Dependence of phosphate transport in yeast of glycolytic substrates

Preincubation of baker's yeast (wild strain, respiration-deficient mutant and a low-phosphorus culture) with glucose, trehalose, and other metabolic sugars increases the subsequent uptake of inorganic phosphate 3-5 times. The Kt is reduced by the preincubation from 3.5 to 1.6 mM. The process involves primarily the production of glycolytic energy sources (suppression by iodoacetamide, no effect of antimycin or dicyclohexylcarbodiimide, negligible effect of ethanol, or respiratory mutation). The low-phosphorus yeast takes up phosphate anions about 1-20 times faster than the high-phosphorus (normal) culture. The stimulation is also accompanied by some (apparently nonessential) protein synthesis and has a halftime of 35 min; its decay has a t0.5 of 12 min but affects only less than one-half of the stimulated capacity.