Characterization of extracellular RNAs produced by the marine photosynthetic bacterium Rhodovulum sulfidophilum

The marine photosynthetic bacterium Rhodovulum sulfidophilum produces extracellular nucleic acids that are involved in its flocculation. These were found to be produced concomitantly with cell growth. The RNA fraction of these extracellular nucleic acids was subjected to cDNA analysis by applying a micro RNA cloning method and found to contain mainly fully mature-sized tRNAs and fragments of 16S and 23S rRNAs. Analyses of modified bases and genes of the RNAs revealed no structural difference between the intracellular and extracellular RNAs. This is the first report of structural analyses of bacterial extracellular RNAs.