Deciphering the Genome of Polyphosphate Accumulating Actinobacterium Microlunatus phosphovorus

• Published in: DNA research Vol. 19; no. 5; pp. 383 - 394
• Main Authors: KAWAKOSH, Akatsuki, NAKAZAWA, Hidekazu, KAMAGATA, Yoichi, NAKAMURA, Kazunori, YAMAZAKI, Shuji, FUJITA, Nobuyuki, FUKADA, Junji, SASAGAWA, Machi, KATANO, Yoko, NAKAMURA, Sanae, HOSOYAMA, Akira, SASAKI, Hiroki, ICHIKAWA, Natsuko, HANADA, Satoshi
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01-10-2012
• Subjects: Acid Anhydride Hydrolases - genetics; Base Sequence; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Genes. Genome; Genetics of eukaryotes. Biological and molecular evolution; Genome, Bacterial - genetics; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Phosphate Transport Proteins - genetics; Phosphotransferases - genetics; Phylogeny; Physical Chromosome Mapping; Polyhydroxyalkanoates - genetics; Polyphosphates - metabolism; Propionibacteriaceae - enzymology; Propionibacteriaceae - genetics; Propionibacteriaceae - metabolism; Sequence Analysis, DNA; polyphosphate; Microlunatus phosphovorus; Nucleotide sequence; polyphosphate accumulating organism; whole genome sequence; Genome; polyhydroxyalkanoate
• ISSN: 1340-2838; 1756-1663
• DOI: 10.1093/dnares/dss020

Polyphosphate accumulating organisms (PAOs) belong mostly to Proteobacteria and Actinobacteria and are quite divergent. Under aerobic conditions, they accumulate intracellular polyphosphate (polyP), while they typically synthesize polyhydroxyalkanoates (PHAs) under anaerobic conditions. Many ecological, physiological, and genomic analyses have been performed with proteobacterial PAOs, but few with actinobacterial PAOs. In this study, the whole genome sequence of an actinobacterial PAO, Microlunatus phosphovorus NM-1(T) (NBRC 101784(T)), was determined. The number of genes for polyP metabolism was greater in M. phosphovorus than in other actinobacteria; it possesses genes for four polyP kinases (ppks), two polyP-dependent glucokinases (ppgks), and three phosphate transporters (pits). In contrast, it harbours only a single ppx gene for exopolyphosphatase, although two copies of ppx are generally present in other actinobacteria. Furthermore, M. phosphovorus lacks the phaABC genes for PHA synthesis and the actP gene encoding an acetate/H(+) symporter, both of which play crucial roles in anaerobic PHA accumulation in proteobacterial PAOs. Thus, while the general features of M. phosphovorus regarding aerobic polyP accumulation are similar to those of proteobacterial PAOs, its anaerobic polyP use and PHA synthesis appear to be different.