Amylase of the thermophilic actinomycete Thermomonospora vulgaris

✍ Scribed by Prof. Dr. A. M. Allam; A. M. Hussein; A. M. Ragab

• Book ID: 102390367
• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 316 KB
• Volume: 15
• Category: Article
• ISSN: 0233-111X
• DOI: 10.1002/jobm.19750150602

✦ Synopsis

Abstract

α‐Amylase of the thermophilic actinomycete Thermomonospora vulgaris was partially purified. Maximal enzyme activity was obtained at 60 °C and pH 6.0. K~M~ value was 1.4%. The effect of some metal salts on enzyme activity was studied. Enzyme activity was inhibited by KCN, EDTA, and iodoacetate. Inhibition by EDTA was completely nullified by CaCl~2~, but the inhibition by iodoacetate was not overcome by 2‐mercaptoethanol. Exposure of the enzyme to pH 7.0 and 9.0 for 2hr. did not affect the enzyme, but exposure to pH 3.0 for few minutes completely inactivated the enzyme. Exposure of the enzyme to 60 °C resulted in an appreciable inactivation and exposure to 80 °C completely inactivated the enzyme. Addition of CaCl~2~, 2‐mercaptoethanol, or enzyme substrate did not stabilize the 60 °C exposed enzyme. However, bovine serum albumin had a protective effect when the enzyme was exposed to 60 °C but not to 80 °C. The enzyme was stable in the presence of 8 M urea.