PARACOCCUS MARCUSII SP. NOV., AN ORANGE GRAM-NEGATIVE COCCUS

Phenotypic, chemotaxonomic and 16S rDNA sequence analysis of an orange Gram-negative coccus that appeared as a contaminant on a nutrient aga r plate delineated a new species of the genus Paracoccus. Phenotypic f eatures of the strain that differ from all or most of the previously d escribed Paracoccus species include its bright orange colour, caused b y the synthesis of large amounts of carotenoids (mainly astaxanthin), and its inability to use nitrate as an electron acceptor in respiratio n. The name Paracoccus marcusii is proposed for this organism. The typ e strain is DSM 11574(T).