Segeticoccus rhizosphaerae gen. nov., sp. nov., an actinobacterium isolated from soil of a farming field

A Gram-stain-positive actinobacterial strain, designated YJ01 T , was isolated from a spinach farming field soil at Shinan in Korea. Strain YJ01 T was aerobic, non-motile, non-spore-forming cocci with diameters of 1.5–1.9 µm, and was able to grow at 10–37 °C (optimum, 28–30 °C), at pH 4.5–9.0 (optimum, pH 7.0–8.0) and at salinities of 0–7.5 % (w/v) NaCl (optimum, 1.0 % NaCl). Sequence similarities of the 16S rRNA gene of strain YJ01 T with closely related relatives were in the range 96.2–92.8 %, and the results of phylogenomic analysis indicated that strain YJ01 T was clearly separated from species of genera in the family Intrasporangiaceae showing average nucleotide identity values of 84.2–83.4 %. The predominant isoprenoid quinone was identified as MK-8(H 4 ) and the major fatty acids were iso-C 15 : 0 , iso-C 16:1  h, iso-C 16 : 0 and anteiso-C 17 : 1 ω 9c . The diagnostic diamino acid of the peptidoglycan was ornithine, and the interpeptide bridge was l -Orn–Gly 2 – d -Glu. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylserine, an unidentified phosphatidylglycolipid, two unidentified phosphoaminolipids and an unidentified phosphoglycoaminolipid. The G+C content of the genome was 70.1 mol%. On the basis of phenotypic and chemotaxonomic properties and phylogenetic and phylogenomic analyses using 16S rRNA gene sequences and whole-genome sequences, strain YJ01 T is considered to represent a novel species of a new genus in the family Intrasporangiaceae , for which the name Segeticoccus rhizosphaerae gen. nov. sp. nov. is proposed. The type strain of Segeticoccus rhizosphaerae is YJ01 T (=KACC 19547 T =NBRC 113173 T ).