Hymenobacter negativus sp. nov., bacteria isolated from mountain soil collected in South Korea.

Two novel Gram-negative bacterial strains BT442T and BT584 were isolated from dry soil collected in mountains Busan and Guri, Korea during wintertime. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains BT442T and BT584 both belong to a distinct lineage within the genus Hymenobacter (family Hymenobacteraceae, order Cytophagales, class Cytophagia). Strain BT442T was closely related to Hymenobacter soli PB17T (98.0% 16S rRNA gene similarity) and Hymenobacter terrae POA9T (97.6%). No other recognized bacterial species showed more than 97% 16S rRNA gene sequence similarity to strains BT442T. The genome size of strain BT442T was 5,143,362 bp. Bacterial growth was observed at 10-30 °C (optimum 25 °C), pH 6.0-8.0 (optimum pH 6.0) in R2A agar and in the presence up to 1% NaCl. The major cellular fatty acids of strains BT442T and BT584 were iso-C15:0, anteiso-C15:0 and summed feature 3 (C16:1 ω6c / C16:1 ω7c). In addition, their predominant respiratory quinone was MK-7. The major polar lipids of strains BT442T and BT584 were identified to be phosphatidylethanolamine, aminophospholipid, and aminolipid. Based on the biochemical, chemotaxonomic, and phylogenetic analyses, strains BT442T and BT584 are novel bacterial species within the genus Hymenobacter, and the proposed name is Hymenobacter negativus. The strain type of Hymenobacter negativus is BT442T (= KCTC 72902T = NBRC XXXXT).