AN INVESTIGATION OF CONFIGURATION OF ERYTHROCYTE MEMBRANE PROTEINS WITH MALEIMIDE SPIN LABELS DURING BLOOD PRESERVATION
用马来酰亚胺自旋标记研究库存血红细胞膜蛋白质构象

Two maleimide spin labels, malcimide I and maleimide V, were used to investigate the dynamic changes of the conf ipura t ion and sulfhydryl binding sites of erythrocyte membranc protein- within a 35-day period of ACD-B blood preserved. The results showed: during the preservation period, the S/W ratio ealculated from ESR spectra of maleimide I-labelled erythrocytes decreased rapidly to a lower level; the rotational eorrtlation time (t,.) inferred from ESR spectra of maleimide V-lahelled erythrocytes decreased rapidly in the first week but increased slowly to the initial level in the later stage. The decrease of S /W ratio demonstrated configuration changes of erythrocyte membrane proteins. The changes of rotational correlation time might reflect that the micro-viscosity in the superficial aqueous portion around the membrane proteins,perhaps including the adjacent superficial lipid environment ,undcrwent a bipha-sic change, i.e, decreased rapidly then increased slowly during preservation.