| 摘 要： | The reactivation of delipidated cytochrome oxidase depends on the reformation of "an-nular lipids", which is tightly bounded to the enzyme molecule. In the restoration of oxidase activity, the efficiencies of phospholipids with differentpolar head groups decrease in this order: PS>DPG>PI>PA>PG>PC, PE and inthe case of phosphatidyleholines with differentt acyl chain the order is: DOPC>LPC>PC>DPPC, DSPC. Therefore both the polar head group and the acyl ehain of phospholipidsmust be considered in the reactivatioll process. The existence and fhe specificity of "anuular lipids' obviously influence the incorpora-tion of cytochrome oxidase into liposomes. When acidic phospholipids are used as "annularlipids", the effectiveness of reconstitution decreases in this order: PI>PS>DPG>PA,PG. Divalent metallic cations would facilitate the cytochrome oxidase reconstitution, but theireffects depend on the composition of "annular lipids". Using dialysis method Ca~(2 ) andMg~(2 ) could facilitate the incorporation into liposomes of tlle enzymes having PS or DOPCas their "boundary lipids". A comparison between the effects of different metallic cations on incorporation of cyto-cbrome oxidase also shows that, with PI as "annulay lipids", the effectiveness of differentcations on incorporation by incubation method decreases in this order: Ca~(2 )>Mg~(2 )>Mn~(2 ),Sr~(2 )>La~(3 ). Apparently, the effect of metallic cations on incorporntion cannot be inter-preted by considering only the neutralization of the negative charged groups on membraneprotein and lipids.
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