Molecular cloning of levan fructotransferase gene from Arthrobacter ureafaciens K2032 and its expression in Escherichia coli for the production of difructose dianhydride IV.

Laboratory of Metabolic Engineering, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Korea.
Letters in Applied Microbiology (Impact Factor: 1.75). 02/2005; 40(3):228-34. DOI: 10.1111/j.1472-765X.2005.01658.x
Source: PubMed

ABSTRACT To clone and overexpress a novel levan fructotransferase gene lftA from Arthrobacter ureafaciens K2032.
The lftA gene, encoding a levan fructotransferase (LFTase) of 521 amino acids (aa) residues, was cloned from the genomic DNA of A. ureafaciens K2032, and overexpressed in Escherichia coli. The recombinant LFTase overexpressed in E. coli was then used to produce a difructose dianhydride (DFA IV) from levan. DFA IV crystals with 97% purity could be obtained from the reaction mixture in 83.7% yield by using a natural crystallization method.
The lftA gene cloned from A. ureafaciens K2032 encode a novel levan fructotransferase which produces difructose dianhydride (DFA IV) from levan.
Levan fructotransferase is a useful enzyme with great promise in the production of DFA IV and various fructosides.

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