Comparative catalytic activity of two plant proteinases upon caprine caseins in solution

• Autor(a) principal: Silva, Sofia V.
• Data de Publicação: 2000
• Outros Autores: Malcata, F. Xavier
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.14/6819
• topic: Goat; Rennet substitute; Proteolysis; Electrophoresis; RP-HPLC

The proteolytic activities of cardosins A and B, two (plant) proteinases from Cynara cardunculus, toward caprine caseins, independently, or in the presence of each other as Na-caseinate, were studied in a comparative fashion using polyacrylamide gel electrophoresis and reversed phase high performance liquid chromatography. The electrophoretic degradation patterns of both αs- and β-casein, brought about by the cardosins, were similar to one another. In what concerns the specificity of these two enzymes upon caseinate, the major cleavage sites were Leu127-Thr128 and Leu190-Tyr191, both in β-casein. When caseins were tested independently, both cardosins cleaved Phe153-Tyr154 in αs1-casein, as well as Leu127-Thr128 and Leu190-Tyr191 in β-casein.