Arch Microbiol 2021 Apr 26;203(3):959-966. Epub 2020 Oct 26.
State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China.
An alkaliphilic actinobacterial strain, designated Hz 6-5, was isolated from saline-alkaline soil from Songnen Plain in north-eastern China. The isolate formed light yellow-colored colonies and its cells were Gram-staining positive, non-motile, and non-spore-forming short rods. The strain was aerobic with optimal growth at 33 °C, pH 9.0, and in the presence of 0.5% (w/v) NaCl or 3% (w/v) KCl. It was catalase-positive and oxidase-negative. The isolate had highest 16S rRNA gene sequence similarities to the type strains of the species Nesternkonia natronophila M8 (98.2%), N. salmonea GY074 (98.1%), and N. sphaerica GY239 (97.4%), and the isolate formed a subclade with the type strains of these species in the neighbor-joining tree based on the 16S rRNA gene sequences. The phylogenetic tree based on the phylogenomic analysis also showed the same results. The DNA‒DNA relatedness (DDH) values of isolate Hz 6-5 with N. natronophila M8, N. halophila DSM 16378, and N. halobia CGMCC 1.2323 were 21.2%, 36.5%, and 32.0%, respectively. The characteristic diamino acid of strain Hz 6-5 was found to be lysine. The respiratory quinones were MK-9, MK-8, MK-7(H), MK-7(H) and MK-7 and the major cellular fatty acids (> 10%) were anteiso-C, anteiso-C and iso-C. The polar lipids detected for strain Hz 6-5 were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol, an unidentified glycolipid, and two unidentified phospholipids. The DNA G + C content of isolate Hz 6-5 was 60.8%. Based on the results of phylogenetic analysis supported by morphological, physiological, chemotaxonomic, and other differentiating phenotypic evidence, strain Hz 6-5 is considered to represent a novel species of the genus Nesterenkonia, for which the name Nesterenkonia haasae sp. nov. is proposed. The type strain is Hz 6-5 (=CPCC 205100=NBRC 113521).