HIGHLY THERMOSTABLE AND ALKALINE alpha-AMYLASE FROM A HALOTOLERANT-ALKALIPHILIC BACILLUS SP AB68

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Aygan A., ARIKAN B., Korkmaz H., DİNÇER S., ÇOLAK Ö.

BRAZILIAN JOURNAL OF MICROBIOLOGY, vol.39, no.3, pp.547-553, 2008 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 39 Issue: 3
  • Publication Date: 2008
  • Doi Number: 10.1590/s1517-83822008000300027
  • Journal Name: BRAZILIAN JOURNAL OF MICROBIOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.547-553
  • Keywords: Bacillus sp., alpha-amylase, Alkaliphilic, Thermostable, Enzyme, ENZYMATIC-PROPERTIES, PURIFICATION, ENZYMES, EXPRESSION, DIVERSITY, STRAIN
  • Çukurova University Affiliated: Yes

Abstract

An alkaliphilic and highly thermostable alpha-amylase producing Bacillus sp. was isolated from Van soda lake. Enzyme synthesis occurred at temperatures between 25 degrees C and 40 degrees C. Analysis of the enzyme by SDS-PAGE revealed a single band which was estimated to be 66 kDa. The enzyme was active in a broad temperature range, between 20 degrees C and 90 degrees C, with an optimum at 50 degrees C; and maximum activity was at pH 10.5. The enzyme was almost completely stable up to 80 degrees C with a remaining activity over 90% after 30 min pre-incubation. Thermostability was not increased in the presence of Ca2+. An average of 75% and 60 degrees C of remaining activity was observed when the enzyme was incubated between pH 5 and 9 for 1 h and for 2 h, respectively. The activity of the enzyme was inhibited by SDS and EDTA by 38% and 34%, respectively.