oceanococcus oceanococcus oceanococcus is a gram-negative genus of bacteria from the family of ectothiorhodospiraceae with one known species (oceanococcus atlanticus). oceanococcus atlanticus has been isolated from deep sea sediments from the atlantic ocean. oceanococcus scientific classification domain: bacteria phylum: pseudomonadota class: gammaproteobacteria order: chromatiales family: ectothiorhodospiraceae genus: oceanococcusli et al. 2014 type species oceanococcus atlanticus species o. atlanticus synonyms maricoccus