Fodinicola feengrottensis gen. nov., sp. nov., an actinomycete isolated from a medieval mine.

A filamentous, Gram-positive actinobacterium was isolated from acidic rocks in a medieval alum slate mine and was investigated by means of a polyphasic taxonomic approach. A 16S rRNA gene sequence similarity study indicated that strain HKI 0501(T) forms an individual line of descent and is related to certain members of the suborder Frankineae, order Actinomycetales (<95 % sequence similarity). Distance-matrix and neighbour-joining analyses set the branching point of the novel isolate between two clades, one being represented by members of the genus Cryptosporangium (family 'Kineosporiaceae') and the other by members of the genera Frankia and Acidothermus (family Frankiaceae and family Acidothermaceae, respectively). The organism had meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan and xylose as the characteristic cell-wall sugar. The muramic acid in the peptidoglycan was found to be N-acetylated. The major menaquinones were MK-9(H(4)), MK-9(H(6)) and MK-9(H(8)) and the fatty acid profile was characterized by the predominance of iso-C(16 : 0), 10-methyl C(17 : 0), C(17 : 1) cis9 and 10-methyl iso-C(18 : 0). The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol and several unknown phospholipids and glycolipids. Mycolic acids were absent. The DNA G+C content was 65 mol%. The distinct phylogenetic position and the phenotypic markers that clearly separate the novel organism from all other members of the suborder Frankineae indicate that strain HKI 0501(T) represents a novel genus and species, for which the name Fodinicola feengrottensis gen. nov., sp. nov. is proposed. The type strain of Fodinicola feengrottensis is HKI 0501(T) (=DSM 19247(T) =JCM 14718(T)).