Mutational analysis of the important amino acids in the catalytic triad of serine proteases showed that replacing Asp102 or modifying His57 with amethyl group decreased the reaction rate about 5000-fold. However,mutating Ser195 decreased the reaction rate a millionfold. Discuss why mutating Ser had a larger impact than the other members of the catalytic triad.

Mutational analysis of the important amino acids in the catalytic triad of serine proteases showed that replacing Asp102 or modifying His57 with amethyl group decreased the reaction rate about 5000-fold. However,mutating Ser195 decreased the reaction rate a millionfold. Discuss why mutating Ser had a larger impact than the other members of the catalytic triad.

Biochemistry

6th Edition

ISBN:9781305577206

Author:Reginald H. Garrett, Charles M. Grisham

Publisher:Reginald H. Garrett, Charles M. Grisham

Chapter26: Synthesis And Degradation Of Nucleotides

Section: Chapter Questions

Problem 14P: The Energy Cost of dTTP Synthesis (Integrates with Chapter 20.) Starting from HCO3, glutamine,...

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