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Anéas,M.A.F.; Portaro,F.C.V.; Lebrun,I.; Juliano,L.; Palma,M.S.; Fernandes,B.L.. |
The opportunistic bacterium Proteus mirabilis secretes a metalloprotease, ZapA, considered to be one of its virulence factors due to its IgA-degrading activity. However, the substrate specificity of this enzyme has not yet been fully characterized. In the present study we used fluorescent peptides derived from bioactive peptides and the oxidized ß-chain of insulin to determine the enzyme specificity. The bradykinin- and dynorphin-derived peptides were cleaved at the single bonds Phe-Ser and Phe-Leu, with catalytic efficiencies of 291 and 13 mM/s, respectively. Besides confirming already published cleavage sites, a novel cleavage site was determined for the ß-chain of insulin (Val-Asn). Both the natural and the recombinant enzyme displayed the same broad... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Proteus mirabilis; Metalloprotease; Substrate specificity; Fluorogenic peptides; IgA; Insulin ß-chain. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001001100004 |
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