I soptericola croceus sp. nov., a novel actinobacterium isolated from saline–alkali soil

A novel actinomycete, designated strain q2 T , was isolated from the saline–alkaline soil, collected from Daqing, Heilongjiang province, China. The results of phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain q2 T belongs to the genus Isoptericola , and showed the highest sequence similarity to Isoptericola halotolerans KCTC 19046 T (98.48%) and Isoptericola chiayiensis KCTC 19740 T (98.13%), respectively. The average nucleotide identity values between strain q2 T and other members of the genus Isoptericola were lower than 95% recommended for distinguishing novel prokaryotic species. Cells of strain q2 T were Gram-staining-positive, aerobic, non-motile, rod-shaped and non-spore-forming. Colonies of strain q2 T were golden-yellow pigmented, tidy edged and smooth surfaced. Growth occurred at 15–37 °C (optimum, 29 °C), pH 7.0–10.0 (optimum, pH 8.0). The predominant respiratory quinones were MK-9(H 4 ) and MK-9(H 2 ). The main detected polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, and phosphatidylinositol mannoside. The peptidoglycan compositions were l -alanine, d -aspartic, l -glutamic acid and l -lysine (type A4α). The major cellular fatty acids (> 10%) were anteiso-C 15:0 , iso-C 15:0 , and anteiso-C 17:0 . The G+C content of the genomic DNA was determined to be 69.7%. Based on the phenotypic, physiological, genotypic, and phylogenetic data, strain q2 T represents a novel species of the genus Isoptericola , for which the name Isoptericola croceus sp. nov. is proposed. The type strain is q2 T (= GDMCC 1.2923 T = KCTC 49759 T ).