Carbapenemase-producing Enterobacteriaceae(CPE) isolates are recognized as one of the most severe threats to public health. However, the population structure and genetic characteristics of CPE isolates among bloodstre...Carbapenemase-producing Enterobacteriaceae(CPE) isolates are recognized as one of the most severe threats to public health. However, the population structure and genetic characteristics of CPE isolates among bloodstream infections(BSIs) are largely unknown. To address this knowledge gap, in this study,we included patients with clinically significant BSIs due to Enterobacterales isolates, recruited from 26 sentinel hospitals in China(2014–2015). CPE isolates were microbiologically and genomically characterized,including their susceptibility profiles, molecular typing, phylogenetic features, and genetic context analysis of carbapenemase-encoding genes. Of the 2569 BSI Enterobacterales isolates enrolled, 42(1.6%) were carbapenemase-positive. Moreover, among the 2242 investigated isolates, 1111(49.6%) extendedspectrum β-lactamase(ESBL)-producing isolates were identified in Escherichia coli(E. coli), Klebsiella pneumoniae(K. pneumoniae), Proteus mirabilis(P. mirabilis), and Klebsiella oxytoca. Whole genome sequencing analysis showed the clonal spread of K. pneumoniae carbapenemase(KPC)-2-producing K. pneumoniae sequence type(ST) 11 and New Delhi metallo-β-lactamase(NDM)-5-producing E. coli ST167 in our collection. Plasmid analysis revealed that carbapenemase-encoding genes were located on multiple plasmids. A high prevalence of biofilm-encoding type 3 fimbriae clusters and yesiniabactin-associated genes was observed in K. pneumoniae isolates. This work demonstrates the high prevalence of ESBLs and the wide dissemination of CPE among BSI isolates in China, which represent real clinical threats. Moreover, our findings first illustrate a more comprehensive genome scenario of CPE isolates among BSIs. The clonal spread of KPC-2-producing K. pneumoniae ST11 and NDM-5-producing E. coli ST167 needs to be closely monitored.展开更多
Breast cancer,recognized as a foremost cause of mortality among women,is characterized by a complex immune microenvironment.Alternative splicing(AS)is a crucial process leading to diverse transcript variants.Studies h...Breast cancer,recognized as a foremost cause of mortality among women,is characterized by a complex immune microenvironment.Alternative splicing(AS)is a crucial process leading to diverse transcript variants.Studies have shown As's role in T cell and B cell stimulation.For instance,Shalek et al performed single-cell RNA sequencing and showed that different AS patterns existed depending on the maturity and differentiation of dendritic cells,such as Cxcl10.展开更多
NDM-1(New Delhi metallo-beta-lactamase)gene encodes a metallo-beta-lactamase(MBL)with high carbapenemase activity,which makes the host bacterial strain easily dispatch the last-resort antibiotics known as carbapenems ...NDM-1(New Delhi metallo-beta-lactamase)gene encodes a metallo-beta-lactamase(MBL)with high carbapenemase activity,which makes the host bacterial strain easily dispatch the last-resort antibiotics known as carbapenems and cause global concern.Here we present the bioinformatics data showing an unexpected similarity between NDM-1 and beta-lactamase II from Erythrobacter litoralis,a marine microbial isolate.We have further expressed these two mature proteins in E.coli cells,both of which present as a monomer with a molecular mass of 25 kDa.Antimicrobial susceptibility assay reveals that they share similar substrate specificities and are sensitive to aztreonam and tigecycline.The conformational change accompanied with the zinc binding visualized by nuclear magnetic resonance,Zn2+-bound NDM-1,adopts at least some stable tertiary structure in contrast to the metal-free protein.Our work implies a close evolutionary relationship between antibiotic resistance genes in environmental reservoir and in the clinic,challenging the antimicrobial resistance monitoring.展开更多
Bacterial cell division is strictly regulated in the formation of equal daughter cells. This process is governed by a series of spatial and temporal regulators, and several new factors of interest to the field have re...Bacterial cell division is strictly regulated in the formation of equal daughter cells. This process is governed by a series of spatial and temporal regulators, and several new factors of interest to the field have recently been identified. Here, we report the requirement of gluconate 5-dehydrogenase （Ga5DH） in cell division of the zoonotic pathogen Strepto- coccus suis. GaSDH catalyzes the reversible reduction of 5-ketogluconate to D-gluconate and was localized to the site of cell division. The deletion of Ga5DH in S. suis resulted in a plump morphology with aberrant septa joining the progeny. A significant increase was also observed in cell length. These defects were determined to be the conse- quence of Ga5DH deprivation in S. suis causing FtsZ delo- calization. In addition, the interaction of FtsZ with Ga5DH in vitro was confirmed by protein interaction assays. These results indicate that GaSDH may function to prevent the formation of ectopic Z rings during S. suis cell division.展开更多
Professor Tingbin Yang(杨廷彬)has dedicated his whole life to education science and microbiology research.He is not only an excellent microbiologist but also an outstanding educator.He has finished many professional b...Professor Tingbin Yang(杨廷彬)has dedicated his whole life to education science and microbiology research.He is not only an excellent microbiologist but also an outstanding educator.He has finished many professional books and got several honors for his job.Prof.Yang has contributed a lot for the development of medical laboratory education in China and clinical medicine.展开更多
基金the financial support of the National Key Research and Development Program of China (2017YFC1200203 and 2016YFD0501105)the Mega-projects of Science Research of China (2018ZX10733402-004 and 2018ZX10712001-005)+2 种基金the National Natural Science Foundation of China (81741098 and 81711530049)the Zhejiang Provincial Key Research and Development Program (2015C03032)the Zhejiang Provincial Natural Science Foundation of China (LY17H190003)
文摘Carbapenemase-producing Enterobacteriaceae(CPE) isolates are recognized as one of the most severe threats to public health. However, the population structure and genetic characteristics of CPE isolates among bloodstream infections(BSIs) are largely unknown. To address this knowledge gap, in this study,we included patients with clinically significant BSIs due to Enterobacterales isolates, recruited from 26 sentinel hospitals in China(2014–2015). CPE isolates were microbiologically and genomically characterized,including their susceptibility profiles, molecular typing, phylogenetic features, and genetic context analysis of carbapenemase-encoding genes. Of the 2569 BSI Enterobacterales isolates enrolled, 42(1.6%) were carbapenemase-positive. Moreover, among the 2242 investigated isolates, 1111(49.6%) extendedspectrum β-lactamase(ESBL)-producing isolates were identified in Escherichia coli(E. coli), Klebsiella pneumoniae(K. pneumoniae), Proteus mirabilis(P. mirabilis), and Klebsiella oxytoca. Whole genome sequencing analysis showed the clonal spread of K. pneumoniae carbapenemase(KPC)-2-producing K. pneumoniae sequence type(ST) 11 and New Delhi metallo-β-lactamase(NDM)-5-producing E. coli ST167 in our collection. Plasmid analysis revealed that carbapenemase-encoding genes were located on multiple plasmids. A high prevalence of biofilm-encoding type 3 fimbriae clusters and yesiniabactin-associated genes was observed in K. pneumoniae isolates. This work demonstrates the high prevalence of ESBLs and the wide dissemination of CPE among BSI isolates in China, which represent real clinical threats. Moreover, our findings first illustrate a more comprehensive genome scenario of CPE isolates among BSIs. The clonal spread of KPC-2-producing K. pneumoniae ST11 and NDM-5-producing E. coli ST167 needs to be closely monitored.
基金supported by the National Key Research and Development Program of China (No.2023YFF1204600)the Guangdong Province Basic and Applied Basic Research Fund (China) (No.2022A1515110765)+1 种基金the National Natural Science Foundation of China (No.32270710)the Outstanding Youth Foundation of Heilongjiang Province of China (No.YQ2021H005).
文摘Breast cancer,recognized as a foremost cause of mortality among women,is characterized by a complex immune microenvironment.Alternative splicing(AS)is a crucial process leading to diverse transcript variants.Studies have shown As's role in T cell and B cell stimulation.For instance,Shalek et al performed single-cell RNA sequencing and showed that different AS patterns existed depending on the maturity and differentiation of dendritic cells,such as Cxcl10.
基金the Innovative Research Group of the National Natural Science Foundation of China(Grant No.81021003)Work in GFG's laboratory is supported,in part,by the National Basic Research Program(973 Project)from China Ministry of Science and Technology(Grant No.2011CB504703)。
文摘NDM-1(New Delhi metallo-beta-lactamase)gene encodes a metallo-beta-lactamase(MBL)with high carbapenemase activity,which makes the host bacterial strain easily dispatch the last-resort antibiotics known as carbapenems and cause global concern.Here we present the bioinformatics data showing an unexpected similarity between NDM-1 and beta-lactamase II from Erythrobacter litoralis,a marine microbial isolate.We have further expressed these two mature proteins in E.coli cells,both of which present as a monomer with a molecular mass of 25 kDa.Antimicrobial susceptibility assay reveals that they share similar substrate specificities and are sensitive to aztreonam and tigecycline.The conformational change accompanied with the zinc binding visualized by nuclear magnetic resonance,Zn2+-bound NDM-1,adopts at least some stable tertiary structure in contrast to the metal-free protein.Our work implies a close evolutionary relationship between antibiotic resistance genes in environmental reservoir and in the clinic,challenging the antimicrobial resistance monitoring.
文摘Bacterial cell division is strictly regulated in the formation of equal daughter cells. This process is governed by a series of spatial and temporal regulators, and several new factors of interest to the field have recently been identified. Here, we report the requirement of gluconate 5-dehydrogenase （Ga5DH） in cell division of the zoonotic pathogen Strepto- coccus suis. GaSDH catalyzes the reversible reduction of 5-ketogluconate to D-gluconate and was localized to the site of cell division. The deletion of Ga5DH in S. suis resulted in a plump morphology with aberrant septa joining the progeny. A significant increase was also observed in cell length. These defects were determined to be the conse- quence of Ga5DH deprivation in S. suis causing FtsZ delo- calization. In addition, the interaction of FtsZ with Ga5DH in vitro was confirmed by protein interaction assays. These results indicate that GaSDH may function to prevent the formation of ectopic Z rings during S. suis cell division.
文摘Professor Tingbin Yang(杨廷彬)has dedicated his whole life to education science and microbiology research.He is not only an excellent microbiologist but also an outstanding educator.He has finished many professional books and got several honors for his job.Prof.Yang has contributed a lot for the development of medical laboratory education in China and clinical medicine.
