RT Journal Article SR Electronic(1) A1 Ahmad, Fazal A1 Rose, A. H. A1 Garg, N. K.YR 1961 T1 Effect of Biotin Deficiency on the Synthesis of Nucleic Acids and Protein by Saccharomyces cerevisiae JF Microbiology, VO 24 IS 1 SP 69 OP 80 DO https://doi.org/10.1099/00221287-24-1-69 PB Microbiology Society, SN 1465-2080, AB SUMMARY A strain of Saccharomyces cerevisiae, grown in a medium containing a suboptimal concentration (0·4 × 10−10m) of biotin, was shown to contain less deoxyribonucleic acid (DNA), ribonucleic acid (RNA) and protein but, during the early stages of growth, increased concentrations of acid-soluble ultraviolet (u.v.)-absorbing substances, as compared with the same organism grown in the presence of an optimal concentration (8·0 × 10−10 m) of biotin. The concentration of acid-soluble u.v.-absorbing substances in the biotin-deficient yeast was higher, irrespective of the nature of the extracting acid (0·2v-perchloric acid, 5% (w/v) and 10% (w/v) trichloroacetic acid, or 5 % (v/v) n-butanol in m/15 KH2PO4). Raising the temperature of extraction from 3° to 21° or 30° had little or no effect on the amounts of these u.v.-absorbing substances extracted. Analyses of the nucleotides and nucleo- bases in the yeast RNA showed these to have a ratio of purine:pyrimidine bases of 1·00–1·15, with the exception of the RNA from 5-day cultures of biotin-deficient yeast which had a slightly but consistently higher ratio. The significance of these results is discussed in relation to the metabolic function of biotin., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-24-1-69