Janibacter limosus gen. nov., sp. nov., a new actinomycete with meso-diaminopimelic acid in the cell wall.

New gram-positive bacteria were isolated from 1-year-old sludge from a wastewater treatment plant. The isolates are coccoid to rod-shaped, nonmotile aerobes that form neither spores nor mycelia. They are characterized by a peptidoglycan with directly cross-linked meso-diaminopimelic acid (type A1 gamma), by the presence of menaquinone MK-8(H4), and by the lack of mycolic acids. The strains have complex fatty acid patterns with i-C16:0 and straight-chain saturated and unsaturated fatty acids as major components. The G + C content of the DNA is 70 mol%. The results of chemotaxonomic studies and a 16S ribosomal DNA sequence comparison support our proposal to assign these bacteria to a new genus, the genus Janibacter gen. nov.; the type species is Janibacter limosus sp. nov., and the type strain of J. limosus is strain HKI 83 (= DSM 11140).