Ferrovibrio soli sp. nov., a novel cellulolytic bacterium isolated from stream bank soil.

Two isolates of bacterial strains A15T and A17 were isolated from stream bank soil in Kyonggi University. Cells were aerobic, Gram-stain-negative, oxidase- and catalase-positive, motile, non-spore-forming, rod-shaped, opaque, and cream coloured. Both strains hydrolysed CM-cellulose. Strains were able to grow at 20-42 °C, pH 5.5-10.0 and at 1.5 % NaCl concentration (w/v). Indole test was positive. Analyses of phylogenetic trees based on its 16S rRNA gene sequences indicated that strain A15T formed a lineage within the family Rhodospirillaceae of the phylum Proteobacteria which was distinct from Ferrovibrio denitrificans S3T (98.4 % sequence similarity) and Ferrovibrio xuzhouensis LM-6T (97.4 %). The sole detected respiratory quinone was Q-10. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and an unidentified aminolipid. The major cellular fatty acids were C19 : 0 cycloω8c, C16 : 0, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C18 : 0cyclo and C12 : 0. The DNA G+C contents of strains A15T and A17 were 63.4 and 62.9 mol%, respectively. DNA-DNA relatedness between strain A15T and other two members of the genus Ferrovibrioranged from 25 to 37 %. The polyphasic characterization revealed strains A15T and A17 represent a novel species in the genus Ferrovibrio, for which the name Ferrovibriosoli sp. nov. is proposed. The type strain is A15T (=KEMB 9005-522T=KACC 19102T=NBRC 112682T).