Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Mol Microbiol. 2011 Jul;81(2):554-70. doi: 10.1111/j.1365-2958.2011.07715.x. Epub 2011 Jun 16.

Vanadate and triclosan synergistically induce alginate production by Pseudomonas aeruginosa strain PAO1.

Author information

  • 1Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine at Marshall University, Huntington, WV 25755-9320, USA.

Abstract

Alginate overproduction by P. aeruginosa strains, also known as mucoidy, is associated with chronic lung infections in cystic fibrosis (CF). It is not clear how alginate induction occurs in the wild-type (wt) mucA strains. When grown on Pseudomonas isolation agar (PIA), P. aeruginosa strains PAO1 and PA14 are non-mucoid, producing minimal amounts of alginate. Here we report the addition of ammonium metavanadate (AMV), a phosphatase inhibitor, to PIA (PIA-AMV) induced mucoidy in both these laboratory strains and early lung colonizing non-mucoid isolates with a wt mucA. This phenotypic switch was reversible depending on the availability of vanadate salts and triclosan, a component of PIA. Alginate induction in PAO1 on PIA-AMV was correlated with increased proteolytic degradation of MucA, and required envelope proteases AlgW or MucP, and a two-component phosphate regulator, PhoP. Other changes included the addition of palmitate to lipid A, a phenotype also observed in chronic CF isolates. Proteomic analysis revealed the upregulation of stress chaperones, which was confirmed by increased expression of the chaperone/protease MucD. Altogether, these findings suggest a model of alginate induction and the PIA-AMV medium may be suitable for examining early lung colonization phenotypes in CF before the selection of the mucA mutants.

© 2011 Blackwell Publishing Ltd.

PMID:
21631603
[PubMed - indexed for MEDLINE]
PMCID:
PMC3134167
Free PMC Article

Images from this publication.See all images (6)Free text

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

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Blackwell Publishing Icon for PubMed Central
    Loading ...
    Write to the Help Desk