镉处理的小麦幼苗类囊体膜的脂质组成

Lipid composition of thylakoid membranes of cadmium treated wheat seedlings.

作者信息

Malik D, Sheoran I S, Singh R

机构信息

Department of Chemistry and Biochemistry, Haryana Agricultural University, Hisar.

出版信息

Indian J Biochem Biophys. 1992 Aug;29(4):350-4.

PMID:1427962

Abstract

Cadmium (200 ppm) applied through the rooting medium to 30-day-old wheat plants decreased chlorophyll content, net CO2 exchanges and PSII activity by 34, 54 and 43% respectively. Thylakoid total lipids, total glycolipids, total phospholipids and total neutral lipids decreased by 22, 23, 12 and 25%, respectively, under cadmium treatment. Thylakoid membrane glycolipids had three major constituents, viz. monogalactosyl diacylglycerol, digalactosyl diacylglycerol and sulphoquinovosyl diacylglycerol. Monogalactosyl diacylglycerol and digalactosyl diacylglycerol contents decreased by 32 and 27%, respectively, under cadmium. Cadmium application also decreased the concentration of phosphatidyl glycerol and phosphatidyl choline to the extent of about 57 and 31%, respectively. On the other hand, phosphatidic acid and free fatty acids content showed an increase. These compositional changes in thylakoid membranes might be responsible for reduced PSII activity and rate of photosynthesis as observed under cadmium treatment.

摘要

通过生根培养基向30日龄小麦植株施加200 ppm镉，分别使叶绿素含量、净二氧化碳交换量和PSII活性降低了34%、54%和43%。在镉处理下，类囊体总脂质、总糖脂、总磷脂和总中性脂质分别降低了22%、23%、12%和25%。类囊体膜糖脂有三种主要成分，即单半乳糖基二酰基甘油、二半乳糖基二酰基甘油和磺基喹喔基二酰基甘油。在镉处理下，单半乳糖基二酰基甘油和二半乳糖基二酰基甘油含量分别降低了32%和27%。施加镉还使磷脂酰甘油和磷脂酰胆碱的浓度分别降低了约57%和31%。另一方面，磷脂酸和游离脂肪酸含量有所增加。类囊体膜的这些成分变化可能是镉处理下观察到的PSII活性和光合作用速率降低的原因。