Abstract

A thermostable cyclodextrin glucanotransferase (CGTase) was isolated from a Bacillus stearothermophilus strain, ET1, which was screened from Korean soil. The corresponding CGTase gene cloned in Escherichia coli shared 84% and 88% identity with CGTase genes from other B. stearothermophilus strains at the nucleotide and amino acid sequence level, respectively. The enzyme was purified to apparent homogeneity by β-cyclodextrin (CD) affinity chromatography and high-performance liquid chromatography. The enzyme had an apparent molecular mass of 66,800 Da and a pI of 5.0. The optimum pH for the enzyme-catalyzed reaction was pH 6.0, and the optimum temperature was observed at 80 °C. Thermostability of the enzyme was enhanced by Ca2+. A 13% (w/v) cornstarch solution was liquefied and converted to CDs solely using this enzyme. The cornstarch conversion rate was 44% and α-, β-, and γ-CDs were produced in the ratio of 4.2:5.9:1. Keywords: Cyclodextrin glucanotransferase; thermostability; cyclodextrin; Bacillus stearothermophilus

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.