Michael N.G. James
Michael N.G. James (University of Alberta, Edmonton, Canada)
Resume: Professor Michael James, FRS, FRSC, received a B.Sc. and an M.Sc. at the University of Manitoba. He then studied for his D. Phil. degree at Oxford University under the supervision of Professor Dorothy Hodgkin, OM, FRS, Nobel Laureate. He returned to Canada in 1967 and started as Assistant Professor in the Department of Biochemistry at the University of Alberta. His laboratory was the first lab to determine the 3D structure of a protein molecule in Canada in 1975. The early period of research in his lab concentrated on proteolytic enzymes from bacteria, fungi and viruses. More recently research in his lab has been on glycosyl hydrolases.
What can avian ovomucoids teach us about Serine peptidase specificity?
My favourite peptidases are the serine peptidases of the chymotrypsin family. The avian ovomucoids are small protein inhibitors of these peptidases. Depending upon the nature of the P1 residue of the inhibitor, association constants can range from 104 to 1011. I will discuss the cases of the carboxyl groups of the Asp and Glu sidechains having their pKa’s raised by ~4.5 pH units. The textbooks say that the S1 binding pocket of porcine elastase will accept only small P1 side chains such as Gly, Ala, Val and Ser. What happens when the P1 residues are Leu and Phe?
