Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
PLoS Pathog. 2012 Feb;8(2):e1002532. doi: 10.1371/journal.ppat.1002532. Epub 2012 Feb 16.

Borrelia burgdorferi requires the alternative sigma factor RpoS for dissemination within the vector during tick-to-mammal transmission.

Author information

  • 1Department of Medicine, University of Connecticut Health Center, Farmington, Connecticut, United States of America.

Abstract

While the roles of rpoS(Bb) and RpoS-dependent genes have been studied extensively within the mammal, the contribution of the RpoS regulon to the tick-phase of the Borrelia burgdorferi enzootic cycle has not been examined. Herein, we demonstrate that RpoS-dependent gene expression is prerequisite for the transmission of spirochetes by feeding nymphs. RpoS-deficient organisms are confined to the midgut lumen where they transform into an unusual morphotype (round bodies) during the later stages of the blood meal. We show that round body formation is rapidly reversible, and in vitro appears to be attributable, in part, to reduced levels of Coenzyme A disulfide reductase, which among other functions, provides NAD+ for glycolysis. Our data suggest that spirochetes default to an RpoS-independent program for round body formation upon sensing that the energetics for transmission are unfavorable.

PMID:
22359504
[PubMed - indexed for MEDLINE]
PMCID:
PMC3280991
Free PMC Article

Images from this publication.See all images (8)Free text

Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Public Library of Science Icon for PubMed Central
    Loading ...
    Write to the Help Desk