Lactococcus chungangensis sp nov., a lactic acid bacterium isolated from activated sludge foam

The taxonomic position of a Gram-positive coccus, designated strain CAU 28(T), isolated from activated sludge foam was determined by using a polyphasic approach. Based on its cellular morphology and the results of biochemical tests, strain CAU 28(T) was identified tentatively as a member of the genus Lactococcus. Comparative 16S rRNA gene sequence analysis showed that levels of similarity between strain CAU 28 T and the type strains of recognized Lactococcus species ranged from 90.4 to 97.2 %. DNA-DNA hybridization studies showed that strain CAU 28(T) displayed less than 26.1 % relatedness to the type strains of recognized Lactococcus species. The rep-PCR fingerprints revealed that strain CAU 28(T) was well separated from reference Lactococcus species. The combined genotypic and phenotypic data indicate that strain CAU 28(T) represents a novel species of the genus Lactococcus, for which the name Lactococcus chungangensis sp. nov. is proposed. The type strain is CAU 28(T) (=KCTC 13185(T) =CCUG 55099(T)).