Chryseobacterium gallinarum sp. nov., isolated from a chicken, and Chryseobacterium contaminans sp. nov., isolated as a contaminant from a rhizosphere sample.

Two yellow-pigmented bacterial strains (100(T) and C26(T)), showing 98.4 % 16S rRNA gene sequence similarity to each other and isolated from a chicken in Germany and as a contaminant from an agar plate of a rhizosphere sample in Alabama, were studied by using a polyphasic taxonomic approach. Cells of both isolates were rod-shaped and stained Gram-negative. A comparison of the 16S rRNA gene sequences of the two organisms with the sequences of the type strains of the most closely related species of the genus Chryseobacterium showed the highest sequence similarities of strains 100(T) and C26(T) to the type strains of Chryseobacterium joostei (respectively 97.5 and 98.2 %), C. viscerum (96.6, 97.8 %), C. gleum (97.1, 97.7 %), C. arthrosphaerae (97.3%, 97.7 %), C. indologenes (97.2, 97.7 %), C. tructae (96.6, 97.6 %), C. jejuense (97.0, 97.6 %) and C. oncorhynchi (96.3, 97.5 %); 16S rRNA gene sequence similarities to members of all other species of the genus Chryseobacterium were below 97.5 %. The fatty acid profiles of both strains consisted of the major fatty acids iso-C15 : 0, summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c), iso-C17 : 1ω9c and iso-C17 : 0 3-OH, but also showed slight differences (absence or presence of C16 : 0 3-OH and iso-C15 : 1 F). DNA-DNA hybridizations between the two strains and between the novel strains and the type strains of C. joostei, C. indologenes, C. jejuense, C. tructae and C. viscerum resulted in relatedness values clearly below 70 %. These DNA-DNA hybridization results and the differentiating biochemical and chemotaxonomic properties showed that both strains 100(T) and C26(T) represent novel species, for which the names Chryseobacterium gallinarum sp. nov. (type strain 100(T) = LMG 27808(T) = CCM 8493(T)) and Chryseobacterium contaminans sp. nov. (type strain C26(T) = LMG 27810(T) = CCM 8492(T)) are proposed.