English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Isolation of bacterial small colony variants (SCVs) from clinical specimens is not uncommon and can fundamentally change the outcome of the associated infections. Bacterial SCVs often emerge with their normal colony phenotype (NCV) co-isolates in the same sample. The basis of SCV emergence in vivo is not well understood in Gram-negative bacteria. In this study, we interrogated the causal genetic lesions of SCV growth in three pairs of NCV and SCV co-isolates of  Escherichia coli ,  Citrobacter freundii , and  Enterobacter hormaechei . We confirmed SCV emergence was attributed to limited genomic mutations: 4 single nucleotide variants in the  E. coli  SCV, 5 in  C. freundii , and 8 in  E. hormaechei . In addition, a 10.2 kb chromosomal segment containing 11 genes was deleted in the  E. hormaechei  SCV isolate. Each SCV had at least one coding change in a gene associated with bacterial oxidative respiration and another involved in iron capture. Chemical and genetic rescue confirmed defects in heme biosynthesis for  E. coli  and  C. freundii  and lipoic acid biosynthesis in  E. hormaachei  were responsible for the SCV phenotype. Prototrophic growth in all 3 SCV  Enterobacteriaceae  species was unaffected under anaerobic culture conditions in vitro, illustrating how SCVs may persist in vivo.

Inactivation of genes in oxidative respiration and iron acquisition pathways in pediatric clinical isolates of Small colony variant Enterobacteriaceae