Caracterización de Aminopeptidasa N de Streptococcus thermophilus TW43

EMILIO MARGUET; MARISOL VALLEJO; MICAELA PESCUMA

REVISTA DE CIENCIA Y TECNOLOGíA

Facultad de Ciencias Exactas, Químicas y Naturales, UNaM

Lugar: Posadas; Año: 2006 p. 12 - 17

0329-8922

Biochemical and kinetic characteristics of the general Aminopeptidase N (PepN) from Streptococcus thermophilus TW43 were studied. Maximal activity of the enzyme was determined at pH 6.8 and 40ºC. Pep N was strongly inhibited by EDTA and o-phenanthroline. Therefore, it was considered to be a metallopeptidase. Imidazole partially inhibited enzyme activity suggesting histidine is one of the amino acids related to metal binding in the active site. Among the bivalent cations only Cu++ exhibited slight inhibition while Co++ increased enzymatic activity nearly fivefold. PepN remained active under ripening condition (pH 5.0 and 15ºC) suggesting that Streptococcus thermophilus TW43 may contribute to flavor cheese development through its role in production of free amino acids.