| Recent reports in the literature suggest a plasmid-encoded mechanism for manganese oxidation by bacteria. To elucidate the role, if any, of plasmids in bacterial manganese oxidation in the marine environment, manganese-oxidizing bacterial strains, isolated from manganese nodules, sediment and seawater samples collected from the Pacific Ocean and Mediterranean Sea were examined for the presence of plasmids and their association with manganese oxidation. 22 of 47 strains of the genera Alcaligenes, Pseudomonas , and Vibrio harbored single plasmids of various sizes even after prolonged storage. The enzymatic oxidation of manganese by some marine bacteria may not be exclusively encoded by plasmid DNA. Functions ascribable to the plasmids remain cryptic,... |
