Protein E can bind to two different proteins, S and I. The binding reactions are described
by the following equations and values:
E + S->ES Keq for ES = 10
E + I->EI Keq for EI = 2
(a) E binds I more tightly than S.
(b) When S is present in excess, no I molecules will bind to E.
(c) The binding energy of the ES interaction is greater than that of the EI interaction.
(d) Changing an amino acid on the binding surface of I from a basic amino acid to an acidic one will probably make the free energy of association with E more negative.
Answer: C
by the following equations and values:
E + S->ES Keq for ES = 10
E + I->EI Keq for EI = 2
Given the equilibrium constant values, which one of the following statements is true?
(a) E binds I more tightly than S.
(b) When S is present in excess, no I molecules will bind to E.
(c) The binding energy of the ES interaction is greater than that of the EI interaction.
(d) Changing an amino acid on the binding surface of I from a basic amino acid to an acidic one will probably make the free energy of association with E more negative.
Answer: C