Georgenia muralis gen. nov., sp. nov., a novel actinobacterium isolated from a medieval wall painting.

Two bacterial strains, designated 1A-C(T) and 3A-1, were studied and, using these results and previously published data, taxonomically classified. Cells of the strains exhibited a rod-coccus cycle. The peptidoglycan determined for 1A-C(T) was of type A4alpha with lysine as the diagnostic cell-wall diamino acid and an interpeptide bridge of L-Lys <-- L-Glu. The menaquinone systems of the two strains contained MK-8(H4) (82-94%) and MK-7(H4) (3-11%). The polar lipid profiles consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol mannoside, two unidentified phospholipids and an unidentified glycolipid. The fatty acid profiles contained predominantly ai-C15:0 and significant amounts of i-C14:0 and i-C15:1 fatty acids. Genomic fingerprints clearly distinguished strains 1A-C(T) and 3A-1 from each other. DNA-DNA relatedness between the two strains (92%) demonstrated that they are members of a single species. Analyses of the 16S rDNA sequences of strains IA-C(T) and 3A-1, which were almost identical (99.6% sequence similarity), and comparison with corresponding sequences demonstrated that they represent a novel lineage within the suborder Micrococcineae, most closely related to species of the genera Beutenbergia, Bogoriella and Cellulomonas (94.7-95.7% sequence similarity). The results demonstrate that the two strains are members of a single new genus and a single novel species. Thus, the name Georgenia muralis gen. nov., sp. nov. is proposed. The type strain is strain 1A-C(T) (= DSM 14418T = CCM 4963T). Another strain of the species is strain 3A-1 (= DSM 14419 = CCM 4964).