Abstract：haseolus coccineus var.rubonanous lectin(PCL) was modified with various reagents to determine the amino acid residues that are involved at its carbohydrate binding site.The PCL molecule had eight Trp residues as demonstrated by modification with N bromosuccinimide in 8 M urea.In native state PCL had only four exposed Trp residues,modification of which led to complete loss of the hemagglutinating activity of the protein.CD spectra of PCL indicated that modification of Trp residues did not change the secondary structure of PCL.Modification of Tyr,Arg and His residues and free amino and carboxyl groups did not affect the hemagglutinating activity of PCL.Sulfhydryl groups were also not essential for the activity;but reduction of disulfide bonds in the PCL molecule or CNBr degradation of PCL into two fragments rendered the protein inactive.These two findings indicated the importance of the overall structure of the protein for its hemagglutinating activity.
施炜星,孙册. 红花菜豆(矮生红花变种)凝集素分子的色氨酸残基修饰与其活性的关系[J]. 中国生物化学与分子生物学报, 1997, 13(04): 438-443.
Shi Wei Xing Sun Ce. Tryptophan modified Phaseolus coccineus var. rubonanous Lectin in Relation to its Activity. Chinese Journal of Biochemistry and Molecular Biol, 1997, 13(04): 438-443.
