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PubMed · 7694658

Multiple interactions between human vitronectin and Staphylococcus aureus.

O D Liang·M Maccarana·J I Flock·M Paulsson·K T Preissner·T Wadström
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Abstract

Multiple interactions between human vitronectin and Staphylococcus aureus strain V8 were observed. An upward-curved Scatchard plot indicated both high-affinity binding (Kd1 = 7.4 x 10(-10) M) with 260 binding sites per bacterial cell and moderate-affinity binding (Kd2 = 7.4 x 10(-8) M) with 5240 copies per cell. Negative cooperativity of this binding was characterized by its Hill coefficient of less than unity (0.70 +/- 0.08). Up to 60% of the vitronectin-bacteria interaction was unaffected by high ionic strength (i.e., 2.4 M NaCl), and was not inhibited by highly-charged heparin oligosaccharides. Various oligosaccharides (4-20 monosaccharide units) generated by partial deaminative cleavage of heparin were found to affect vitronectin binding to S. aureus. Short-chain-length oligosaccharides increase and long oligosaccharides inhibit vitronectin binding, in accordance with direct association of these saccharides with multimeric vitronectin. A protein having a molecular mass of 60 kDa was identified as a putative high-affinity staphylococcal vitronectin-binding protein. These results indicate that interaction of multimeric vitronectin, mostly present at extracellular matrix sites with multiple recognition sites on the S. aureus surface, may contribute to bacterial colonisation.

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Binding SitesBlotting, WesternGlycoproteinsHumansOligosaccharidesOsmolar ConcentrationStaphylococcus aureusVitronectinJournal ArticleResearch Support, Non-U.S. Gov't

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O D Liang, M Maccarana, J I Flock, M Paulsson, K T Preissner, T Wadström. 1993-11-25. Multiple interactions between human vitronectin and Staphylococcus aureus.. https://doi.org/10.1016/0925-4439(93)90122-h

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