THIOSULFATE AS A METABOLIC PRODUCT - THE BACTERIAL FERMENTATION OF TAURINE

Thiosulfate (S2O32-) is a natural product that is widely utilized in n atural ecosystems as an electron sink or as an electron donor. However , the major biological source(s) of this thiosulfate is unknown. We pr esent the first report that taurine (2-aminoethanesulfonate), the majo r mammalian solute, is subject to fermentation. This bacterial ferment ation was found to be catalyzed by a new isolate, strain GKNTAU, a str ictly anaerobic, gram-positive, motile rod that formed subterminal spo res. Thiosulfate was a quantitative fermentation product. The other fe rmentation products were ammonia and acetate, and all could be formed by cell-free extracts.