NUTRITIONAL CHARACTERISTICS OF A BUTYRIVIBRIO

Abstract

Certain nutritional characteristics of an unspecified member of the genus Butyrivibrio isolated from the bovine rumen were investigated using chemically defined media. Maximum growth response to biotin, folic acid, and pyridoxal hydro-chloride was observed at approximately 0.005, 0.007, and 0.12 [mu]g per ml, respectively. The other B-vitamins tested were non-essential. Carbon dioxide was essential at concentrations in excess of 0.02 [image]. No evidence of a requirement for either purines or pyrimidines was seen. The nutritionally critical amino acids included histidine, isoleucine, methionine, lysine, cysteine, leucine, tyrosine, and valine. The requirement for amino acids was, in general, only partial and large amounts of ammonia were assimilated. Rumen fluid and certain other crude preparations were found to contain a substance (or several substances) which was strongly stimulatory to growth. None of 68 compounds commonly stimulatory to microbial growth could replace the active principle in rumen fluid.