Ralstonia Yabuuchi et al. 1996
General information
Description and emendation
Cells are Gram-negative rod-shaped, motile with single polar or peritrichous flagella or non-motile without flagella. Oxidase activity is vanable by species. Monosaccharides, disaccharides and polyalcohols are oxidized and assimilated as a sole source of carbon and energy, as reported previously. The absence of assimilation of galactose, mannitol, mannose, and sorbitol by the type strain of three Ralstonia species is a differential phenotypic marker to distinguish strains of Ralstonia sp. from those of Burkholderia species Cellular lipids of the, type strains of three Ralstonia species contain phosphatidylethanolamine possessing 2-hydroxy fatty acid at the sn-2 position of the glycerol moiety, similar to those of Burkholderia species. The type strains of three Ralstonia species failed to demonstrate two kinds of ornithine-lipids on two-dimensional thinlayer chromatography and to reveal C19 cyclopropanoic acid in cellular fatty acids The presence of these cellular lipids and fatty acid components were clearly demonstrated in Burkholderia cepacia and the other five Burkholderia species. Flagellar morphology has long been one of the important features for the classification and identification of Gram-negative bacterial strains. However, it is now known that certain species lose their flagella when they become facultatively parasitic. For example, peritrichous Escherichia coli might change to atrichous Shigella species or polar multitrichous Burkholderia pseudomallei to atrichous B. mallei. It is well-known that E. coli is genetically the same species as Shigella sp., as well as B. pseudomallei and B. mallei. Cells of certain species of marine bacteria possess both sheathed polar monotrichous flagella and unsheathed lateral flagella when grown on the surface of semisolid media incubated at around 20°C, while they fail to produce lateral flagella when grown in liquid media at 37°C. Thus, the significance of flagellar morphology in the classification or identification at generic or familiar levels seems to be reduced. Species with different flagellar morphology in one genus, Ralstonia gen. nov. could not be eliminated from the genus. Strains of R. pickettii are isolated from various clinical specimens and hospital environments with doubtful pathogenicity. The heterogeneity of R. solanacearum strains remained to be solved taxonomically. R. solanacearum is known to be pathogenic for Solanum lycopersicum (tomato, potato, tobacco). Also isolated from Casuarina, Strelitzia, ginger, banana, Heloconia, peanut and Pelargonium (M. Gillis, personal communication). The guanine and cytosine content of DNA of the type strains of three species are 64.0, 66.6 and 66.5 mol% (HPLC).
Subdivision(s)
MID | Name | Rank | Taxon ID |
---|---|---|---|
MSG095278 | 'Ralstonia bacterium' | Species | |
M022503010215002 | Ralstonia insidiosa | Species | 190721 |
M022503010215003 | Ralstonia mannitolilytica | Species | 105219 |
M022503010214001 | Ralstonia pickettii | Species | 329 |
M022503010215004 | Ralstonia pseudosolanacearum | Species | 1310165 |
M022503010215005 | Ralstonia solanacearum | Species | 305 |
M022503010215006 | Ralstonia syzygii | Species | 28097 |