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Cloning and characterization of two new thermostable and alkalitolerant α-amylase from the Anoxybacillus species that produce high levels of maltose

Chai, Yen Yen and Raja Abd. Rahman, Raja Noor Zaliha and Md. Illias, Rosli and Goh, Kian Mau (2012) Cloning and characterization of two new thermostable and alkalitolerant α-amylase from the Anoxybacillus species that produce high levels of maltose. Journal of Industrial Microbiology & Biotechnology, 39 . pp. 731-741. ISSN 1367-5435

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Official URL: http://dx.doi.org/10.1007/s10295-011-1074-9

Abstract

Two genes that encode α-amylases from two Anoxybacillus species were cloned and expressed in Escherichia coli. The genes are 1,518 bp long and encode 506 amino acids. Both sequences are 98% similar but are distinct from other well-known α-amylases. Both of the recombinant enzymes, ASKA and ADTA, were purified using an α-CD–Sepharose column. They exhibited an optimum activity at 60°C and pH 8. Both amylases were stable at pH 6–10. At 60°C in the absence of Ca2+, negligible reduction in activity for up to 48 h was observed. The activity half-life at 65°C was 48 and 3 h for ASKA and ADTA, respectively. In the presence of Ca2+ ions, both amylases were highly stable for at least 48 h and had less than a 10% decrease in activity at 70°C. Both enzymes exhibited similar end-product profiles, and the predominant yield was maltose (69%) from starch hydrolysis. To the best of our knowledge, most α-amylases that produce high levels of maltose are active at an acidic to neutral pH. This is the first report of two thermostable, alkalitolerant recombinant α-amylases from Anoxybacillus that produce high levels of maltose and have an atypical protein sequence compared with known α-amylases.

Item Type:Article
Uncontrolled Keywords:Microbiology, biotechnology, Maltose, Thermostable α-amylase, Anoxybacillus, Alkalitolerant
Subjects:Q Science > QR Microbiology
Divisions:Biosciences and Bioengineering (Formerly known)
ID Code:46693
Deposited By: Haliza Zainal
Deposited On:22 Jun 2015 13:56
Last Modified:18 Sep 2017 12:00

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