Bacillus barbaricus sp. nov., isolated from an experimental wall painting

In a project concerning bacterial colonization of experimental wall paintings, a large number of isolates have been acquired with high similarities in their whole-cell protein patterns obtained after SDS-PAGE. Of this group, four strains, designated V2-BIII-A2(T), V2-BI-A9, V2-BI-04 and V2-BII-A8, were chosen for further characterization. Banding patterns obtained after ERIC-PCR were barely distinguishable among these four strains, indicating their affiliation within a single species. The isolates also displayed nearly identical biochemical and physiological features. The chemotaxonomic characteristics, including polar lipids, quinone systems, cell-wall diamino acid composition and fatty acid profiles, were in good agreement with those of numerous previously described Bacillus species. 16S rDNA analysis of strain V2-BIII-A2(T) showed that this bacterium belongs to the genus Bacillus, with highest sequence similarities to Bacillus megaterium (94.6%), Bacillus flexus (94.4%) and the alkaliphilic Bacillus cohnii (94.2%). Based on almost identical biochemical, physiological and chemotaxonomic traits, ERIC-PCR-generated genomic fingerprints and comparative 16S rDNA sequence analysis, it is demonstrated that the four isolates represent a novel species of the genus Bacillus, for which the name Bacillus barbaricus sp. nov. is proposed. The type strain is V2-BIII-A2(T) (= CCM 4982(T) = DSM 14730(T)).