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Identification and functional characterization of levS, a gene encoding for a levansucrase from Leuconostoc mesenteroides NRRL B-512 F.

Sandra Morales-Arrieta·Maria Elena Rodríguez·Lorenzo Segovia·Agustín López-Munguía·Clarita Olvera-Carranza
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Abstract

A Leuconostoc mesenteroides NRRL B-512 F levansucrase gene, (levS), was isolated, sequenced and cloned in Escherichia coli. The recombinant enzyme was shown to be a fructosyltransferase producing a polymer identified by (13)C-NMR as levan. Based on sequence analysis, we found that this levansucrase is a mosaic protein, bearing structural features of glucosyltransferases in the amino and carboxy terminal regions similarly to inulosucrase from Leuconostoc citreum. The phylogenetic analysis of the C-terminal region domain of levansucrases from L. mesenteroides demonstrates that they group together into a novel putative sub-family of genes and evolved long before all other glucosyltransferases, while their catalytic domain structure is species related.

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Bacterial ProteinsBase SequenceCloning, MolecularEscherichia coliGene ExpressionHexosyltransferasesLeuconostocMolecular Sequence DataPhylogenyProtein Structure, TertiaryRecombinant ProteinsSequence Homology, Amino AcidJournal ArticleResearch Support, Non-U.S. Gov't

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Sandra Morales-Arrieta, Maria Elena Rodríguez, Lorenzo Segovia, Agustín López-Munguía, Clarita Olvera-Carranza. 2006-04-24. Identification and functional characterization of levS, a gene encoding for a levansucrase from Leuconostoc mesenteroides NRRL B-512 F.. https://doi.org/10.1016/j.gene.2006.02.007

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