ABSTRACT
Objective:To predict the secondary structure and B cell epitope of human decay accelerating factor Methods:The accuracy of two secondary structure prediction methods,Chou & Fasman and PHDsec,was compared,and then human DAF secondary structure was analyzed by PHDsec Hydrophilicity scores and solvent accessibility of DAF SCR1 4 were obtained by methods of Hopp & Woods and PHDacc respectively Combined with the secondary structure of DAF,the B cell epitopes in DAF were predicted Results:PHDsec which use multiple sequence alignment,achieve a better prediction accuracy There is no alpha helix in SCR1 4 of human DAF but only beta sheet and loop segments; The computer predicted most possible epitope in DAF localize within amino acid residues Pro73 Val79?Arg130 Leu139 and Glu156 Cys163 Conclusion:These results will be useful in estimate of the epitope and activity sites localized within human DAF