title: An exceptionally cold-adapted alpha-amylase from a metagenomic library of a cold and alkaline environment.
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.
authors.affiliation: Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Copenhagen, Denmark.
authors.forename: Jan Kjølhede
authors.initials: JK
authors.lastname: Vester
authors.forename: Mikkel Andreas
authors.initials: MA
authors.lastname: Glaring
authors.forename: Peter
authors.initials: P
authors.lastname: Stougaard
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003080:Cold Temperature; D004777:Environment; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015698:Genomic Library; D006863:Hydrogen-Ion Concentration; D054892:Metagenome; D010802:Phylogeny; D017421:Sequence Analysis; D013379:Substrate Specificity; D000516:alpha-Amylases / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D000516:alpha-Amylases