Development of a defined medium forClostridium scatologenesATCC 25775

Abstract

To develop a defined medium for Clostridium scatologenes ATCC 25775, which produces the malodorants 3-methylindole (skatole) and 4-methylphenol (p-cresol). Clostridium scatologenes was cultured in anaerobic broth medium (pH 6.3) at 37 degrees C containing ammonia, minerals and a commercial vitamin solution. Data indicate alpha-ketoglutarate, L-glutamate or L-glutamine is a required nutrient that can also serve as a primary carbon and energy source. When cultured in defined medium containing glutamate; glucose, fructose and betaine served as primary carbon and energy sources. L-Tryptophan, L-tyrosine, sorbitol and indole acetic acid did not enhance growth. In the absence of tryptophan, cells produced indole when grown using glucose or fructose. 4-Methylphenol was produced when growing cells were supplied with tyrosine. When supplied with tryptophan, 3-methylindole was produced by glucose- or fructose-growing cells but not from glutamate-growing cells. Cells grown in the presence of pyruvate produced indole, 3-methylindole and 4-methylphenol. Clostridium scatologenes requires alpha-ketoglutarate, L-glutamate, or L-glutamine for growth in defined medium. Cells produce indole when glucose or fructose is included in defined medium. The development of a defined medium will assist in physiology studies and genetic analysis of this strain.