Gemmatimonas aurantiaca T-27 (= NBRC 100505) was isolated as a slow growing bacterium from an anaerobic-aerobic sequential batch reactor operated
under enhanced biological phosphorous removal (EBPR) conditions for wastewater treatment.
The 16S rRNA sequence analysis indicated that the isolate was phylogenetically distant from any known bacterial species.
This led to the proposal, for the first time in Japan, of a new valid phylum, Gemmatimonadetes. Members of the phylum Gemmatimonadetes
are frequently found by culture-independent surveys in various environments, such as soils and sponges, but only a few isolates were reported to date.
Physiological and metabolic features of microbes belonging to this phylum were therefore hardly characterized.
Genome analysis of G. aurantiaca
T-27 revealed a circular chromosome consisting of 4,636,964 bp with 64.28% G+C content.
3,935 open reading frames, 48 tRNA genes and single rRNA operon were predicted. Many of the essential genes identified in model organisms
such as Escherichia coli
and Bacillus subtilis
were also found in G. aurantiaca
suggesting that basic cellular systems were not much different from other microbes. Pathway reconstruction suggested that
T-27 could grow both under aerobic and anaerobic conditions, being consistent with the operating conditions of
the anaerobic-aerobic sequential batch reacter which this bacterium was isolated from. Furthermore, G. auratiaca
T-27 genome encoded significantly large numbers of signal transduction components, sigma factors and transporters.
These genomic features would provide an insight into the life style of G. aurantiaca
, and facilitate isolation of not-yet-cultivated Gemmatimonadetes