PURIFICATION AND CHARACTERIZATION OF A CELL-WALL ASSOCIATED PROTEINASE OF LACTOBACILLUS-HELVETICUS CP53

Citation
H. Ono et al., PURIFICATION AND CHARACTERIZATION OF A CELL-WALL ASSOCIATED PROTEINASE OF LACTOBACILLUS-HELVETICUS CP53, Milchwissenschaft, 52(7), 1997, pp. 373-377
Citations number
14
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Food Science & Tenology
Journal title
ISSN journal
0026-3788
Volume
52
Issue
7
Year of publication
1997
Pages
373 - 377
Database
ISI
SICI code
0026-3788(1997)52:7<373:PACOAC>2.0.ZU;2-#
Abstract
An extracellular proteinase was purified from Lactobacillus helveticus CP53 cells to homogeneity by DEAE ion exchange chromatography followe d by casein-sepharose. The molecular mass of this enzyme was estimated to be 170,000 by SDS-7%PAGE. The enzyme had a maximum activity at pH 6.5 and 42 degrees C, and the activity was completely inhibited by the addition of phenyl methane sulfonyl fluoride. (PMSF). From the compar ative study of the proteinase in the specificity towards beta-casein, some differences were observed in the hydrolyzation pattern between L. helveticus CP53 and other strains. Significant difference was observe d in the specificity of the enzymes towards a beta-casein peptide, Ser -Trp-Met-His-Gln-Pro-His. The degradation product of a synthetic pepti de of alpha(s1)-casein fragment (1 to 23) by the proteinase of CP53 wa s also different from that of other strains. These results suggested t hat the proteinase of L. helveticus CP53 is a different type of enzyme from those identified so far among the L. helveticus proteinases.