Shaklai N, Benitez L, Ranney H M
Am J Physiol. 1978 Jan;234(1):C36-40. doi: 10.1152/ajpcell.1978.234.1.C36.
The relationships between spectrin, a structural protein of the red blood cell (RBC) membrane facing the cytoplasm, and hemoglobin were studied. The oxygen-binding properties of stripped hemoglobin were not altered by the presence of spectrin, but the interaction of hemoglobin with organic phosphates was reduced by the addition of spectrin. The presence of the enzyme glyceraldehyde 3-phosphate dehydrogenase (G3PD), another component of the RBC membrane used as a control, did not change the oxygen affinity of either stripped hemoglobin or of hemoglobin solutions containing phosphates. Binding studies using the gel filtration method at pH 7.3 indicated reversible binding of 2,3-diphosphoglycerate to spectrin. A unit of 220,000 daltons was calculated to have seven binding sites and a binding constant of 1.2 X 10(4) M-1. A mechanism is proposed in which spectrin may facilitate oxygen transport for hemoglobin molecules reaching the membrane.
研究了血影蛋白（一种面向细胞质的红细胞（RBC）膜结构蛋白）与血红蛋白之间的关系。去除其他物质的血红蛋白的氧结合特性不会因血影蛋白的存在而改变，但添加血影蛋白会降低血红蛋白与有机磷酸盐的相互作用。作为对照的红细胞膜的另一种成分——甘油醛3-磷酸脱氢酶（G3PD）的存在，不会改变去除其他物质的血红蛋白或含磷酸盐的血红蛋白溶液的氧亲和力。在pH 7.3条件下使用凝胶过滤法进行的结合研究表明，2,3-二磷酸甘油酸与血影蛋白存在可逆结合。计算得出一个220,000道尔顿的单位有七个结合位点，结合常数为1.2×10⁴ M⁻¹。提出了一种机制，即血影蛋白可能促进到达膜的血红蛋白分子的氧运输。
