Benga G, Popescu O, Borza V, Pop V I, Muresan A, Mocsy I, Brain A, Wrigglesworth J M
Eur J Cell Biol. 1986 Aug;41(2):252-62.
The water permeability of human erythrocytes has been monitored by nuclear magnetic resonance (NMR) before and after treatment of the cells with various sulfhydryl reagents. Preincubation of the cells with N-ethylmaleimide (NEM), a non-inhibitory sulfhydryl reagent, results in a faster and more sensitive inhibition of water exchange by mercurials. The inhibition of water exchange by p-chloromercuribenzene sulfonate (PCMBS) was maximal at a binding of approximately 10 nmol PCMBS per mg protein when non-specific sulfhydryl groups are blocked by NEM. Inhibition by PCMBS has been correlated with the binding of 203Hg to erythrocyte membrane proteins. A significant binding of label to band 3 and the polypeptides in band 4.5 occurs, with approximately 1 mol of mercurial bound per mol of protein. Inhibition of water transport by sulfhydryl reagents does not induce major morphological changes in the cells as assessed by freeze-fracture and scanning electron microscopy.
在用各种巯基试剂处理细胞之前和之后，通过核磁共振（NMR）监测了人类红细胞的水渗透性。用非抑制性巯基试剂N-乙基马来酰亚胺（NEM）对细胞进行预孵育，会导致汞剂对水交换的抑制作用更快且更敏感。当非特异性巯基被NEM阻断时，对氯汞苯磺酸盐（PCMBS）对水交换的抑制作用在每毫克蛋白质结合约10 nmol PCMBS时达到最大。PCMBS的抑制作用与203Hg与红细胞膜蛋白的结合相关。标记物与带3和带4.5中的多肽有显著结合，每摩尔蛋白质约结合1摩尔汞剂。通过冷冻断裂和扫描电子显微镜评估，巯基试剂对水运输的抑制不会在细胞中引起主要的形态变化。
