Two novel Gram-stain negative, motile, non-spore forming, facultative aerobic and short rod shaped bacterial strains, designated U15(T) and U32, were isolated from soil obtained from Ukraine. The sequence similarity of the 16S rRNA gene between strains U15(T) and U32 was found to be 99.5 %. Phylogenetic analysis based on 16S rRNA gene sequences confirmed that new bacteria belong to the genus Noviherbaspirillum. The closest member of the genus was found to be Noviherbaspirillum malthae (97.0 %) followed by Noviherbaspirillum suwonensis (96.3 %). The novel isolates was observed to grow optimally at 30 °C and pH 7.0. The major fatty acids present in the two strains were identified as summed feature 3 (C16:1 ω7c/C16:1 ω6c), C16:0, and summed feature 8 (C18:1 ω7c/C18:1 ω6c). Ubiquinone 8 was identified as the respiratory quinone component for both the strains. The polar lipid (L) profile contained phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, aminophospholipid, unidentified aminolipid and unidentified Ls, and putrescine and 2-hydroxyputrescine as major polyamines. The G+C content of the DNA for the strain U15(T) was found to be 61.2 mol%. The DNA-DNA relatedness between U15(T) and U32 and closely related species was less than 40 %. Based on the polyphasic taxonomic analysis, a new species, Noviherbaspirillum humi sp. nov., is proposed. The type strain is strain U15(T) = JCM 19873(T) = KEMB 7305-102(T).
Keywords: 16S rRNA; Bacteria; Noviherbaspirillum; Polyphasic; Taxonomy.