In taxonomy, Ruegeria is a genus of the Rhodobacteraceae. This genus was formerly known as the marine Agrobacterium before they were reclassified in 1998. It bears in fact the name of Hans-Jürgen Rüger, a German microbiologist, for his contribution to the taxonomy of marine species of Agrobacterium. Characteristics The genus is characterised by members who are: Gram-negative (like all Proteobacteria) ovoid to rod-shaped cells 0.6–1.6 × 1.0–4.0 µm motile by polar flagella, or nonmotile non-sporeformers aerobic oxidase and catalase positive are incapable of photosynthetic growth bacteriochlorophyll a is absent major quinone is ubiquinone 10 mol% G+C of the DNA is 55–59 member of the family Rhodobacteraceae, which is phenotypically, metabolically, ecologically diverse and defined based on 16S sequences data Phylogenetically it is very close to the genus Silicibacter, but the two remain separate species due to phenotypic differences — two species for which this is problematic are Ruegeria lacuscaerulensis and Ruegeria pomeroyi. Two species that have been removed from the genus are Marinovum algicola (Ruegeria algicola) and Thalassobius gelatinovorus (Ruegeria gelatinovora).[and refs therein] Small non-coding RNAs Highly abundant bacterial small RNAs have been shown to be present in the bacteria subjected to chronic nutrient limitation. In Ruegeria pomeroyi RNAseq analysis identified 99 putative sRNAs. The bacterial sRNAs regulatory mechanisms are typically based on direct RNA-RNA interaction with a target mRNA. The target gene groups identified by Rivers et al. were genes involved in transport, genes mediating cell-cell interactions, signal transduction and transcriptional regulation. References Further reading Scientific journals Scientific books Scientific databases External links Rhodobacteraceae Bacteria genera