Comamonas faecalis sp. nov., Isolated from Domestic Pig Feces

A new bacterial strain, designated as FF42^T, was isolated from feces of domestic pigs—collected from Suwon, Korea—and was characterized to determine its taxonomic position. Strain FF42^T was observed to be Gram negative, aerobic, non-spore forming, motile, and rod-shaped cells. Based on the phylogenetic and 16S rRNA sequence analyses, it was revealed that strain FF42^T belonged to the genus Comamonas. The highest degree of sequence similarities was determined to be with Comamonas zonglianii BF-3^T (96.3 %), Comamonas composti CC-YY287^T (96.1 %), and Comamonas nitrativorans 23310^T (95.9 %), while showing less than 95.6 % identity with the remaining Comamonas species. Growth of strain FF42^T occurred between 25 and 40 °C (optimum, 28 °C) and at pH of 5-9 (optimum, pH 6.0). It grew in the presence of 0–3 % (w/v) NaCl while minimally tolerating at 3 % (w/v) NaCl. Biochemical and physiological tests revealed phenotypic differentiation of strain FF42^T to other members of the genus Comamonas. The predominant quinone is ubiquinone (Q-8). The major cellular fatty acids were C_10:0 3OH, C_16:0, summed feature 3 (C_16:1 ω7c/C_16:1 ω6c), and summed feature 8 (C_18:1 ω6c/C_18:1 ω7c), all of which have previously been reported to occur in the species of the genus Comamonas. The G+C molar content for strain FF42^T is 60.2 mol %. Based on phylogenetic and phenotypic analyses, strain FF42^T (=KEMC 1002-058^T=JCM 17561^T) is clearly referred to be a novel species for the genus Comamonas, for which the name Comamonas faecalis sp. nov. is proposed.