ISOLATION OF AN ACETICLASTIC STRAIN OF METHANOSARCINA-SICILIAE FROM MARINE CANYON SEDIMENTS AND EMENDATION OF THE SPECIES DESCRIPTION FOR METHANOSARCINA-SICILIAE

A newly described strain of the genus Methanosarcina was isolated from submarine canyon sediments and is shown by comparative sequence analy ses of 16S ribosomal DNA and the gene encoding methyl coenzyme M reduc tase, mcrI, to be a strain of Methanosarcina siciliae. Morphological a nd physiological characteristics are described. In contrast to the two previously described strains that grow exclusively on methanol, methy lamines, and dimethylsulfide, M. siciliae C2J is also capable of growt h on and methanogenesis from acetate. We propose that the species desc ription for M. siciliac be amended to include aceticlastic strains.