Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2004-1-6
pubmed:abstractText
Alpha-defensins are peptides secreted by polymorphonuclear cells and provide antimicrobial protection mediated by disruption of the integrity of bacterial cell walls. Staphylokinase is an exoprotein produced by Staphylococcus aureus, which activates host plasminogen. In this study, we analyzed the impact of interaction between alpha-defensins and staphylokinase on staphylococcal growth. We observed that staphylokinase induced extracellular release of alpha-defensins from polymorphonuclear cells. Moreover, a direct binding between alpha-defensins and staphylokinase was shown to result in a complex formation. The biological consequence of this interaction was an almost complete inhibition of the bactericidal effect of alpha-defensins. Notably, staphylokinase with blocked plasminogen binding site still retained its ability to neutralize the bactericidal effect of alpha-defensins. In contrast, a single mutation of a staphylokinase molecule at position 74, substituting lysine for alanine, resulted in a 50% reduction of its alpha-defensin-neutralizing properties. The bactericidal properties of alpha-defensins were tested in 19 S. aureus strains in vitro and in a murine model of S. aureus arthritis. Staphylococcal strains producing staphylokinase were protected against the bactericidal effect of alpha-defensins. When staphylokinase was added to staphylokinase-negative S. aureus cultures, it almost totally abrogated the effect of alpha-defensins. Finally, human neutrophil peptide 2 injected intra-articularly along with bacteria alleviated joint destruction. In this study, we report a new property of staphylokinase, its ability to induce secretion of defensins, to complex bind them and to neutralize their bactericidal effect. Staphylokinase production may therefore be responsible in vivo for defensin resistance during S. aureus infections.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
172
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1169-76
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:14707093-Adult, pubmed-meshheading:14707093-Aged, pubmed-meshheading:14707093-Aged, 80 and over, pubmed-meshheading:14707093-Animals, pubmed-meshheading:14707093-Arthritis, Experimental, pubmed-meshheading:14707093-Enzyme Activation, pubmed-meshheading:14707093-Female, pubmed-meshheading:14707093-Humans, pubmed-meshheading:14707093-Immunity, Innate, pubmed-meshheading:14707093-Male, pubmed-meshheading:14707093-Metalloendopeptidases, pubmed-meshheading:14707093-Mice, pubmed-meshheading:14707093-Microbial Sensitivity Tests, pubmed-meshheading:14707093-Middle Aged, pubmed-meshheading:14707093-Nasal Mucosa, pubmed-meshheading:14707093-Neutrophils, pubmed-meshheading:14707093-Plasminogen, pubmed-meshheading:14707093-Recombinant Proteins, pubmed-meshheading:14707093-Staphylococcal Infections, pubmed-meshheading:14707093-Staphylococcus aureus, pubmed-meshheading:14707093-alpha-Defensins
pubmed:year
2004
pubmed:articleTitle
Staphylococcus aureus resists human defensins by production of staphylokinase, a novel bacterial evasion mechanism.
pubmed:affiliation
Department of Rheumatology and Inflammation Research, Sahlgrenska University Hospital, Guldhedsgatan 10, S-413 46 Göteborg, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't