Phylogenetic and Taxonomic Analyses of Rhodopirellula caenicola Sp. Nov., a New Marine Planctomycetes Species Isolated from Iron Sand

Abstract

A Gram-negative, strictly aerobic, pink-pigmented, non-motile, spherical bacterium designated YM26-125T was isolated from iron sand. Phylogenetic analyses based on the 16S rRNA gene sequence indicated that the new strain was affiliated with the phylum Planctomycetes and shared 96.1% sequence similarity with Rhodopirellula baltica SH 1T. The strain could be also differentiated phenotypically from the Rhodopirellula baltica SH 1T. The major fatty acids of strain YM26-125T were identified as C16:0 and C18:1 ω9c as defined by the MIDI system. Amino acid analysis of cell wall hydrolysates indicated that the novel isolate did not contain diaminopimelic acid in their cell walls. The DNA G+C content was determined to be 57.5 mol%, the major respiratory quinone was identified as menaquinone 6 (MK-6) and a polar lipid profile was present consisting of a phosphatidylglycerol, a diphosphatidylglycerol and three unidentified phospholipids. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel species for which the name Rhodopirellula caenicola sp. nov. is proposed. The type strain of R. caenicola is YM26-125T (=KCTC 32995T=NBRC 110016T).