Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8328180 | International Journal of Biological Macromolecules | 2018 | 7 Pages |
Abstract
Amylosucrase (ASase) is a glucosyltransferase, which catalyzes the de novo synthesis of amylose-like polymers from sucrose. In the present study, ASase from Neisseria subflava (NsAS) was cloned, sequenced, and expressed in Escherichia coli. The production of NsAS was achieved by inducting gene expression with 0.2â¯mM isopropyl-β-d-thiogalactopyranoside. The molecular mass of the Ni-NTA column purified NsAS analyzed by SDS-PAGE was determined to be 72â¯kDa. NsAS exhibited maximal activity at 45â¯Â°C and pH 8.0, and showed strong thermal stability at 40â¯Â°C with a half-life of 385â¯h. The reaction pattern of NsAS at [sucrose] range of 0.1-1.0â¯M showed that at 0.7â¯M of [sucrose], the production yield of insoluble linear α-(1,4)-glucans reached 24% maximum, and any further increase in [sucrose] resulted in a slight decrease in yield. Meanwhile, the production yield of turanose significantly increased from 16 to 29% by increasing [sucrose] from 0.1 to 1.0â¯M. The synthesized glucan had degrees of polymerization (DP); for 0.1, 0.4, 0.7, and 1.0â¯M sucrose, the DP values were 77, 49, 39, and 31 respectively. These results suggested that NsAS would be a promising candidate for food industrial production of linear α-(1,4)-glucans and turanose as a next generation sweetener.
Keywords
Related Topics
Life Sciences
Biochemistry, Genetics and Molecular Biology
Biochemistry
Authors
Min-Oh Park, Murugesan Chandrasekaran, Sang-Ho Yoo,