RT Journal Article SR Electronic(1) A1 STRATFORD, MALCOLM A1 ROSE, ANTHONY H.YR 1986 T1 Transport of Sulphur Dioxide by Saccharomyces cerevisiae JF Microbiology, VO 132 IS 1 SP 1 OP 6 DO https://doi.org/10.1099/00221287-132-1-1 PB Microbiology Society, SN 1465-2080, AB SUMMARY: Accumulation of label from a suspension (pH 4∙0) of Saccharomyces cerevisiae containing 100 mm-glucose and 1 mm-[35S]sulphite was initially rapid. Net accumulation ceased after 5 min, but at this time [35S]sulphite was still transported by organisms, and could be washed out to an extent that depended on the wash volume. Pre-incubation in the absence of glucose, and omitting glucose from the reaction mixture, had no effect on initial velocity of sulphite accumulation, although it decreased the total amount accumulated. Initial velocity of accumulation was also unchanged when organisms were pre-incubated in the presence of 2-deoxy-d-glucose and this inhibitor was included in the reaction mixture. Initial velocity of sulphite accumulation decreased logarithmically as the pH value of the suspension was increased from 3∙0 to 5∙0; the decrease closely paralleled the decline in concentration of molecular SO2 over this pH range. Woolf–Hofstee plots for accumulation of SO2, at pH 3∙0 or 4∙0, gave near-vertical plots. Raising the temperature from 19 to 39°C increased the initial velocity of SO2 accumulation. The initial velocity of transport was not affected by pretreatment of organisms with carbonyl cyanide m-chlorophenylhydrazone, DNP or iodoacetamide but pretreatment with 20 mm-uranyl nitrate increased the initial velocity almost threefold. It is concluded that SO2 is transported into S. cerevisiae by simple diffusion., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-132-1-1