title: Characterization and chillproofing activity of two enzymes from Streptomyces species.
abstract: Two enzymes, amylase and protease of Streptomyces species were purified by a combination of ion exchange chromatography and gel filtration and characterized. The amylase had an exoaction on starch yielding maltose as a major end product and was identified as beta-amylase. The purified amylase had a molecular weight of 48,000 and was maximally active at 35 degrees C and at pH 6.0. On the other hand, protease had a molecular weight of 21,000 and was most active at pH 10.0 and at a temperature of 30 degrees C. The Km or MICHAELIS constant of amylase for maize starch was 0.333 mg/ml while that of protease for casein was 2.5 mg/ml. The feasibility of using the purified protease for various industrial application especially in the chillproofing of beer is discussed.
authors.affiliation: Department of Biological Sciences, University of Calabar, Nigeria.
authors.forename: C A
authors.initials: CA
authors.lastname: Etok
authors.forename: O U
authors.initials: OU
authors.lastname: Eka
mesh_terms: D001515:Beer; D010450:Endopeptidases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007218:Industrial Microbiology; D008970:Molecular Weight; D013302:Streptomyces / Q000201:enzymology*; D013696:Temperature; D001614:beta-Amylase / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D001614:beta-Amylase; D010450:Endopeptidases