title: Deciphering the genome of polyphosphate accumulating actinobacterium Microlunatus phosphovorus.
abstract: 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.
authors.affiliation: Biological Resource Center, National Institute of Technology and Evaluation, 2-10-49 Nishihara, Tokyo 151-0066, Japan.
authors.forename: Akatsuki
authors.initials: A
authors.lastname: Kawakoshi
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Nakazawa
authors.forename: Junji
authors.initials: J
authors.lastname: Fukada
authors.forename: Machi
authors.initials: M
authors.lastname: Sasagawa
authors.forename: Yoko
authors.initials: Y
authors.lastname: Katano
authors.forename: Sanae
authors.initials: S
authors.lastname: Nakamura
authors.forename: Akira
authors.initials: A
authors.lastname: Hosoyama
authors.forename: Hiroki
authors.initials: H
authors.lastname: Sasaki
authors.forename: Natsuko
authors.initials: N
authors.lastname: Ichikawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hanada
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Kamagata
authors.forename: Kazunori
authors.initials: K
authors.lastname: Nakamura
authors.forename: Shuji
authors.initials: S
authors.lastname: Yamazaki
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Fujita
mesh_terms: D017766:Acid Anhydride Hydrolases / Q000235:genetics; D001483:Base Sequence; D016680:Genome, Bacterial / Q000235:genetics*; D008969:Molecular Sequence Data; D028061:Phosphate Transport Proteins / Q000235:genetics; D010770:Phosphotransferases / Q000235:genetics; D010802:Phylogeny; D020161:Physical Chromosome Mapping; D054813:Polyhydroxyalkanoates / Q000235:genetics; D011122:Polyphosphates / Q000378:metabolism*; D011423:Propionibacteriaceae / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D017422:Sequence Analysis, DNA
chemical_list: D028061:Phosphate Transport Proteins; D054813:Polyhydroxyalkanoates; D011122:Polyphosphates; D010770:Phosphotransferases; D017766:Acid Anhydride Hydrolases; C020137:exopolyphosphatase