Project description:Background Compelling evidence indicates that Shigella species, the etiologic agents of bacillary dysentery, as well as enteroinvasive Escherichia coli, are derived from multiple origins of Escherichia coli and form a single pathovar. To further understand the genome diversity and virulence evolution of Shigella, comparative genomic hybridization microarray analysis was employed to compare the gene content of E. coli K-12 with those of 43 Shigella strains from all serotypes. Results For the 43 strains subjected to CGH microarray analyses, the common backbone of the Shigella genome was estimated to contain more than 1,900 open reading frames, with a mean number of 729 undetectable ORFs. The mosaic distribution of absent regions indicated that insertions and/or deletions have led to the highly diversified genomes of pathogenic strains. Conclusion These results support the hypothesis that by gain and loss of functions, Shigella species became successful human pathogens through convergent evolution from diverse genomic backgrounds. Moreover, we also found many specific differences between different lineages, providing a window into understanding bacterial speciation and taxonomic relationships. Keywords: comparative genomic hybridization
Project description:Investigation of whole genome gene expression level changes in a Escherichia coli MG1655 K-12 ∆fnr mutant, compared to the wild-type strain. The mutations engineered into this strain produce a strain lacking the FNR protein.
Project description:To investigate the regulatory targets of the RegR virulence regulon of rabbit specific enteropathogenic Escherichia coli strain E22
Project description:The genome-wide analysis was carried out to find out the genes responsible for single and multiple stress in Shigella flexneri 2a str. 2457T. E. coli used as a reference strain. This is RNA-seq data of E.coli K-12 MG1655.
Project description:The purpose of this study is to determine whether the presence of pathogenic Escherichia coli in colon is associated with psychiatric disorders.
Project description:The invasive bacteria recognition by host cells through autophagy is a key factor for determining bacterial infection. Enteroinvasive Escherichia coli (EIEC) express a protein IcsB, which in Shigella, is known for inactivating the bacterial degradation process. Once EIEC showed less expression of icsB when compared to S. flexneri, we proposed to investigate the autophagy caused by EIEC infection. Our results showed that IcsB protein is an important virulence factor in EIEC because it causes a camouflage of the bacteria in the eukaryotic cell. When there is low or none expression of the protein, the cell recognition of the invasive bacteria is high, decreasing the bacteria dissemination. This found confirms the importance of the gene transcription and the sequence, since the strain E. coli SM124/13, complemented with icsB from Shigella, showed higher dissemination efficiency inside of the host cell. Additionally, our results revealed that eukaryotic cell infected by EIEC or Shigella flexneri showed distinguish responses. In EIEC infection, the autophagy was activated in human cells, but not in a conventional mode. Our hypothesis is that EIEC is recognized by autophagy, being an important cell process for bacterial recognition.
Project description:The invasive bacteria recognition by host cells through autophagy is a key factor for determining bacterial infection. Enteroinvasive Escherichia coli (EIEC) express a protein IcsB, which in Shigella, is known for inactivating the bacterial degradation process. Once EIEC showed less expression of icsB when compared to S. flexneri, we proposed to investigate the autophagy caused by EIEC infection. Our results showed that IcsB protein is an important virulence factor in EIEC because it causes a camouflage of the bacteria in the eukaryotic cell. When there is low or none expression of the protein, the cell recognition of the invasive bacteria is high, decreasing the bacteria dissemination. This found confirms the importance of the gene transcription and the sequence, since the strain E. coli SM124/13, complemented with icsB from Shigella, showed higher dissemination efficiency inside of the host cell. Additionally, our results revealed that eukaryotic cell infected by EIEC or Shigella flexneri showed distinguish responses. In EIEC infection, the autophagy was activated in human cells, but not in a conventional mode. Our hypothesis is that EIEC is recognized by autophagy, being an important cell process for bacterial recognition.
Project description:The invasive bacteria recognition by host cells through autophagy is a key factor for determining bacterial infection. Enteroinvasive Escherichia coli (EIEC) express a protein IcsB, which in Shigella, is known for inactivating the bacterial degradation process. Once EIEC showed less expression of icsB when compared to S. flexneri, we proposed to investigate the autophagy caused by EIEC infection. Our results showed that IcsB protein is an important virulence factor in EIEC because it causes a camouflage of the bacteria in the eukaryotic cell. When there is low or none expression of the protein, the cell recognition of the invasive bacteria is high, decreasing the bacteria dissemination. This found confirms the importance of the gene transcription and the sequence, since the strain E. coli SM124/13, complemented with icsB from Shigella, showed higher dissemination efficiency inside of the host cell. Additionally, our results revealed that eukaryotic cell infected by EIEC or Shigella flexneri showed distinguish responses. In EIEC infection, the autophagy was activated in human cells, but not in a conventional mode. Our hypothesis is that EIEC is recognized by autophagy, being an important cell process for bacterial recognition.
