Streptomyces smaragdinus sp. nov., isolated from the gut of the fungus growing-termite Macrotermes natalensis

The taxonomic position of a novel aerobic, Gram-positive actinobacteria, designated strain RB5(T), was determined using a polyphasic approach. The strain, isolated from the gut of the fungus-farming termite Macrotermes natalensis, showed morphological, physiological and chemotaxonomic properties typical of the genus Streptomyces . Based on 16S rRNA gene sequence analysis, the closest phylogenetic neighbour of RB5(T) was Streptomyces polyrhachis DSM 42102(T) (98.87 %). DNA–DNA hybridization experiments between strain RB5(T) and S. polyrhachis DSM 42102(T) resulted in a value of 27.4 % (26.8 %). The cell wall of strain RB5(T) contained ll-diaminopimelic acid as the diagnostic amino acid. Mycolic acids and diagnostic sugars in whole-cell hydrolysates were not detected. The strain produced the following major phospholipids: diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol-mannoside and phosphatidylserine. The menaquinone profile showed hexa- and octahydrogenated menaquinones containing nine isoprene units [MK-9(H(6)) and MK-9(H(8))]. The strain exhibited a fatty acid profile containing the following major fatty acids: 12-methyltridecanoic acid (iso-C(14 : 0)) 12-methyltetradecanoic acid (anteiso-C(15 : 0)), 13-methyltetradecanoic acid (iso-C(15 : 0)) and 14-methylpentadecanoic acid (iso-C(16 : 0)). Here, we propose a novel species of the genus Streptomyces – Streptomyces smaragdinus with the type strain RB5(T) (=VKM Ac-2839(T)=NRRL B65539(T)).