Eddy A A, Hopkins P G
Biochem J. 1985 Oct 15;231(2):291-7. doi: 10.1042/bj2310291.
Strain N.C.Y.C. 193 of Candida utilis was grown aerobically at 30 degrees C with nitrate as limiting nutrient in a chemostat. The washed yeast cells depleted of ATP absorbed up to 5 nmol of nitrate/mg dry wt. of yeast. At pH 4-6, extra protons and nitrate entered the yeast cells together, in a ratio of about 2:1. Charge balance was maintained by an outflow of about 1 equiv. of K+. Nitrate stimulated the uptake of about 1 proton equivalent during glycolysis or aerobic energy metabolism. Studies with 3,3'-dipropylthiadicarbocyanine indicated that the proton-linked absorption of nitrate, amino acids or glucose depolarized the yeast cells. Proton uptake along with lactate led neither to net expulsion of K+ nor to membrane depolarization.
产朊假丝酵母N.C.Y.C. 193菌株在30℃下以硝酸盐作为限制营养物在恒化器中进行好氧培养。耗尽ATP的洗涤酵母细胞每毫克酵母干重吸收高达5 nmol的硝酸盐。在pH 4 - 6时,额外的质子和硝酸盐以约2:1的比例一起进入酵母细胞。通过约1当量K⁺的流出维持电荷平衡。在糖酵解或有氧能量代谢过程中,硝酸盐刺激约1个质子当量的吸收。用3,3'-二丙基硫代二碳菁进行的研究表明,质子偶联的硝酸盐、氨基酸或葡萄糖吸收使酵母细胞去极化。质子与乳酸一起吸收既不会导致K⁺的净排出,也不会导致膜去极化。