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Literature DB >> 12913

The intrinsic pKa-values of functional groups in enzymes: improper deductions from the pH-dependence of steady-state parameters.

Abstract

The assumptions implicit in the deductions made from the pH-dependence of rate measurements of enzyme-catalyzed reactions are summarized, and the limitations of such determinations are discussed nonalgebraically. The following types of pH-profile are considered (in order of increasing utility): pH-"activity" curves at fixed [S] o;pH-dependences of kcat, Km, kcat/Km, and Ki; pH-dependences of kmodification (by specific reagents) and of competitive labeling (by nonspecific reagents); pH-dependences of elementary steps; and the direct observation of a titrating group.

Mesh：

Substances：
Enzymes

Year: 1976 PMID： 12913 DOI： 10.3109/10409237609105457

Source DB: PubMed Journal: CRC Crit Rev Biochem ISSN： 0045-6411

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Cited

26 in total

1. Thermodynamic linkage between the binding of protons and inhibitors to HIV-1 protease.

Authors: J Trylska; J Antosiewicz; M Geller; C N Hodge; R M Klabe; M S Head; M K Gilson
Journal: Protein Sci Date: 1999-01 Impact factor: 6.725

2. Evidence for proton transfer in the rate-limiting step of a fast-cleaving Varkud satellite ribozyme.

Authors: M Duane Smith; Richard A Collins
Journal: Proc Natl Acad Sci U S A Date: 2007-03-26 Impact factor: 11.205

3. pH-activity curves for enzyme-catalysed reactions in which the hydron is a product or reactant.

Authors: H B Dixon; K Brocklehurst; K F Tipton
Journal: Biochem J Date: 1987-12-01 Impact factor: 3.857

4. Rapid assembly of a library of lipophilic iminosugars via the thiol-ene reaction yields promising pharmacological chaperones for the treatment of Gaucher disease.

Authors: Ethan D Goddard-Borger; Michael B Tropak; Sayuri Yonekawa; Christina Tysoe; Don J Mahuran; Stephen G Withers
Journal: J Med Chem Date: 2012-03-06 Impact factor: 7.446

5. Benzofuroxan as a thiol-specific reactivity probe. Kinetics of its reactions with papain, ficin, bromelain and low-molecular-weight thiols.

Authors: M Shipton; K Brocklehurst
Journal: Biochem J Date: 1977-12-01 Impact factor: 3.857

The intrinsic pKa-values of functional groups in enzymes: improper deductions from the pH-dependence of steady-state parameters.

1. Thermodynamic linkage between the binding of protons and inhibitors to HIV-1 protease.

2. Evidence for proton transfer in the rate-limiting step of a fast-cleaving Varkud satellite ribozyme.

3. pH-activity curves for enzyme-catalysed reactions in which the hydron is a product or reactant.

4. Rapid assembly of a library of lipophilic iminosugars via the thiol-ene reaction yields promising pharmacological chaperones for the treatment of Gaucher disease.

5. Benzofuroxan as a thiol-specific reactivity probe. Kinetics of its reactions with papain, ficin, bromelain and low-molecular-weight thiols.

6. The pH-dependence of second-order rate constants of enzyme modification may provide free-reactant pKa values.

7. Sulphate-activated phosphorylase b: the pH-dependence of catalytic activity.

8. Tautomerism, acid-base equilibria, and H-bonding of the six histidines in subtilisin BPN' by NMR.

Review 9. Glycosidase inhibition: assessing mimicry of the transition state.

10. The pKa of the catalytic histidine residue of chloramphenicol acetyltransferase.