Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2005-3-8
pubmed:abstractText
Because of its biofilm forming potential Staphylococcus epidermidis has evolved as a leading cause of device-related infections. The polysaccharide intercellular adhesin (PIA) is significantly involved in biofilm accumulation. However, infections because of PIA-negative strains are not uncommon, suggesting the existence of PIA-independent biofilm accumulation mechanisms. Here we found that biofilm formation in the clinically significant S. epidermidis 5179 depended on the expression of a truncated 140 kDa isoform of the 220 kDa accumulation-associated protein Aap. As expression of the truncated Aap isoform leads to biofilm formation in aap-negative S. epidermidis 1585, this domain mediates intercellular adhesion in a polysaccharide-independent manner. In contrast, expression of full-length Aap did not lead to a biofilm-positive phenotype. Obviously, to gain adhesive function, full-length Aap has to be proteolytically processed through staphylococcal proteases as demonstrated by inhibition of biofilm formation by alpha(2)-macroglobulin. Importantly, also exogenously added granulocyte proteases activated Aap, thereby inducing biofilm formation in S. epidermidis 5179 and four additional, independent clinical S. epidermidis strains. It is therefore reasonable to assume that in vivo effector mechanisms of the innate immunity can directly induce protein-dependent S. epidermidis cell aggregation and biofilm formation, thereby enabling the pathogen to evade clearance by phagocytes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
55
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1883-95
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Induction of Staphylococcus epidermidis biofilm formation via proteolytic processing of the accumulation-associated protein by staphylococcal and host proteases.
pubmed:affiliation
Institut für Infektionsmedizin, Universitätsklinikum Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany. rohde@uke.uni-hamburg.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't