Chryseobacterium zeae sp. nov., Chryseobacterium arachidis sp. nov., and Chryseobacterium geocarposphaerae sp. nov. isolated from the rhizosphere environment.

Four yellow pigmented strains (91A-561(T), 91A-576, 91A-593(T), and JM-1085(T)) isolated from plant materials, showed 97.2-98.7 % 16S rRNA gene sequence similarities among each other and were studied in a polyphasic approach for their taxonomic allocation. Cells of all four isolates were rod-shaped and stained Gram-negative. Comparative 16S rRNA gene sequence analysis showed that the four bacteria had highest sequence similarities to Chryseobacterium formosense (97.2-98.7 %), Chryseobacterium gwangjuense (97.1-97.8 %), and Chryseobacterium defluvii (94.6-98.0 %). Sequence similarities to all other Chryseobacterium species were below 97.5 %. Fatty acid analysis of the four strains showed Chryseobacterium typical profiles consisting of major fatty acids C15:0 iso, C15:0 iso 2-OH/C16:1 ω7c, C17:1 iso ω9c, and C17:0 iso 3-OH, but showed also slight differences. DNA-DNA hybridizations with type strains of C. gwangjuense, C. formosense, and C. defluvii resulted in values below 70 %. Isolates 91A-561(T) and 91A-576 showed DNA-DNA hybridization values >80 % indicating that they belonged to the same species; but nucleic acid fingerprinting showed that the two isolates represent two different strains. DNA-DNA hybridization results and the differentiating biochemical and chemotaxonomic properties showed, that both strains 91A-561(T) and 91A-576 represent a novel species, for which the name Chryseobacterium geocarposphaerae sp. nov. (type strain 91A-561(T)=LMG 27811(T)=CCM 8488(T)) is proposed. Strains 91A-593(T) and JM-1085(T) represent two additional new species for which we propose the names Chyrseobacterium zeae sp. nov. (type strain JM-1085(T)=LMG 27809(T), =CCM 8491(T)) and Chryseobacterium arachidis sp. nov. (type strain 91A-593(T)=LMG 27813(T), =CCM 8489(T)), respectively.