Project description:Neisseria meningitidis is the leading cause of bacterial meningitis and septicemia worldwide. The novel ST-4821 clonal complex caused several serogroup C meningococcal outbreaks unexpectedly during 2003–2005 in China. We fabricated a whole-genome microarray of Chinese N. meningitidis serogroup C representative isolate 053442 and characterized 27 ST-4821 complex isolates which were isolated from different serogroups using comparative genomic hybridization (CGH) analysis. This paper provides important clues which are helpful to understand the genome composition and genetic background of different serogroups isolates, and possess significant meaning to the study of the newly emerged hyperinvasive lineage. Keywords: comparative genomic hybridization
Project description:Neisseria meningitidis is a major cause of bacterial meningitis and septicemia worldwide. Seven new serogroup C meningococci were isolated from two provinces of China in January, 2006. Their PorA VR types were P1.20, 9. Multilocus sequence typing results indicated that they all belonged to ST-7. It is a new serogroup C N. meningitidis sequence type clone identified in China. Here we also present the results of a genomic comparison of these isolates with other 15 N. meningitidis serogroup A and B isolates, which belonged to ST-7, based on comparative genomic hybridization analysis. The data described here would be helpful to monitor the spread of this new serogroup C meningococci sequence type clone in China and worldwide. Keywords: comparative genomic hybridization To compare the genome compositions of these menC ST-7 isolates with those of menC ST-4821 isolates, menA ST-7 isolates and menB ST-7 isolates, we performed comparative genomic hybridization (CGH) analysis among 17 N. meningitidis isolates (including two newly identified menC ST-7 isolates) using an updated version of the whole-genome microarray of N. meningitidis serogroup C isolate 053442 .
Project description:Neisseria meningitidis is the leading cause of bacterial meningitis and septicemia worldwide. The novel ST-4821 clonal complex caused several serogroup C meningococcal outbreaks unexpectedly during 2003â2005 in China. We fabricated a whole-genome microarray of Chinese N. meningitidis serogroup C representative isolate 053442 and characterized 27 ST-4821 complex isolates which were isolated from different serogroups using comparative genomic hybridization (CGH) analysis. This paper provides important clues which are helpful to understand the genome composition and genetic background of different serogroups isolates, and possess significant meaning to the study of the newly emerged hyperinvasive lineage. To further understand the genome diversity of ST-4821 complex isolates, CGH analysis was employed to compare the genomic content of 053442 with those of 27 ST-4821 complex isolates which were isolated from 14 provinces of China during 1977â2005.
Project description:Salmonella enterica serovar Typhimurium (S. Typhimurium) is a major cause of salmonellosis, with various multidrug-resistant pathovariants emerging. Here, we investigated a distinct rough colony variant with potentially enhanced environmental adaptation in China. Whole-genome sequencing of 2,212 Chinese isolates and 1,739 publicly available isolates revealed the population structure and evolutionary history of the rough colony variants. These variants showed macro, red, dry, and rough (mrdar) colonies with better biofilm-forming abilities at 28 °C and 37 °C compared to typical rdar colonies. The mrdar variants displayed expansive multidrug resistance, mainly attributed to an IncHI2 plasmid carrying 19 antimicrobial resistance genes. Phylogenomic analysis divided global collections into six lineages, with the majority of mrdar variants in sublineage L6.5, which originated from Chinese smooth colony strains and possibly emerged circa 1977. Upregulation of the csgDEFG operons was observed among mrdar variants, probably due to a distinct point mutation (-44G>T) in the csgD gene promoter. Pangenome and genome-wide association analyses identified 87 specific accessory genes and 72 distinct single nucleotide polymorphisms associated with the mrdar morphotype. This study presents the first large-scale, genome-based study of a distinct rdar colony morphology variant of S. Typhimurium in China, highlighting its global epidemic potential. Ongoing surveillance and genomic epidemiological studies are required to control epidemics, monitor bacterial population changes, and assess associated risks to global public health.
Project description:Salmonella Heidelberg is currently the 9th common serovar and has more than twice the average incidence of blood infections in Salmonella. A recent Salmonella Heidelberg outbreak in chicken infected 634 people during 2013-2014, with a hospitalization rate of 38% and an invasive illness rate of 15%. While the company’s history suggested longstanding sanitation issues, the strains’ characteristics which may have contributed to the outbreak are unknown. We hypothesized that the outbreak strains of S. Heidelberg might possess enhanced stress tolerance or virulence capabilities. Consequently, we obtained nine food isolates collected during the outbreak investigation and several reference isolates and tested their tolerance to processing stresses, their ability to form biofilms, and their invasiveness in vitro. We further performed RNA-sequencing on three isolates with varying heat tolerance to determine the mechanism behind our isolates’ enhanced heat tolerance. Ultimately, we determined that (i) many Salmonella Heidelberg isolates associated with a foodborne outbreak have enhanced heat resistance (ii) Salmonella Heidelberg outbreak isolates have enhanced biofilm-forming ability under stressful conditions, compared to the reference strain (iii) exposure to heat stress may also increase Salmonella Heidelberg isolates’ antibiotic resistance and virulence capabilities and (iv) Salmonella Heidelberg outbreak-associated isolates are primed to better survive stress and cause illness. This data helps explain the severity and scope of the outbreak these isolates are associated with and can be used to inform regulatory decisions on Salmonella in poultry and to develop assays to screen isolates for stress tolerance and likelihood of causing severe illness.
Project description:THP-1 Macrophages were infected with Mycobacterium tuberculosis clinical isolates from Xinjiang, China, and H37Rv for 24 hours, respectively, and their transcriptomes were sequenced to investigate the specific biological processes that occur after infection of macrophages with Mycobacterium tuberculosis clinical isolates from Xinjiang, China.
2025-08-23 | GSE275640 | GEO
Project description:Whole Genome Sequences of Shigella isolates
| PRJNA1104399 | ENA
Project description:Whole genome sequences for M.tuberculosis isolates
Project description:Yunnan Province, China is thought to be the original source of biovar Orientalis of Yersinia pestis, the causative agent of the third plague pandemic that has spread globally since the end of the 19th century. Although encompassing a large area of natural plague foci, Y. pestis strains have rarely been found in live rodents during surveillance in Yunnan, and most isolates are from rodent corpses and their fleas. In 2017, 10 Y. pestis strains were isolated from seven live rodents and three fleas in Heqing County (HQ) of Yunnan. These strains were supposed to have low virulence to local rodents Eothenomys miletus and Apodemus chevrieri because the rodents were healthy and no dead animals were found in surrounding areas, as had occurred in previous epizootic disease. We performed microscopic and biochemical examinations of the isolates,and compared their whole-genome sequences and transcriptome with those of 10 high virulence Y. pestis strains that were isolated from the adjacent city (Lijiang). We analyzed the phenotypic, genomic, and transcriptomic characteristics of live rodent isolates. The isolates formed a previously undefined monophyletic branch of Y. pestis that was named 1.IN5. Six SNPs, two indels, and one copy number variation were detected between live rodent isolates and the high virulence neighbors. No obvious functional consequence of these variations was found according to the known annotation information. Among the genes that were differentially expressed between the live rodent isolates and their high virulence neighbors, we detected five iron transfer-related genes that were significantly up-regulated in live rodent isolates compared with high virulence isolates (|log2 (FC) | >1, p.adjust <0.05), indicating these genes may be related to the low-virulence phenotype. The novel genotype of Y. pestis reported here provides further insights into the evolution and spread of plague as well as clues that may help to decipher the virulence mechanism of this notorious pathogen.