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Yeast S. cerevisiae sometimes inhabit in the environment, acidity of which is connected with significant L-malate concentrations. For example, such situation develops during manufacture of dry grape wines. Low-active transporter-receptor of inorganic phosphate with pH optimum in alkaline area was characterized recently in plasma membrane of this yeast. Earlier we have found out low-active (13.8 ± 0.4 nmol/min/1 mg of dry weight) plasma membrane dicarboxylate transporter sensitive to 2-undecyl malonate. It has been difficult to study because of its low activity and special properties. This S. cerevisiae transporter has alkaline pH-optimum and transports succinate more effectively, than citrate. After 15-18h of aerobic preincubation at 0°C of yeast cells, external Land D-malate stimulates respiration and 2-undecyl malonate inhibits oxidation of both substrates. However the malate oxidation becomes negligible after 24-26h of such preincubation. These stereoisomers competitively inhibits the succinate oxidation and transplasmalemmal transport of this dicarboxylate into cells limits respiration at that. Change of the incubation medium pH value from 5.5 to 6.5 causes growth of the ratio value of IC₅₀ (one of the parameters of inhibition) of D-malate and IC₅₀ of L-malate from 1.0 to 6.4. At the same time succinate dianion affinity varies a little bit. Such selective regulation of transplasmalemmal dicarboxylate transporter affinity may indicate that this carrier is a malate receptor and a probable sensor of extracellular pH.