Novel large-scale chromosomal transfer in Bacteroides fragilis contributes to its pan-genome and rapid environmental adaptation

Fasahath Husain, Kevin Tang, Yaligara Veeranagouda, Renata Boente, Sheila Patrick, Garry Blakely, Hannah M Wexler

Research output: Contribution to journalArticlepeer-review

11 Citations (Scopus)
211 Downloads (Pure)

Abstract

Bacteroides fragilis, an important component of the human gastrointestinal microbiota, can cause lethal extra-intestinal infection upon escape from the gastrointestinal tract. We demonstrated transfer and recombination of large chromosomal segments from B. fragilis HMW615, a multidrug resistant clinical isolate, to B. fragilis 638R. In one example, the transfer of a segment of ~435 Kb/356 genes replaced ~413 Kb/326 genes of the B. fragilis 638R chromosome. In addition to transfer of antibiotic resistance genes, these transfers (1) replaced complete divergent polysaccharide biosynthesis loci; (2) replaced DNA inversion-controlled intergenic shufflons (that control expression of genes encoding starch utilization system outer membrane proteins) with more complex, divergent shufflons; and (3) introduced additional intergenic shufflons encoding divergent Type 1 restriction/modification systems. Conjugative transposon-like genes within a transferred segment and within a putative integrative conjugative element (ICE5) ~45 kb downstream from the transferred segment both encode proteins that may be involved in the observed transfer. These data indicate that chromosomal transfer is a driver of antigenic diversity and nutrient adaptation in Bacteroides that (1) contributes to the dissemination of the extensive B. fragilis pan-genome, (2) allows rapid adaptation to a changing environment and (3) can confer pathogenic characteristics to host symbionts.
Original languageEnglish
JournalMicrobial Genomics
Volume2017
Issue number3
Early online date14 Nov 2017
DOIs
Publication statusEarly online date - 14 Nov 2017

Fingerprint

Dive into the research topics of 'Novel large-scale chromosomal transfer in Bacteroides fragilis contributes to its pan-genome and rapid environmental adaptation'. Together they form a unique fingerprint.

Cite this