ABSTRACT
A Gram-stain-negative, facultative aerobic, non-spore-forming, non-motile, non-flagellated, rod-shaped bacterium, designated strain NAU-18T was isolated from an oil-contaminated soil in China. Strain NAU-18T could grow at 10-42 °C (optimum, 30 °C), at pH 5.0-8.0 (optimum, 7.0) and in the presence of 0-2.0% (w/v) NaCl (optimum, 0.5% NaCl in R2A). The predominant fatty acids were C18:1ω7c (71.2%) and Summed feature 2 (5.1%), representing 76.3% of the total fatty acids. The major respiratory quinones were Q9 and Q10. The DNA G + C content of strain NAU-18T was 61.4 mol% based on its draft genome sequence. Genome annotation of strain NAU-18T predicted the presence of 6668 genes, of which 6588 are coding proteins and 80 are RNA genes. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain NAU-18T was a member of the genus Rhizobium and showed 96.93% (with 93.2% coverage) and 96.81% (with 100% coverage) identities with those of Neorhizobium alkalisoli CCBAU 01393T and Rhizobium oryzicola ZYY136T, respectively. In the phylogenetic analysis, strain NAU-18T and R. oryzicola ZYY136T are consistently placed in the same branch. Strain NAU-18T represents a novel species within the genus Rhizobium, for which the name Rhizobium terrae sp. nov. is proposed, with the type strain NAU-18T (=KCTC 62418T = CCTCC AB 2018075T).
Subject(s)
Oil and Gas Fields/microbiology , Rhizobium/classification , Soil Microbiology , Base Composition , China , DNA, Bacterial/genetics , Fatty Acids/chemistry , Genes, Bacterial , Genome, Bacterial/genetics , Hydrogen-Ion Concentration , Nucleic Acid Hybridization , Phylogeny , Quinones/chemistry , RNA, Ribosomal, 16S/genetics , Rhizobium/chemistry , Rhizobium/cytology , Rhizobium/physiology , Sequence Analysis, DNA , Sodium Chloride/metabolism , Species Specificity , TemperatureABSTRACT
A novel Gram-stain-positive, non-motile, rod-shaped bacterial strain designated LIP-1T was isolated from the contaminated soil of a pesticide factory in Xinyi, China, was investigated for its taxonomic allocation by a polyphasic approach. Cell growth occurred at 16-37 °C (optimum, 30 °C), in the presence of 0-2.0 % (w/v) NaCl (optimum, 0 %) and at pH 6.0-9.0 (optimum, pH 7.0). The major fatty acids of strain LIP-1T were anteiso-C15 : 0 (50.8 %), iso-C16 : 0 (17.6 %) and anteiso-C17 : 0 (17.4 %). The cell-wall peptidoglycan type was B2δ with 2,4-diaminobutyric acid as the diagnostic diamino acid. The major polar lipids were diphosphatidylglycerol and two unidentified glycolipids. The major menaquinones were MK-12 and MK-11. The genomic DNA G+C content was approximately 63.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain LIP-1T formed a distinct clade within the radiation of the family Microbacteriaceae and had the highest sequence similarity with Microbacterium ginsengisoli Gsoil 259T (96.01 %) followed by Cryobacterium arcticum SK1T (94.94 %). On the basis of the phylogenetic analyses and distinct phenotypic characteristics, a new genus, namely Huakuichenia gen. nov., is proposed, harbouring the novel species Huakuichenia soli gen. nov., sp. nov. with the type strain LIP-1T (=CCTCC AB 2015422T=KCTC 39698T).
