ID 112326
Title Alternative
OMV Production in Bacteroides fragilis
Author
Nakayama-Imaohji, Haruyuki Kagawa University
Yamasaki, Hisashi Wakayama Medical University
Yoneda, Saori Kagawa University
Nariya, Hirofumi Kagawa University
Suzuki, Motoo Kagawa University
Secher, Thomas Inserm UMR1043|INRA USC 1360|CNRS UMR5282|Université de Toulouse
Oswald, Eric Inserm UMR1043|INRA USC 1360|CNRS UMR5282|Université de Toulouse|Hôpital Purpan
Hayashi, Tetsuya Kyushu University
Kuwahara, Tomomi Kagawa University
Content Type
Journal Article
Description
Phase changes in Bacteroides fragilis, a member of the human colonic microbiota, mediate variations in a vast array of cell surface molecules, such as capsular polysaccharides and outer membrane proteins through DNA inversion. The results of the present study show that outer membrane vesicle (OMV) formation in this anaerobe is also controlled by DNA inversions at two distantly localized promoters, IVp-I and IVp-II that are associated with extracellular polysaccharide biosynthesis and the expression of outer membrane proteins. These promoter inversions are mediated by a single tyrosine recombinase encoded by BF2766 (orthologous to tsr19 in strain NCTC9343) in B. fragilis YCH46, which is located near IVp-I. A series of BF2766 mutants were constructed in which the two promoters were locked in different configurations (IVp-I/IVp-II = ON/ON, OFF/OFF, ON/OFF or OFF/ON). ON/ON B. fragilis mutants exhibited hypervesiculating, whereas the other mutants formed only a trace amount of OMVs. The hypervesiculating ON/ON mutants showed higher resistance to treatment with bile, LL-37, and human β-defensin 2. Incubation of wild-type cells with 5% bile increased the population of cells with the ON/ON genotype. These results indicate that B. fragilis regulates the formation of OMVs through DNA inversions at two distantly related promoter regions in response to membrane stress, although the mechanism underlying the interplay between the two regions controlled by the invertible promoters remains unknown.
Journal Title
PLOS ONE
ISSN
19326203
Publisher
PLOS
Volume
11
Issue
2
Start Page
e0148887
Published Date
2016-02-09
Rights
Copyright: © 2016 Nakayama-Imaohji et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
EDB ID
DOI (Published Version)
URL ( Publisher's Version )
FullText File
language
eng
TextVersion
Publisher
departments
Oral Sciences