An antibody (Ab) can bind to its antigen binding site (B) with a high affinity (large negative AG°). The antibody and the antigen are mixed at low concentrations and allowed to reach equilibrium. The concentrations measured are [Ab] = 1 nM, [B] = 40 nM, and [Ab-B] = 30 nM, for the equilibrium Ab +B= Ab-B. A. What is the equilibrium constant (association constant), Ka, in M1? B. What is Kd = 1/Ka in nM? C. What is AG° in kgT/molecule? Use the equation AG° = –kgTln(Ka) = kgTln(Ka)

An antibody (Ab) can bind to its antigen binding site (B) with a high affinity (large negative AG°). The antibody and the antigen are mixed at low concentrations and allowed to reach equilibrium. The concentrations measured are [Ab] = 1 nM, [B] = 40 nM, and [Ab-B] = 30 nM, for the equilibrium Ab +B= Ab-B. A. What is the equilibrium constant (association constant), Ka, in M1? B. What is Kd = 1/Ka in nM? C. What is AG° in kgT/molecule? Use the equation AG° = –kgTln(Ka) = kgTln(Ka)

Introduction to General, Organic and Biochemistry

11th Edition

ISBN:9781285869759

Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar Torres

Publisher:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar Torres

Chapter23: Enzymes

Section: Chapter Questions

Problem 23.14P

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