Rice blast caused by Magnaporthe oryzae (M. oryzae) is one of the most destructive diseases, which causes significant rice yield losses and affects global food security. To better understand genetic variations among...Rice blast caused by Magnaporthe oryzae (M. oryzae) is one of the most destructive diseases, which causes significant rice yield losses and affects global food security. To better understand genetic variations among different isolates of M. oryzae in nature, we re-sequenced the genomes of two field isolates, CH43 and Zhong-10-8-14, which showed distinct pathogenecity on most of the rice cultivars. Genome-wide genetic variation analysis reveals that ZHONG-10-8-14 exhibits higher sequence variations than CH43. Structural variations (SVs) detection shows that the sequence variations primarily occur in exons and intergenic regions. Bioinformatics analysis for gene variations reveals that many pathogenecity-related pathways are enriched. In addition, 193 candidate effectors with various DNA polymorphisms were identified, including two known effectors AVR-Pik and AVR-Pital. Comparative polymorphism analysis of thirteen randomly selected effectors suggests that the genetic variations of effectors are under positive selection. The expression pattern analysis of several pathogenecity-related variant genes indicates that these genes are differentially regulated in two isolates, with much higher expression levels in Zhong-10-8-14 than CH43. Our data demonstrate that the genetic variations of effectors and pathogenecity-related genes are under positive selection, resulting in the distinct pathogeuicities of CH43 and Zhong- 10-8-14 on rice.展开更多
Staphylococcal superantigen(SAg)toxins are the most notable virulence factors associated with Staphylococcus aureus,which is a pathogen associated with serious community and hospital acquired infections in humans and ...Staphylococcal superantigen(SAg)toxins are the most notable virulence factors associated with Staphylococcus aureus,which is a pathogen associated with serious community and hospital acquired infections in humans and various diseases in animals.Recently,SAg toxins have become a superfamily with 29 types,including staphylococcal enterotoxins(SEs)with emetic activity,SE-like toxins(SEIs)that do not induce emesis in primate models or have yet not been tested,and toxic shock syndrome toxin-1(TSST-1).SEs and SEIs can be subdivided into classical types(SEA to SEE)and novel types(SEG to SEIY,SE01,SE02,SEI26 and SEI27).The genes of SAg toxins are located in diverse accessory genetic elements and share certain structural and biological properties.SAg toxins are heat-stable proteins that exhibit pyrogenicity,superantigenicity and capacity to induce lethal hypersensitivity to endotoxin in humans and animals.They have multiple pathogenicities that can interfere with normal immune function of host,increase the chances of survival and transmission of pathogenic baaeria in host,consequently contribute to the occurrence and development of various infeaions,persistent infeaions or food poisoning.This review focuses on the following aspeas of SAg toxins:(1)superfamily members of classic and novelty discovered staphylococcal SAgs;⑵diversity of gene locations and molecular structural characteristics;(3)biological characteristics and activities;(4)multi-pathogenicity of SAgs in animal and human diseases,including bovine mastitis,swine sepsis,abscesses and skin edema in pig,arthritis and septicemia in poultry,and nosocomial infections and food-borne diseases in humans.展开更多
Bangladesh composes the most polluted air with Dhaka securing the top position. The purpose of the study is the enumeration of the prevalence of pathogenic bacteria in Dhaka city’s air and their antibiotic susceptibi...Bangladesh composes the most polluted air with Dhaka securing the top position. The purpose of the study is the enumeration of the prevalence of pathogenic bacteria in Dhaka city’s air and their antibiotic susceptibility to the common antibiotics. For the sample collection, different selective media was exposed in air where the highest and lowest CFU was 137 and 1 respectively. Pathogens were screened through Hemolysis, DNase and Coagulase test and identified by 16s rRNA sequencing followed by antibiotic susceptibility test. 16s rRNA sequencing revealed that the organisms were <em>Bacillus</em> <em>altitudinis</em> strain 41KF2bT.28, <em>Bacillus licheniformis</em> strain QMA46-2, <em>Bacillus altitudinis</em>, <em>Bacillus pumilis </em>strain BJ-DEBCR-34, <em>Staphylococcus aureus </em>strain TPS3156, <em>Bacillus sp </em>CO16, <em>Pseudomonas sp</em> strain 96LC22 and <em>Shigella dysenteriae</em> strain ATCC 13313. <em>Shigella dysenteriae</em>, <em>Staphylococcus aureus</em> were 81.81% and 54.54% resistant to the antibiotics. Whole-genome sequencing would help to observe mutations in the traits as changes in hemolytic activity were found during pathogenecity tests.展开更多
基金supported by the Chinese Academy of Sciences(Strategic Priority Research Program XDB11020300)National Natural Science Foundation of China(31570252,31601629)+1 种基金the start-up fund of"One Hundred Talents"program of the Chinese Academy of Sciences and by the grants from the State Key Laboratory of Plant Genomics(O8KF021011)the Key Laboratory of Urban Agriculture(North)of Ministry of Agriculture of China Beijing University of Agriculture(KFK2015001)
文摘Rice blast caused by Magnaporthe oryzae (M. oryzae) is one of the most destructive diseases, which causes significant rice yield losses and affects global food security. To better understand genetic variations among different isolates of M. oryzae in nature, we re-sequenced the genomes of two field isolates, CH43 and Zhong-10-8-14, which showed distinct pathogenecity on most of the rice cultivars. Genome-wide genetic variation analysis reveals that ZHONG-10-8-14 exhibits higher sequence variations than CH43. Structural variations (SVs) detection shows that the sequence variations primarily occur in exons and intergenic regions. Bioinformatics analysis for gene variations reveals that many pathogenecity-related pathways are enriched. In addition, 193 candidate effectors with various DNA polymorphisms were identified, including two known effectors AVR-Pik and AVR-Pital. Comparative polymorphism analysis of thirteen randomly selected effectors suggests that the genetic variations of effectors are under positive selection. The expression pattern analysis of several pathogenecity-related variant genes indicates that these genes are differentially regulated in two isolates, with much higher expression levels in Zhong-10-8-14 than CH43. Our data demonstrate that the genetic variations of effectors and pathogenecity-related genes are under positive selection, resulting in the distinct pathogeuicities of CH43 and Zhong- 10-8-14 on rice.
基金This study was supported in part by the JSPS KAKENHI Grant numbers 19590438(D.H.)21590475(D.H.)+1 种基金24590516(D.H.)16H05030(D.H.).
文摘Staphylococcal superantigen(SAg)toxins are the most notable virulence factors associated with Staphylococcus aureus,which is a pathogen associated with serious community and hospital acquired infections in humans and various diseases in animals.Recently,SAg toxins have become a superfamily with 29 types,including staphylococcal enterotoxins(SEs)with emetic activity,SE-like toxins(SEIs)that do not induce emesis in primate models or have yet not been tested,and toxic shock syndrome toxin-1(TSST-1).SEs and SEIs can be subdivided into classical types(SEA to SEE)and novel types(SEG to SEIY,SE01,SE02,SEI26 and SEI27).The genes of SAg toxins are located in diverse accessory genetic elements and share certain structural and biological properties.SAg toxins are heat-stable proteins that exhibit pyrogenicity,superantigenicity and capacity to induce lethal hypersensitivity to endotoxin in humans and animals.They have multiple pathogenicities that can interfere with normal immune function of host,increase the chances of survival and transmission of pathogenic baaeria in host,consequently contribute to the occurrence and development of various infeaions,persistent infeaions or food poisoning.This review focuses on the following aspeas of SAg toxins:(1)superfamily members of classic and novelty discovered staphylococcal SAgs;⑵diversity of gene locations and molecular structural characteristics;(3)biological characteristics and activities;(4)multi-pathogenicity of SAgs in animal and human diseases,including bovine mastitis,swine sepsis,abscesses and skin edema in pig,arthritis and septicemia in poultry,and nosocomial infections and food-borne diseases in humans.
文摘Bangladesh composes the most polluted air with Dhaka securing the top position. The purpose of the study is the enumeration of the prevalence of pathogenic bacteria in Dhaka city’s air and their antibiotic susceptibility to the common antibiotics. For the sample collection, different selective media was exposed in air where the highest and lowest CFU was 137 and 1 respectively. Pathogens were screened through Hemolysis, DNase and Coagulase test and identified by 16s rRNA sequencing followed by antibiotic susceptibility test. 16s rRNA sequencing revealed that the organisms were <em>Bacillus</em> <em>altitudinis</em> strain 41KF2bT.28, <em>Bacillus licheniformis</em> strain QMA46-2, <em>Bacillus altitudinis</em>, <em>Bacillus pumilis </em>strain BJ-DEBCR-34, <em>Staphylococcus aureus </em>strain TPS3156, <em>Bacillus sp </em>CO16, <em>Pseudomonas sp</em> strain 96LC22 and <em>Shigella dysenteriae</em> strain ATCC 13313. <em>Shigella dysenteriae</em>, <em>Staphylococcus aureus</em> were 81.81% and 54.54% resistant to the antibiotics. Whole-genome sequencing would help to observe mutations in the traits as changes in hemolytic activity were found during pathogenecity tests.