic bacteria,especially in Xanthomonas sp.In Xoo,PXO_RpoD plays an important role in oxidative stress tolerance and cell motility,as well as being essential for full virulence.Cleavage under targets and tagmentation(CUT&Tag)analyses indicated that RpoD mediates the type three secretion system(T3SS)by regulating the regulation of hrpG and hrpX.By performing bacterial one-hybrid and electrophoretic mobility assay(EMSA),we observed that RpoD directly bound to the promoters of hrpG and hrpX.Collectively,these results demonstrate the transcriptional mechanism and pathogenic functions of RpoD in regulating cell motility and oxidative stress response,providing novel insights into potential targets for disease control.
基金supported by grants from the National Natural Science Foundation of China(31401692,31901960,32272513,32001976)the Natural Science Foundation of Fujian Province(2019J01766,2023J011418,2020J05177)+3 种基金Fujian Provincial Science and Technology Key Project(2022NZ030014)External Cooperation Program of Fujian Academy of Agricultural Sciences(DWHZ-2024-23)State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crop Opening Project(SKL2019005)Project of Fujian Provincial Department of Education(JAT190627)。
文摘Avirulence effectors(Avrs),encoded by plant pathogens,can be recognized by plants harboring the corresponding resistance proteins,thereby initiating effector-triggered immunity(ETI).In susceptible plants,however,Avrs can function as effectors,facilitating infection via effector-triggered susceptibility(ETS).Mechanisms of Avr-mediated ETS remain largely unexplored.Here we report that the Magnaporthe oryzae effector Avr-PikD enters rice cells via the canonical cytoplasmic secretion pathway and suppresses rice basal defense.Avr-PikD interacts with an LSD1-like transcriptional activator AKIP30 of rice,and AKIP30 is also a positive regulator of rice immunity,whereas Avr-PikD impedes its nuclear localization and suppresses its transcriptional activity.In summary,M.oryzae delivers Avr-PikD into rice cells to facilitate ETS by inhibiting AKIP30-mediated transcriptional regulation of immune response against M.oryzae.
基金funded by the National Natural Science Foundation of China(32270664 and 32170327)the National Key Research and Development Program of China(2023YFD2200102 and 2023YFD2200104)Jiangsu Collaborative Innovation Center for Modern Crop Production。
文摘The fungal disease caused by Magnaporthe oryzae is one of the most devastating diseases that endanger many crops worldwide.Evidence shows that sexual reproduction can be advantageous for fungal diseases as hybridization facilitates host-jumping.However,the pervasive clonal lineages of M.oryzae observed in natural fields contradict this expectation.A better understanding of the roles of recombination and the fungi-specific repeat-induced point mutation(RIP)in shaping its evolutionary trajectory is essential to bridge this knowledge gap.Here we systematically investigate the RIP and recombination landscapes in M.oryzae using a whole genome sequencing data from 252 population samples and 92 cross progenies.Our data reveal that the RIP can robustly capture the population history of M.oryzae,and we provide accurate estimations of the recombination and RIP rates across different M.oryzae clades.Significantly,our results highlight a parent-of-origin bias in both recombination and RIP rates,tightly associating with their sexual potential and variations of effector proteins.This bias suggests a critical trade-off between generating novel allelic combinations in the sexual cycle to facilitate host-jumping and stimulating transposon-associated diversification of effectors in the asexual cycle to facilitate host coevolution.These findings provide unique insights into understanding the evolution of blast fungus.
基金the National Natural Science Foundation of China(No.32072450)the National Science Fund for Distinguished Young Scholars of Guangdong Province(No.2021B1515020107)the International Science and Technology Cooperation Program in Guangdong(Nos.2020A0505100048 and 2022A0505050060).
文摘A series of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkylamination derivatives was rationally synthesized based on diversity-oriented synthesis via cross coupling of 1,3-dienes,amines and fluoroalkyl iodides.The reaction featured good function group tolerance and a broad substrate scope,which could be extended to the late-stage modification of bioactive molecules.Bactericidal activity of all the compounds against Xanthomonas oryzae pv.oryzae(Xoo)was evaluated.Among them,compound E14 showed significant activity against Xanthomonas oryzae pv.oryzae(Xoo)with half maximal effective concentration(EC50)value of 6.61μmol/mL.In pot experiments,the results showed that E14 could control rice bacterial blight with protective and curative efficiencies of 37.5%and 63.2%at 200μg/mL,respectively.Additionally,a plausible mechanism for antibacterial behavior of E14 was proposed by electron microscopy,flow cytometry,reactive oxygen species detection,and biofilm assay.In current work,it can promote the development of photoinduced palladium-catalyzed 1,3-diene-selective fluoroalkyl amination compounds as prospective antibacterial agent bearing an intriguing mode of action.
基金Project supported by the National Natural Science Foundation of China(61964008)the Natural ScienceFoundation of Jiangxi Province,China(20212BAB204017)。
文摘ZnS and ZnS:3.125%Ce^(3+)(ZSC)quantum dots(QDs)were synthesized by a low-temperature solid-phase method.The crystal structure,photoluminescence(PL)properties of ZSC QDs,and their effects on the growth and kojic acid production of Aspergillus oryzae(A.oryzae)were investigated.It is found that both QDs have a cubic blend structure with the average particle size ranging of 2.75-6.14 nm.Ce^(3+)doping not only increases the band gap of ZnS QDs from 3.43 to 3.48 eV,but also increases the PL intensity by about 2.23 times,which is due to the fact that the electron carrier concentration is improved,and then the rate of radiative recombination is increased.The integral emission intensity,biomass,extracellular proteins yield,and kojic acid production of A.oryzae cultured with ZSC(ZnS)QDs are about 4.31(3.23),1.61(1.20),1.12(1.09),and 2.99(1.68)times higher than that of medium without QDs,respectively.
基金Research and Development Program of China(2023YFD1400200)the Natural Science Foundation of Fujian Province,China(2022J01125)+2 种基金the Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests,China(MIMCP-202301)the Fujian Provincial Science and Technology Key Project,China(2022NZ030014)the National Natural Science Foundation of China(NSFC31871914).
文摘The conserved DNA damage repair complex,MMS21-SMC5/6(Methyl methane sulfonate 21-Structural maintenance of chromosomes 5/6),has been extensively studied in yeast,animals,and plants.However,its role in phytopathogenic fungi,particularly in the highly destructive rice blast fungus Magnaporthe oryzae,remains unknown.In this study,we functionally characterized the homologues of this complex,MoMMS21 and MoSMC5,in M.oryzae.We first demonstrated the importance of DNA damage repair in M.oryzae by showing that the DNA damage inducer phleomycin inhibited vegetative growth,infection-related development and pathogenicity in this fungus.Additionally,we discovered that MoMMS21 and MoSMC5 interacted in the nuclei,suggesting that they also function as a complex in M.oryzae.Gene deletion experiments revealed that both MoMMS21 and MoSMC5 are required for infection-related development and pathogenicity in M.oryzae,while only MoMMS21 deletion affected growth and sensitivity to phleomycin,indicating its specific involvement in DNA damage repair.Overall,our results provide insights into the roles of MoMMS21 and MoSMC5 in M.oryzae,highlighting their functions beyond DNA damage repair.
文摘Nowadays,the application of Fungi as a bio-mediated soil improvement technique is developing.The hydraulic properties of Rhizopus Fungi-Mycelium Treated Soil are unknown,and the treated sample tends to have low durability.This article presents experimental results on the hydraulic conductivity and shear strength of Fungi-mycelium-treated silica sand.The fungi used in the experiments are a combination ofRhizopus oligosporus andRhizopus oryzae,which are popular for making Tempeh,a local soybean cuisine from Indonesia.The samples were prepared by mixing the sand with Tempeh inoculum at various treatments and Tempe inoculum and rice flour dosages for enhancing the durability of the treated soil.The results showed that the saturated permeability of the treated soil could be reduced by about 10 times compared to the untreated soil.In addition,the Soil-Water Characteristic Curve of the treated soil also developed.The effect of the fungi appears to fill the void of soil and hence increases the Air Entry Value and residual suction of soil.The curing method outside the mold(O-method)with 10%Tempeh inoculum,and 5%Tempeh inoculum with 5%rice flour is proven can extend the durability of the treated sample,the undrained compressive strength is about 40 kPa on day 14.Scanning electron microscope was performed on the samples,which lasted for 4 months.The mycelium and hyphae are still clearly seen covering all sand particles with different percentages of Tempeh inoculum and rice flour.When the mycelium covered all the sand particles and filled the pores,the water flow was partially blocked.It might be attributed to the strong hydrophobicity of the fungi,which could prevent water from penetrating the soil.
基金support of the National 863 Project (2012AA021601)the New Seedling program for graduate students of Zhejiang Province (2012R409012)
文摘The polymerase chain reaction(PCR) is particularly useful for plant pathogen detection. In the present study, multiplex PCR and SYBR Green real-time PCR were developed to facilitate the simultaneous detection of three important rice pathogens, Xanthomonas oryzae pv.oryzae, X. oryzae pv. oryzicola, and Burkholderia glumae. The unique PCR primer sets were designed from portions of a putative glycosyltransferase gene of X. oryzae pv. oryzae, an Avr Rxo gene of X. oryzae pv. oryzicola, and an internal transcribed spacer(ITS) sequence of B. glumae. Using a multiplex PCR assay, X. oryzae pv. oryzae, X. oryzae pv. oryzicola, and B. glumae were detected in one PCR reaction that contained the newly developed primer set mix. Using SYBR Green real-time PCR assays, X. oryzae pv. oryzae, X. oryzae pv. oryzicola, and B. glumae were detected at 1, 1, and 10 fg μL-1, respectively. These newly designed molecular assays are sensitive and could be reliable tools for pathogen detection and disease forecasting.
文摘[Objective] The research aimed to isolate the glyphosate-degraded strain and study its degradation characteristics.[Method] A glyphosate-degraded fungal strain A-F02 was isolated from sludge in an aeration tank of a glyphosate manufacture.The fungal strain A-F02 was identified according to morphological characteristics and internal transcribed spacer(ITS)region of nuclear ribosomal DNA sequence analysis.The glyphosate-biodegraded characteristics of strain A-F02 and the influencing factors were studied.[Result] The fungal strain A-F02 was identified as Aspergillus oryzae sp..The glyphosate-biodegraded rate was 86.82% in the mineral salt medium with 1 000 mg/L of glyphosate as the sole source of carbon,after being incubated at 30 ℃ and 150 rpm for 7 d.The biodegradation rates and biomass of the A-F02 were the highest under the culture conditions with glucose(0.5%,w/v),pH 7.5,30 ℃ and glyphosate(1 500 mg/L).[Conclusion] The research provided the experimental basis for glyphosate-biodegraded enzyme purification.
基金Supported by National Natural Science Foundation of China(30760117)National Key Technology R &D Program (2007BAD68B01)~~
文摘[ Objective] This study was to breed rice cultivars with multi-resistance to Orseolia oryzae (Wood-Mason). [ Method] The Guangxi local cultivar GX-M001 (Jiangchao) with high resistance to Orseolia oryzae (Wood-Mason) was used to hybrid with the known resistance cultivars "Kangwenqingzhan" (harboring GM5 gene), OB677( harboring GM3 gene) from Sri Lanka, HT1350 and high yield end quality cultivar " Guiruanzhan". [ Result] Through pyramiding the multi-resistant genes via routine hybridization, the general resistances of the hybrids were remarkably enhanced. The grades of resistance were also improved, many of the combinations were endowed with a resistance at immune level (grade 0) ; and interestingly, the respective hybridization of GX-M001 (high resistance) with OB677( medium resistance) and HT1350(suscepti- ble) also generate two lines at immune level, which is probably the effects of additive effects of genes.[ Conclusion] By routine hybridization, multiple genes were successfully pyramided, thus generating novel rice lines with multiple resistances. For the rice breeding scientists at the grass-roots level, the resistance-resistance pyramiding is an effective approach to breed high resistance cultivars.
基金supported by the National Natural Science Foundation of China (No. 31171812)
文摘Bacterial blight, caused by Xanthomonas oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice(Oryza sativa L.) worldwide. The type III secretion system(T3SS) of Xoo, encoded by the hrp(hypersensitive response and pathogenicity) genes, plays critical roles in conferring pathogenicity in host rice and triggering a hypersensitive response(HR) in non-host plants. To investigate the major genes conferring the pathogenicity and avirulence of Xoo, we previously constructed a random Tn5-insertion mutant library of Xoo strain PXO99A. We report here the isolation and characterization of a Tn5-insertion mutant PXM69. Tn5-insertion mutants were screened on indica rice JG30, which is highly susceptible to PXO99A, by leaf-cutting inoculation.Four mutants with reduced virulence were obtained after two rounds of screening. Among them, the mutant PXM69 had completely lost virulence to the rice host and ability to elicit HR in non-host tobacco. Southern blotting analysis showed a single copy of a Tn5-insertion in the genome of PXM69. PCR walking and sequencing analysis revealed that the Tn5 transposon was inserted at nucleotide position 70,192–70,201 in the genome of PXO99A, disrupting the type III hrc(hrp-conserved) gene hrcQ, the first gene in the D operon of the hrp cluster in Xoo. To confirm the relationship between the Tn5-insertion and the avirulence phenotype of PXM69, we used the marker exchange mutagenesis to create a PXO99Amutant, ΔhrcQ::KAN, in which the hrcQ was disrupted by a kanamycin-encoding gene cassette at the same site as that of the Tn5-insertion. ΔhrcQ::KAN showed the same phenotype as mutant PXM69. Reintroduction of the wild-type hrcQ gene partially complemented the pathogenic function of PXM69. RT-PCR and cellulase secretion assays showed that the Tn5-disruption of hrcQ did not affect transcription of downstream genes in the D operon and function of the type II secretion system. Our results provide new insights into the pathogenic functions of clustered hrp genes in Xoo.