Tsukamurella spumae sp. nov., a novel actinomycete associated with foaming in activated sludge plants.

A polyphasic taxonomic study was undertaken to establish the taxonomic position of six representative strains isolated from activated sewage sludge foam. The organisms were found to have chemical and morphological properties consistent with their assignment to the genus Tsukamurella. DNA:DNA relatedness studies showed that five out of the six isolates formed a distinct genomic species, the remaining strain was most closely associated with this taxon. The five isolates had a unique phenotypic profile that served to distinguish them from representatives of the validly described species of Tsukamurella. The combination of the genotypic and phenotypic data indicated that the five strains should be classified as a new species in the genus Tsukamurella. The name proposed for this taxon is Tsukamurella spumae, the type strain is N1171T (= DSM 44.113T = NCIMB 13947T). It was also shown that some of the reference strains were misclassified as Tsukamurella paurometabola.