Kotyk A
Department of Membrane Transport, Czechoslovak Academy of Sciences, Prague.
Folia Microbiol (Praha). 1992;37(6):401-3. doi: 10.1007/BF02899896.
The transport of inorganic phosphate anions into yeast cells (after preincubation with glucose, fructose or another metabolizable sugar, and in the presence of glucose) shows two kinetic components with half-saturation constants of 40 mumol/L and 2.4 mmol/L. The uptake was strikingly stimulated by 2-deoxy-D-glucose (2-dGlc) at lower concentrations but inhibited above 100 mmol/L. A similar stimulation was caused by adenine (0.01-1 mmol/L) and a very small one by uracil and inorganic sulfate. It is suggested that either a phosphorylation reaction accompanies the transport (2-dGlc) or that some compounds stimulate the H(+)-ATPase more than inorganic phosphate itself and thus increase its rate of transport.
无机磷酸阴离子进入酵母细胞的过程(在与葡萄糖、果糖或其他可代谢糖预孵育后,且存在葡萄糖的情况下)呈现出两个动力学成分,其半饱和常数分别为40 μmol/L和2.4 mmol/L。在较低浓度下,2-脱氧-D-葡萄糖(2-dGlc)能显著刺激摄取,但在浓度高于100 mmol/L时则起抑制作用。腺嘌呤(0.01 - 1 mmol/L)也会引起类似的刺激,而尿嘧啶和无机硫酸盐引起的刺激则非常小。有人提出,要么是磷酸化反应伴随转运过程(2-dGlc)发生,要么是某些化合物比无机磷酸本身更能刺激H(+)-ATP酶,从而提高其转运速率。