Enzymatic properties of a novel thermostable, thermophilic, alkaline and chelator resistant amylase from an alkaliphilic Bacillus sp. isolate ANT-6

Burhan A., Nisa U., Gökhan C., Ömer C., Ashabil A., Osman G.

Process Biochemistry, vol.38, no.10, pp.1397-1403, 2003 (SCI-Expanded, Scopus)

  • Publication Type: Article / Article
  • Volume: 38 Issue: 10
  • Publication Date: 2003
  • Doi Number: 10.1016/s0032-9592(03)00037-2
  • Journal Name: Process Biochemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1397-1403
  • Keywords: Alkaliphilic, Bacillus sp., Chelator resistant, Thermophile, Thermostable, α-Amylase
  • Hatay Mustafa Kemal University Affiliated: Yes

Abstract

A thermostable alkaline α-amylase producing Bacillus sp. ANT-6 was isolated from soil samples. Enzyme synthesis occurred at temperatures between 25 and 45°C with an optimum of 37°C. There was a slight variation in amylase synthesis within the pH range 7 and 11 with an optimum pH of 9. The optimum temperatures for amylase production and growth were the same. Analyses of the enzyme by sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed a single band, which show amylolytic activity, detected in starch-gel. The relative molecular mass of the partial purified enzyme was estimated to be 94 500 Da. The enzyme showed optimum activity at pH 10.5 and 80°C. The partial purified enzyme was highly active in the alkaline range of pH (9.5-13), and it was completely active up to 100°C retaining 85.5% initial activity at pH 10.5. Enzyme activity was enhanced in the presence of 5 mM CaCl2 (110%) and 3 mM PMSF (103%), and inhibition with 5 mM by Zn, Na, Na-sulphide, EDTA (10 mM), Urea (8 M) and SDS (0.1%) was obtained 36.9, 21.5, 22.2, 4.90, 86% and 10.27, respectively. The enzyme was stable (55%) at high alkaline pH for 24 h. So our result showed that the enzyme was both alkaline, thermostable, thermopile and chelator resistant. The ANT-6 amylase enzyme may be suitable in liquefaction of starch, in detergent and textile industries and in other industrial applications. © 2003 Elsevier Science Ltd. All rights reserved.