Williamsia phyllosphaerae sp. nov., isolated from the surface of Trifolium repens leaves.

A Gram-positive-staining, non-endospore-forming actinobacterium, designated C7(T), was isolated from the leaf surface of Trifolium repens. On the basis of 16S rRNA gene sequence analysis, strain C7(T) was shown to belong to the genus Williamsia and was most closely related to Williamsia maris SJS0289/JS1(T) (98.0 % 16S rRNA gene sequence similarity), Williamsia deligens IMMIB RIV-956(T) (96.4 %) and Williamsia serinedens IMMIB SR-4(T) (95.7 %). The quinone system consisted predominantly of the menaquinones MK-9(H(2)), MK-8(H(2)) and MK-7(H(2)). The major components in the polar lipid profile were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol. Mycolic acids were present. These chemotaxonomic traits and the major fatty acids, which were C(16 : 1)ω7c, C(16 : 0), C(18 : 0), C(18 : 1)ω9c and tuberculostearic acid, supported the affiliation of strain C7(T) with the genus Williamsia. Physiological and biochemical analysis revealed clear differences between strain C7(T) and its closest phylogenetic neighbours. Therefore, strain C7(T) represents a novel species, for which the name Williamsia phyllosphaerae sp. nov. is proposed. The type strain is C7(T) ( = CCUG 60465(T) = CCM 7855(T)).