The genus Kitasatospora was proposed in 1982. Although Kitasatospora strains resemble Streptomyces strains in morphology, they are clearly different in cell-wall composition, as they contain both LL- and meso-diaminopimelic acid. Aerial and submerged spores contain LL-, while vegetative and submerged mycelia contain mainly meso- in their cell walls. Currently, 23 species have been validly proposed. Members of the genus Kitasatospora form a tight cluster and represent a legitimate genus distinct from Streptomyces on the basis of phylogenetic analysis of 16S rRNA gene sequences. A variety of biologically active compounds have been found from Kitasatospora strains and structures of these compounds are extremely diverse. Genome sequences of 15 strains published so far are about 7-9 Mb in size and contain many genes governing secondary metabolites.