PROTON NUCLEAR MAGNETIC RESONANCE AND ELECTRON PARAMAGNETIC RESONANCE INVESTIGATION OF α-α CROSS-LINKED Fe-Co HYBRID HEMOGLOBINS  

作　　者：周玉祥 冯玉萍 YONETANI TAKASHI 

机构地区：[1]Department of Biology and Department of Chemistry,Tsinghua University,Beijing 100084 PRC [2]University of Pennsylvania,USA

出　　处：《Science China Chemistry》1991年第7期850-858,共9页中国科学（化学英文版）

基　　金：This work has been supported by Research Grant HL14508 from the National Heart, Lung and Blood Institute, U.S.A

摘　　要：The following asymmetric α1 99 Lys-α2 99 Lys cross-linked Fe(Ⅱ)-Co(Ⅱ) hybrid hemoglobins (Hbs) were first prepared from derivatives of hemoglobin C (β6 Glu-Lys) and human normal HbA: [α(Co)β(Fe)]A[α(Co)β(Co)]cXL, [α(Fe)β(Co)]A[α(Co)β(Co)]cXL, etc.Their 500 MHz 1H NMR and EPR spectra were measured in order to study the change in their tertiary and quaternary structure under atmosphere of deozy, oxy and carbon monoxide (with or without IHP). From the change of T and R marks in 1H NMR hydrogen bonding region, it is proved that oxygen molecules are first bonded to α(Fe) subunits rather than to β(Fe). The experimental phenomena provided further evidence that intermediate states of ligation are present in addition to T and R state during process of binding of oxygen to Hb. IHP facilitates transformation of T state to R state. The same conclusion can also be drawn from the results of EPR spectra at 77 K.The following asymmetric α1 99 Lys-α2 99 Lys cross-linked Fe(Ⅱ)-Co(Ⅱ) hybrid hemoglobins (Hbs) were first prepared from derivatives of hemoglobin C (β6 Glu-Lys) and human normal HbA: [α(Co)β(Fe)]A[α(Co)β(Co)]cXL, [α(Fe)β(Co)]A[α(Co)β(Co)]cXL, etc.Their 500 MHz 1H NMR and EPR spectra were measured in order to study the change in their tertiary and quaternary structure under atmosphere of deozy, oxy and carbon monoxide (with or without IHP). From the change of T and R marks in 1H NMR hydrogen bonding region, it is proved that oxygen molecules are first bonded to α(Fe) subunits rather than to β(Fe). The experimental phenomena provided further evidence that intermediate states of ligation are present in addition to T and R state during process of binding of oxygen to Hb. IHP facilitates transformation of T state to R state. The same conclusion can also be drawn from the results of EPR spectra at 77 K.

关 键 词：NMR EPR Fe-Co HEMOGLOBIN cross-linkage. 

分 类 号：O6[理学—化学]