Spinactinospora alkalitolerans gen. nov., sp. nov., an actinomycete isolated from marine sediment

Abstract

A novel marine actinomycete, designated CXB654 T, was isolated from marine sediment collected at a depth of 17.5 m near the Yellow Sea Cold Water Mass, China. Optimal growth occurred at 37.0 °C, at pH 7.0-8.0 and in 3-8% (w/v) NaCl. Strain CXB654 T formed branched substrate mycelium without fragmentation. Abundant aerial mycelium differentiated into long or short chains of spores and spores were elliptical and cylindrical with spiny surfaces. Strain CXB654 T contained meso-diaminopimelic acid as the diagnostic diamino acid, and ribose and glucose as the major whole-cell components. Phospholipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol. MK-10(H8), MK-10(H6) and MK-9(H8) were the predominant menaquinones. The major fatty acids were i-C 16:0 (24.46 %), ai-C 17:0 (20.66 %) and C 18:0 (20.14 %). The DNA G+C content was 71.1 mol%. Comparative analysis of 16S rRNA gene sequences showed that the novel strain was most closely related to genera within the family Nocardiopsaceae, but formed a separate lineage. Highest sequence similarities were to Murinocardiopsis flavida DSM 45312 T (96.6 %), Thermobifida halotolerans YIM 90462 T (96.5 %) and Marinactinospora thermotolerans DSM 45154 T (96.1 %). On the basis of phenotypic, chemotaxonomic and phylogenetic distinctiveness, strain CXB654T was considered to represent a novel species in a new genus in the family Nocardiopsaceae, and the name Spinactinospora alkalitolerans gen. nov., sp. nov. is proposed; the type strain is CXB654 T (5DSM 45414T5LMG 25485 T). © 2011 IUMS.