Microbacterium kitamiense sp. nov., a new polysaccharide-producing bacterium isolated from the wastewater of a sugar-beet factory.

Two strictly aerobic, heterotrophic and mesophilic new organisms, strains Kitami A1 and Kitami C2T, were isolated from the wastewater of a sugar-beet factory in Kitami City, Hokkaido, Japan. In batch cultures, these organisms produced both insoluble and soluble exopolysaccharides (EPSs) utilizing sucrose as the sole carbon source. The G + C contents of the strains Kitami C2T and Kitami A1 were 69.2 mol%. Both strains had anteiso-C15:0 acid, anteiso-C17:0 acid and iso-C16:0 as major components. The major isoprenoid quinones from these strains included menaquinone-11 and menaquinone-12. Physiological and biochemical characterization, phylogenetic analysis and DNA-DNA relatedness indicated that these two organisms are new species of the genus Microbacterium, for which the name Microbacterium kitamiense is proposed. The type strain of M. kitamiense is strain Kitami C2T (= JCM 10270T).