Chromobacterium piscinae sp. nov. and Chromobacterium pseudoviolaceum sp. nov., from environmental samples

Abstract

Two strains (LMG 3947 and LMG 3953) of motile, Gram-negative, violet-pigmented bacteria, respectively isolated in 1972 and before 1953 from environmental samples and previously assigned to Chromobacterium violaceum, were studied again in detail for their taxonomic position. 16S rRNA gene sequence analysis showed that both strains clustered together with the type strain of Chromobacterium violaceum (99.8 % sequence similarity for strain LMG 3953(T) and 98.9 % sequence similarity for LMG 3947(T)). recA sequence similarities were significantly lower (95-96 %), and fatty acid profiles were also different from those reported for C. violaceum and other Chromobacterium species. Both strains exhibit polar-lipid profiles consisting of the major compound phosphatidylethanolamine and moderate amounts of phosphatidylglycerol in addition to some minor lipids. The quinone systems consist of the major compound ubiquinone Q-8 and moderate amounts of Q-7. Polyamine patterns are composed of the major compounds putrescine and 2-hydroxyputrescine, moderate amounts of 1,3-diaminopropane and variable amounts of cadaverine and spermidine. The results of DNA-DNA hybridizations and physiological as well as biochemical tests allowed both genotypic and phenotypic differentiation of the two strains from described Chromobacterium species. It is evident from the genotypic and phenotypic data that both strains represent novel species in the genus Chromobacterium, for which we propose the names Chromobacterium piscinae sp. nov. (type strain LMG 3947(T) =CCM 3329(T)) and Chromobacterium pseudoviolaceum sp. nov. (type strain LMG 3953(T) =CCM 2076(T) =NCIMB [corrected] 8182(T)).