Two novel actinobacterium strains ZYX-F-536 T and ZYX-F-553 were isolated from marine sediment in Yongxing Island, Hainan Province, China. Based on 16S rRNA gene sequence analysis, the strain ZYX-F-536 T belongs to the genus Micromonospora , with high similarities to strain ZYX-F-553 (99.9%), Micromonospora alfalfae MED01 T (99.0%), Micromonospora auratinigra DSM 44815 T (99.0%), Micromonospora saelicesensis Lupac 09 T ZYX (99.0%), Micromonospora arida LB32 T (99.0%) and Micromonospora foliorum PSH25 T (98.9%). The novel isolate ZYX-F-536 T contained meso -diaminopimelic acid, glycine and d -alanine in the cell wall. The whole-cell sugars were rhamnose, ribose, glucose and xylose. The predominant menaquinones were MK-10(H 4 ) (38.6%), MK-10(H 6 ) (31.2%) and MK-10(H 8 ) (20.1%). The characteristic phospholipids were phosphatidylethanolamine, phosphatidylinositol, diphosphatidylglycerol and two unknown phospholipids. The major fatty acids (>10%) were C 15:0 , C 16:0 , C 17:0 and anteiso-C 17:0 . Genome sequencing showed a DNA G+C content of 71.9 mol%. The low ANI and dDDH values demonstrated that strain ZYX-F-536 T could be readily distinguished from the closely related species. Based on phylogenetic, chemotaxonomic and physiological characteristics, strain ZYX-F-536 T represents a novel species of the genus Micromonospora , for which the name Micromonospora yongxingensis sp. nov. is proposed. The type strain is ZYX-F-536 T (=CCTCC AA 2025094 T =JCM 38260 T ).
Zhu et al. (Wed,) studied this question.