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Alkaline active maltohexaose-forming α-amylase from Bacillus halodurans LBK 34

Hashim, Suhaila LU ; Delgado, Osvaldo LU ; Martinez, Alejandra LU ; Hatti-Kaul, Rajni LU ; Mulaa, Francis J and Mattiasson, Bo LU (2005) In Enzyme and Microbial Technology 36(1). p.139-146
Abstract
The gene encoding Amy 34, a maltohexaose-forming α-amylase from Bacillus halodurans LBK 34 isolated from Lake Bogoria, Kenya, was cloned and sequenced. The mature peptide consists of 958 amino acids with a theoretical molecular weight of 107.2 kDa and pI 4.41, respectively. The gene was expressed in Escherichia coli and the recombinant enzyme purified to homogeneity by a combination of metal chelate affinity and size exclusion chromatography. The pure enzyme exhibited optimum activity at 60 °C and pH 10.5–11.5. The enzyme retained over 60% activity after incubation at 55 °C for 4 h and was most stable at pH 9.0. Complete inhibition of enzyme activity was observed in presence of 5 mM Cu2+, Fe2+, Fe3+, Mn2+ and 5 mM EDTA. The enzyme... (More)
The gene encoding Amy 34, a maltohexaose-forming α-amylase from Bacillus halodurans LBK 34 isolated from Lake Bogoria, Kenya, was cloned and sequenced. The mature peptide consists of 958 amino acids with a theoretical molecular weight of 107.2 kDa and pI 4.41, respectively. The gene was expressed in Escherichia coli and the recombinant enzyme purified to homogeneity by a combination of metal chelate affinity and size exclusion chromatography. The pure enzyme exhibited optimum activity at 60 °C and pH 10.5–11.5. The enzyme retained over 60% activity after incubation at 55 °C for 4 h and was most stable at pH 9.0. Complete inhibition of enzyme activity was observed in presence of 5 mM Cu2+, Fe2+, Fe3+, Mn2+ and 5 mM EDTA. The enzyme displayed 80% of its original activity in presence of 1% (w/v) SDS and was stable in presence of up to 5 mM DTT. Maltohexaose (G6) was the main initial product of starch hydrolysis while other products formed were G4 > G2 > G5 > G3 and G1. The main end product of the enzyme's action on amylose, amylopectin and maltodextrin is maltotetraose. Amy 34 could not hydrolyse pullulan, α and β-cyclodextrin but could hydrolyse γ-cyclodextrin to produce glucose, maltose and maltotetraose. Maltotetraose was the smallest α-(1–4) linked maltooligosaccharide that could be hydrolysed by the enzyme. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
B. halodurans, alkaliphile, maltohexaose, amylase
in
Enzyme and Microbial Technology
volume
36
issue
1
pages
139 - 146
publisher
Elsevier
external identifiers
  • wos:000226195800018
  • scopus:9944259026
ISSN
0141-0229
DOI
10.1016/j.enzmictec.2004.07.017
language
English
LU publication?
yes
id
9c657bb0-0bda-4bbd-8f6a-bd98e9b5f3b7 (old id 141629)
date added to LUP
2007-07-02 11:28:41
date last changed
2017-11-19 03:25:38
@article{9c657bb0-0bda-4bbd-8f6a-bd98e9b5f3b7,
  abstract     = {The gene encoding Amy 34, a maltohexaose-forming α-amylase from Bacillus halodurans LBK 34 isolated from Lake Bogoria, Kenya, was cloned and sequenced. The mature peptide consists of 958 amino acids with a theoretical molecular weight of 107.2 kDa and pI 4.41, respectively. The gene was expressed in Escherichia coli and the recombinant enzyme purified to homogeneity by a combination of metal chelate affinity and size exclusion chromatography. The pure enzyme exhibited optimum activity at 60 °C and pH 10.5–11.5. The enzyme retained over 60% activity after incubation at 55 °C for 4 h and was most stable at pH 9.0. Complete inhibition of enzyme activity was observed in presence of 5 mM Cu2+, Fe2+, Fe3+, Mn2+ and 5 mM EDTA. The enzyme displayed 80% of its original activity in presence of 1% (w/v) SDS and was stable in presence of up to 5 mM DTT. Maltohexaose (G6) was the main initial product of starch hydrolysis while other products formed were G4 > G2 > G5 > G3 and G1. The main end product of the enzyme's action on amylose, amylopectin and maltodextrin is maltotetraose. Amy 34 could not hydrolyse pullulan, α and β-cyclodextrin but could hydrolyse γ-cyclodextrin to produce glucose, maltose and maltotetraose. Maltotetraose was the smallest α-(1–4) linked maltooligosaccharide that could be hydrolysed by the enzyme.},
  author       = {Hashim, Suhaila and Delgado, Osvaldo and Martinez, Alejandra and Hatti-Kaul, Rajni and Mulaa, Francis J and Mattiasson, Bo},
  issn         = {0141-0229},
  keyword      = {B. halodurans,alkaliphile,maltohexaose,amylase},
  language     = {eng},
  number       = {1},
  pages        = {139--146},
  publisher    = {Elsevier},
  series       = {Enzyme and Microbial Technology},
  title        = {Alkaline active maltohexaose-forming α-amylase from Bacillus halodurans LBK 34},
  url          = {http://dx.doi.org/10.1016/j.enzmictec.2004.07.017},
  volume       = {36},
  year         = {2005},
}