Anaerobic oxidation of fatty acids by Clostridium bryantii sp. nov., a sporeforming, obligately syntrophic bacterium

From marine and freshwater mud samples strictly anaerobic, Gram-positive, sporeforming bacteria were isolated which oxidized fatty acids in obligately syntrophic association with H-utilizing bacteria. Even-numbered fatty acids with up to 10 carbon atoms were degraded to acetate and H, odd-numbered fatty acids with up to 11 carbon atoms including 2-methylbutyrate were degraded to acetate, propionate and H. Neither fumarate, sulfate, thiosulfate, sullur, nor nitrate were reduced. A marine isolate, strain CuCal, is described as type strain of a new species, sp. nov.