Chryseobacterium sediminis sp. nov., isolated from a river sediment.

Abstract

A slightly yellow-pigmented strain (IMT-174T) isolated from a river sediment in Guyana was studied in detail for its taxonomic position. Cells of the isolate appeared rod-shaped and stained Gram-negative. Comparative 16S rRNA gene sequence analysis showed that the isolate had the highest sequence similarities to type strains of Chryseobacterium rhizoplanae (99.0 %), Chryseobacterium viscerum (98.9 %), Chryseobacterium lactis (98.8 %) and Chryseobacterium indologenes (98.6 %). The 16S rRNA gene sequence similarities to all other species of the genus Chryseobacterium were below 98.5 %. Fatty acid analysis of whole-cell hydrolysates of the strain resulted in a pattern typical of members of the genus Chryseobacterium, with fatty acids iso-C15 : 0, iso-C15 : 0 2-OH, iso-C17 : 1ω9c and iso-C17 : 0 3-OH as major compounds. The polyamine pattern contained predominantly sym-homospermidine. The major quinone was menaquinone MK-6 and the only lipid identified in the polar lipid profile was phosphatidylethanolamine. In addition, 13 unidentified lipids were detected in moderate to major amounts. DNA-DNA hybridizations with type strains of C. rhizoplanae, C. viscerum, C. lactis and C. indologenes resulted in values below 70 %. In addition to the genotypic differences, differentiating biochemical and chemotaxonomic properties confirmed that isolate IMT-174T represents a novel species, for which the name Chryseobacterium sediminis sp. nov. (type strain IMT-174T = LMG 28695T = CIP 110895T) is proposed.