Actinomadura rudentiformis sp. nov., isolated from soil.

As part of an antibiotic-screening programme, the actinomycete strain HMC1(T) was isolated from soil collected from the banks of the Gamka River in the Swartberg Nature Reserve, Western Cape Province, South Africa. The isolate produced branching vegetative mycelia, which entwined to form rope-like structures. It exhibited antibiosis against Enterococcus faecium VanA (a vancomycin-resistant clinical strain) and Mycobacterium aurum A+. Organic solvent extracts of the culture filtrate and mycelial mass of strain HMC1(T) exhibited moderate antibiosis against Mycobacterium aurum A+, Mycobacterium bovis BCG (Tokyo) and Mycobacterium tuberculosis H37Rv(T). The chemotaxonomic characteristics of strain HMC1(T) corresponded with those of members of the genus Actinomadura. Furthermore, phylogenetic analysis based on the 16S rRNA gene showed that the strain was closely related to members of the genus Actinomadura. Phenotypic and 16S rRNA gene sequence analyses indicated that strain HMC1(T) represents a novel species of the genus Actinomadura, for which the name Actinomadura rudentiformis sp. nov. is proposed. The type strain is HMC1(T) (=DSM 44962(T)=NRRL B-24458(T)).