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.