Factor XIIIa mediated attachment of S. aureus fibronectin-binding protein A (FnbA) to fibrin: identification of Gln103 as a major cross-linking site.

摘要: In the present study we investigated role of factor XIIIa reactive Gln and Lys sites staphylococcal FnbA receptor in cross-linking reaction with R chains fibrin. For this purpose produced two recombinant mutants which either a single Gln103 site (1Q FnbA) or all identified Gln103, 105, 783, 830 Lys157, 503, 620, 762 (4Q4K were substituted Ala residues. The results FXIIIa-catalyzed incorporation dansylcadaverine dansylated peptide patterned on NH2-terminal segment fibronectin revealed that reactivity substrate was drastically reduced 1Q 4Q4K mutants, while only moderately decreased FnbA. When it tested FXIIIa-mediated fibrin reaction, mutant exhibited about 70-85% reduction compared to wild-type These demonstrate participates predominantly via its site. Several minor sites, including residues replaced mutant, contributed an additional 15-30% total Comparison amino acid sequences follow major several known proteins FXIIIa displays preference for glutamine residue x QAxBxPx sequence, where Q represents glutamine, is any residue, A polar B valine leucine, P proline.