Comamonas squillarum sp. nov., Isolated from Intestine of Red Swamp Crayfish (Procambarus clarkii)

A novel bacterium, designated as strain PR12^T, was isolated from intestine of red swamp crayfish (Procambarus clarkii), which appeared as creamy white colonies on TSA plates. Growth occurred at temperatures of 4-37 °C (28-30 °C optimal), pH of 6.0-9.0 (7.0-8.5 optimal), and with 0-4.0% (w/v) NaCl (0-1.5% optimal). The cells were Gram-stain-negative, rod-shaped, non-motile, aerobic, oxidase- and catalase-positive, and chemoorganotrophic. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain PR12^T was related to members of the genus Comamonas and shared the highest sequence similarities with Comamonas koreensis KCTC 12005^T (99.0%), Comamonas sediminis S3^T (98.8%), and Comamonas piscis CN1^T (98.0%). Whole genome size of PR12^T was 5,111,300 bp and DNA G + C content was 63.5%. The major cellular fatty acids (> 10%) were C_16:0, C_17:0 cyclo, summed features 3 (C_16:1ω6c and/or C_16:1ω7c) and summed features 8 (C_18:1ω6c and/or C_18:1ω7c). The major respiratory quinone was Q-8 and the major polar lipids contained diphosphatidylglycerol (DPG), phosphatidylglycerol (PG) and phosphatidylethanolamine (PE). Based on the digital DNA-DNA hybridization, phylogenetic analysis, average nucleotide identity, average aminoacid identity as well as biochemical characteristics, strain PR12^T was clearly distinguishable from all recognized type strains of the genus Comamonas and represents a novel species, for which the name Comamonas squillarum sp. nov. is proposed. The type strain is PR12^T (= MCCC 1K08379^T = JCM 35896^T).