Production of long-chain levan by a sacC insertional mutant from Bacillus subtilis 327UH

A hyper extracellular protein producer, Bacillus subtilis 327UH, produced large amounts of levan in a medium containing 20% sucrose, and the yield of levan after 10 hours was more than 60%, when based on the fructose amount of sucrose. After transformation of 327UH with a levanase-deficient 168SC (sacC::Cm-r) chromosomal DNA, a Cm-r transformant 327UHSC (sacC::Cm-r degSU(Hy)) produced 3 times longer levan than that of the wild type.