An exceptionally cold-adapted alpha-amylase from a metagenomic library of a cold and alkaline environment.
Appl Microbiol Biotechnol 2014;
99:717-27. [PMID:
25038927 DOI:
10.1007/s00253-014-5931-0]
[Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 07/01/2014] [Accepted: 07/02/2014] [Indexed: 10/25/2022]
Abstract
A cold-active α-amylase, AmyI3C6, identified by a functional metagenomics approach was expressed in Escherichia coli and purified to homogeneity. Sequence analysis showed that the AmyI3C6 amylase was similar to α-amylases from the class Clostridia and revealed classical characteristics of cold-adapted enzymes, as did comparison of the kinetic parameters K m and k cat to a mesophilic α-amylase. AmyI3C6 was shown to be heat-labile. Temperature optimum was at 10-15 °C, and more than 70 % of the relative activity was retained at 1 °C. The pH optimum of AmyI3C6 was at pH 8-9, and the enzyme displayed activity in two commercial detergents tested, suggesting that the AmyI3C6 α-amylase may be useful as a detergent enzyme in environmentally friendly, low-temperature laundry processes.
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