Caenimonas koreensis gen. nov., sp. nov., isolated from activated sludge

A Gram-negative, rod-shaped bacterium, designated strain EMB320^T, was isolated from activated sludge performing enhanced biological phosphorus removal in a sequencing batch reactor. The isolate was strictly aerobic and non-motile. Growth was observed between 10 and 35 °C (optimum 30 °C) and between pH 6.0 and 9.0 (optimum pH 7.0-8.0). The predominant cellular fatty acids of strain EMB320^T were C_16:0, C_18:1ω7c and summed feature 3 (C_16:1ω7c and/or iso-C_15:0 2-OH). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Strain EMB320^T contained ubiquinone-8 (Q-8) as the major respiratory quinone system and 2-hydroxyputrescine and putrescine as the major polyamines, which suggests that it belongs to the Betaproteobacteria. The G + C content of the genomic DNA was 62.7 mol%. Comparative 16S rRNA gene sequence analysis showed that strain EMB320^T formed a phyletic lineage distinct from other genera within the family Comamonadaceae. On the basis of chemotaxonomic data and molecular properties, strain EMB320^T represents a novel genus and species within the family Comamonadaceae, for which the name Caenimonas koreensis sp. nov. is proposed. The type strain of Caenimonas koreensis is EMB320^T (=KCTC 12616^T =DSM 17982^T).