Complete Genome Sequences of Leclercia sp. W6 and W17 Isolated from a Gastric Cancer Patient.

Leclercia sp. W6 and W17, which belong to the Enterobacteriaceae, were isolated from a stomach sample from a 78-year-old female gastric cancer patient, and genomic sequencing and analysis were performed. The genome of Leclercia sp. W6 consists of one chromosome with a size of 4,945,486 bp, while that of Leclercia sp. W17 contains one chromosome and two plasmids with a total size of 5,125,645 bp. Average nucleotide identity (ANI) calculations indicated that strains W6 and W17 exhibited similarities < 91.0% to other strains within the Enterobacteriaceae, except for six Leclercia strains. Phylogenomic analysis based on core-genome showed that strains W6 and W17 belong to the genus Leclercia, and phylogenetic analysis based on ANI values revealed that strains W6 and W17 formed an independent clade from those six Leclercia strains. Furthermore, comparative genomic analysis revealed that strains W6 and W17 had 5086 orthologous clusters (OCs) in their pan-genomes, and 59 exclusive OCs which were absent in their closest relatives. Genomic annotations revealed that the genomes of strains W6 and W17 encoded genes related to multidrug resistance clusters, multiple antibiotic resistance loci, and multidrug efflux pumps and had an identical urease gene cluster and a dissimilatory nitrate reduction pathway. Bioinformatic analyses indicated that strains W6 and W17 represented a novel species within the genus Leclercia. Genomic annotations revealed that these strains encoded genes related to multidrug resistance, nitrate reduction, and urease activity, which contribute to gastric malignant transformation. This will broaden our knowledge of the genetic mechanisms of the Enterobacteriaceae and help improve the clinical conditions of gastric cancer patients.

Isolation and characterization of a crude oil degrading bacteria from formation water: comparative genomic analysis of environmental Ochrobactrum intermedium isolate versus clinical strains.

In this study, we isolated an environmental clone of Ochrobactrum intermedium, strain 2745-2, from the formation water of Changqing oilfield in Shanxi, China, which can degrade crude oil. Strain 2745-2 is aerobic and rod-shaped with optimum growth at 42 °C and pH 5.5. We sequenced the genome and found a single chromosome of 4 800 175 bp, with a G+C content of 57.63%. Sixty RNAs and 4737 protein-coding genes were identified: many of the genes are responsible for the degradation, emulsification, and metabolizing of crude oil. A comparative genomic analysis with related clinical strains (M86, 229E, and LMG3301(T)) showed that genes involved in virulence, disease, defense, phages, prophages, transposable elements, plasmids, and antibiotic resistance are also present in strain 2745-2.