摘要Ascorbate peroxidase,a haem protein (EC 1.11.1.11),efficiently scavenges hydro-gen peroxide (H_2O_2) in cytosol and chloroplasts of plants.In this study,a full-length coding sequence of thylakoid-bound ascorbate peroxidase cDNA(TatAPX) was cloned from a drought tolerant wheat cultivar C306.Homology modeling of the TatAPX protein was performed by using the template crystal structure of chloroplastic ascorbate peroxidase from tobacco plant (PDB: 1IYN).The model structure was further refined by molecular mechanics and dynamic methods us-ing various tools such as PROCHECK,ProSA and Verify3D.The predicted model was then tested for docking with H_2O_2,the substrate for TatAPX enzyme.The results revealed that Arg233 and Glu255 in the predicted active site of the enzyme are two important amino acid residues responsible for strong hydrogen bonding affinity with H_2O_2,which might play an important role in scavenging of H_2O_2 from the plant system.