Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
50
pubmed:dateCreated
2009-12-7
pubmed:abstractText
Clostridium difficile is a major and growing problem as a hospital-associated infection that can cause severe, recurrent diarrhea. The mechanism by which the bacterium colonizes the gut during infection is poorly understood but undoubtedly involves protein components within the surface layer (S-layer), which play a role in adhesion. In C. difficile, the S-layer is composed of two principal components, the high and low molecular weight S-layer proteins, which are formed from the post-translational cleavage of a single precursor, SlpA. In the present study, we demonstrate that a recently characterized cysteine protease, Cwp84 plays a role in maturation of SlpA. Using a gene knock-out approach, we show that inactivation of the Cwp84 gene in C. difficile 630DeltaErm results in a bacterial phenotype in which only immature, single chain SlpA comprises the S-layer. The Cwp84 knock-out mutants (CDDeltaCwp84) displayed significantly different colony morphology compared with the wild-type strain and grew more slowly in liquid medium. SlpA extracted from CDDeltaCwp84 was readily cleaved into its mature subunits by trypsin treatment. Addition of trypsin to the growth medium also cleaved SlpA on CDDeltaCwp84 and increased the growth rate of the bacterium in a dose-dependent manner. Using the hamster model for C. difficile infection, CDDeltaCwp84 was found to be competent at causing disease with a similar pathology to the wild-type strain. The data show that whereas Cwp84 plays a role in the cleavage of SlpA, it is not an essential virulence factor and that bacteria expressing immature SlpA are able to cause disease.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1083-351X
pubmed:author
pubmed:issnType
Electronic
pubmed:day
11
pubmed:volume
284
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
34666-73
pubmed:dateRevised
2010-12-14
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Cwp84, a surface-associated cysteine protease, plays a role in the maturation of the surface layer of Clostridium difficile.
pubmed:affiliation
Research Department, Health Protection Agency, Porton Down, Salisbury, Wiltshire SP4 0JG, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't