56.
A chemically defined medium for
Veillonella parvula and
V. alcalescens is described. Some nutritional aspects of the two strains used were examined: the optimum concentration of reducing agents, the requirement for amino acids, diamines, vitamins and other growth factors, and the conditions needed for well balanced nutrition.No specific requirements for single amino acids were observed. A combination of l-cysteine,
dl-aspartic acid, l-glutamic acid, l-serine and l-tyrosine, promoted growth. In
V. alcalescens, serine could substitute both arginine and tryptophan (or histidine). No growth was obtained with ammonium salts as the sole N source.Decarboxylation of l-ornithine, l-lysine and l-arginine was not demonstrated in the
Veillonella parvula strain, which required putrescine or cadaverine for growth. Spermine, spermidine, l-lysine, l-ornithine and l-arginine, could not substitute putrescine in
Veillonella parvula. Veillonella alcalescens, which does not require putrescine in the medium, was able to decarboxylate l-ornithine while forming putrescine.
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