The Protein Journal

, Volume 29, Issue 5, pp 355–364

Gene Sequence, Bioinformatics and Enzymatic Characterization of α-Amylase from Saccharomycopsis fibuligera KZ

  • Eva Hostinová
  • Štefan Janeček
  • Juraj Gašperík
Article

DOI: 10.1007/s10930-010-9260-6

Cite this article as:
Hostinová, E., Janeček, Š. & Gašperík, J. Protein J (2010) 29: 355. doi:10.1007/s10930-010-9260-6

Abstract

A fragment coding for a putative extracellular α-amylase, from the genomic library of the yeast Saccharomycopsis fibuligera KZ, has been subcloned into yeast expression vector pVT100L and sequenced. The nucleotide sequence revealed an ORF of 1,485 bp coding for a 494 amino acid residues long protein with 99% identity to the α-amylase Sfamy from S. fibuligera HUT 7212. The S. fibuligera KZ α-amylase (Sfamy KZ) belongs to typical extracellular fungal α-amylases classified in the glycoside hydrolase family 13, subfamily 1, as supported also by clustering observed in the evolutionary tree. Sfamy KZ, in addition to the essential GH13 α-amylase three-domain arrangement (catalytic TIM barrel plus domains B and C), does not contain any distinct starch-binding domain. Sfamy KZ was expressed as a recombinant protein in Saccharomyces cerevisiae and purified to electrophoretic homogeneity. The enzyme had a molecular mass 53 kDa and contained about 2.5% of carbohydrate. The enzyme exhibited pH and temperature optima in the range of 5–6 and 40–50 °C, respectively. Stable adsorption of the enzyme to starch granules was not detected but a low degradation of raw starch in a concentration-dependent manner was observed.

Keywords

Saccharomycopsis fibuligeraYeast α-amylaseProtein bioinformaticsRaw starch digestion

Abbreviations

Sfamy

α-Amylase from Saccharomycopsis fibuligera HUT 7212

Sfamy KZ

α-amylase from S. fibuligera KZ

ALP1

Gene coding for α-amylase from S. fibuligera HUT 7212

LKA1

α-Amylase 1 from Lipomyces kononenkoae

LKA2

α-Amylase 2 from Lipomyces kononenkoae

CBM

Carbohydrate-binding module

SBD

Starch-binding domain

GH

Glycoside hydrolase

AMY1

Barley α-amylase 1 (low pI isozyme)

AMY2

Barley α-amylase 2 (high pI isozyme)

CAZy

Carbohydrate-active enzymes

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Eva Hostinová
    • 1
  • Štefan Janeček
    • 1
  • Juraj Gašperík
    • 1
  1. 1.Institute of Molecular BiologySlovak Academy of SciencesBratislavaSlovakia