Cloning of a dextransucrase gene (fmcmds) from a constitutive dextransucrase hyper-producing Leuconostoc mesenteroides B-512FMCM developed using VUV

Dextransucrase (FMCMDS) from Leuconostoc mesenteroides B-512FMCM, a dextran sucrase constitutive and hyper-producing strain, catalyzes the synthesis of dextran from sucrose. The coding region for fmcmds was isolated and sequen ced. It consisted of an open reading frame (ORF) of 4699 bp, coding for a 1 527 amino acid protein with a molecular mass of 170 kDa. However, it showed a dextransucrase activity band at 180 kDa in SDS-PAGE. Only one nucleotide changed in the promoter site and two amino acid residues were changed in t he structural gene from that of the parent L. mesenteroides NRRL B-512F dsr S; an inducible dextransucrase gene of low productivity.