In uropathogenetic E coli strains, adhesins enable the anchorage

In uropathogenetic E. coli strains, adhesins enable the anchorage to urinary tract to overcome the hydrodynamics of micturition, even though E. coli cannot live solely on citrate in anaerobic condition [2]. Other factors in the K. pneumoniae selleck kinase inhibitor genome likely also contribute to urinary infection. To investigate the host-microbial

interaction in UTI and to overcome the complex clinical situations, animal models will be necessary for determining the role of this 13-kb genomic island in K. pneumoniae in colonizing the urinary tract. Genomic diversity on citrate fermentation The genes associated with citrate fermentation are different in composition and order in the sequenced Enterobacteriaceae genomes (Figure 1). In Salmonella enterica serovar Typhimurium LT2 (GenBank: AE006468), which is capable of citrate fermentation using the

same pathway, two gene clusters similar to the 13-kb region are present in the genome (Figure 1b). One of BAY 11-7082 supplier them (locus I) showing similar gene arrangement (citAB, and divergent citCDEFXGT) was identified between the rna RNase I gene (Locus_tag: STM0617, location: 679989-680795) and the dcuC C4-dicarboxylate transporter gene (Locus_tag: STM0627, location: 690391-691776) in the LT2 genome. The other (locus II) (citS-oadGAB-citAB, and divergent citC2D2E2F2X2G2) was found between rihC putative nucleotide hydrolase gene (Locus_tag: STM0051, location: 60164-61084) and dapB (Locus_tag: STM0064, location: 74017-74838). Both loci in LT2 carry the citX gene in respect to that of the 13-kb island of K. pneumoniae. Based on the composition of the gene clusters and the genes at the vicinity, it appears that the second copy (locus II) from LT2 is more related (closer) to

the 13-kb island of K. pneumoniae, albeit three hypothetical orfs (Figure 1a) next to the citB in K. pneumoniae are MI-503 molecular weight missing in LT2. The first copy of the gene cluster from LT2, as shown in Figure 1b, is similar in gene organization to the citrate fermentation gene cluster in E. coli K12 (GenBank: U00096), which contains a citAB and a divergent citCDEFXGT positioned next to the rna RNase I gene (Locus_tag: b0611, location: 643420-644226) (Figure 1c). The citT encodes a citrate-succinate antiporter for citrate uptake in E. coli [19]. While the citrate fermentation genes corresponding to locus I is missing in K. pneumoniae, homologs of the rna and dcuC identified at the two ends of this gene cluster were juxtaposed to each other in the K. pneumoniae NTUH-K2044 (KP1607 and KP1608, location: 1551149-1553412), MGH 78578 (location: 742196-744459) and 342 (location: 2962203-3964466). On the other hand, homologs of the rihC and dapB, the genes flanking the two ends of the 13-kb genomic island from K. pneumoniae, were found adjacent to each other in the E. coli K12 genome (Locus_tag: b0030 and b0031, location: 27293-29295).

Comments are closed.