Relative acetate- and MCA- uptake activities of MBA4 grown in various substrates. MBA4 was grown in minimal medium containing acetate, MCA, MBA, propionate, 2MCPA, butyrate, or valerate. Uptakes of 50 μM of [2-14C]acetate (A) or [2-14C]MCA (B) were assayed for a period of 1 min. Data shown are the means of three independent experiments, and the error bars represent the standard deviations. (A) The acetate-uptake rate of acetate-grown cells was set as 100%, and acetate-uptake rates of cells grown in other substrates were determined and shown as percentages. (B) The MCA-uptake rate of MCA-grown cells was set as 100%, and MCA-uptake rates of cells grown in other substrates were determined and shown as percentages.