Liu Z, Wu G, Wu H. Molecular cloning, and optimized production and characterization of recombinant cyclodextrin glucanotransferase from
Bacillus sp. T1.
3 Biotech 2022;
12:58. [PMID:
35186655 PMCID:
PMC8816995 DOI:
10.1007/s13205-022-03111-8]
[Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 01/08/2022] [Indexed: 11/26/2022] Open
Abstract
Cyclodextrin glucosyltransferase (CGTase) is an enzyme which degrades starch to produce cyclodextrins (CDs). In this study, the β-CGTase producing strain T1 was identified as Bacillus sp. by its morphological characteristics and 16S rDNA sequence analysis. The cgt-T1 gene was cloned and expressed in Escherichia coli. CGTase-T1 was purified by Ni-nitrilotriacetic acid agarose column and the molecular weight was determined as approximately 75 kDa using SDS-PAGE analysis. For the expression of soluble proteins, the optimal induction conditions were 10 h at 25 °C with OD600 at 0.8. The purified CGTase-T1 exhibited maximum activity with an optimal pH and temperature of 6.0 and 65 °C. The enzyme was stable in a pH range of 7.0-10.0, retaining over 85% relative activity for 1 h. CGTase-T1 activity can be significantly enhanced by adding 1 mM Ba2+. Using a soluble starch substrate, the kinetic parameters were revealed with K M and k cat/K M values of 2.75 mg mL-1 and 1253.97 s-1 mL mg-1, respectively. Additionally, the four enzyme activities of CGTase-T1 were determined. The highest conversion rate to CDs (40.9%) was achieved from soluble starch after 8 h of enzyme reaction, where mainly β-CD was produced (79.1% of the total CDs yield), indicating that CGTase-T1 potentially has industrial application prospect.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s13205-022-03111-8.
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