Taxonomic position and seasonal variations in marine neritic environment of some gram-negative antibiotic-producing bacteria.

Six marine bacteria which synthesize macromolecular antibiotics were isolated from neritic waters on the French Mediterranean coast, and their frequency recorded over two successive years. They appeared in relatively large numbers during the period August to December, and can be identified as marine pseudomonads; however, the low guaninecytosine ratio of their DNA, lack of catalase and specific self-inhibition are not compatible with the characteristics of the genus Pseudomonas. Two produced violacein, usually synthesized by bacteria belonging to the genus Chromobacterium. Their taxonomic position is discussed.