Ohnishi J, Kanai R
Department of Biochemistry, Faculty of Science, Saitama University, Urawa, Japan.
FEBS Lett. 1990 Aug 20;269(1):122-4. doi: 10.1016/0014-5793(90)81134-a.
A sudden pH decrease (pH jump) of the medium enhanced pyruvate uptake in the dark in mesophyll chloroplasts (MCp) of Zea mays and Sorghum bicolor, NADP-malic enzyme type C4 plants, while it was reported that a Na+ jump enhanced pyruvate uptake in MCp of P. miliaceum, a NAD-malic enzyme type [(1987) FEBS Lett. 219, 347]. The enhancement effect of the pH jump decayed completely in 5 min and the decay was accelerated by proton gradient-collapsing reagents. The results suggest that active pyruvate uptake into MCp of NADP-malic enzyme type C4 species is primarily driven by the proton gradient across the envelope.
介质pH值突然下降（pH跃变）增强了玉米和双色高粱（NADP - 苹果酸酶型C4植物）叶肉叶绿体（MCp）在黑暗中对丙酮酸的吸收，而据报道，Na +跃变增强了黍（NAD - 苹果酸酶型）叶肉叶绿体对丙酮酸的吸收[(1987) FEBS Lett. 219, 347]。pH跃变的增强作用在5分钟内完全衰减，质子梯度塌陷试剂加速了这种衰减。结果表明，NADP - 苹果酸酶型C4植物叶肉叶绿体中丙酮酸的主动吸收主要由跨包膜的质子梯度驱动。
