Skip to main content
PMC home page
Biochemical Journal logoLink to Biochemical Journal
. 1988 Jul 15;253(2):517–522. doi: 10.1042/bj2530517

Theoretical treatment of tight-binding inhibition of an enzyme. Ribonuclease inhibitor as special case.

J M Fominaya 1, J M García-Segura 1, M Ferreras 1, J G Gavilanes 1
PMCID: PMC1149328  PMID: 3178726

Abstract

A general treatment of very tight-binding inhibition is described. It was applied to purified endogenous RNAase inhibitor from rat testis. This treatment discriminates among the different types of inhibition and allows for calculation of the inhibition parameters. When very tight-binding inhibitions are studied at similar molar concentrations of both enzyme and inhibitor, a further approach is required. This is also described and applied to the RNAase inhibitor. A Ki value of 3.2 x 10(-12) M was found for this inhibitor protein. On the basis of this result, it was considered inappropriate to classify this type of inhibitor in terms of competitive or non-competitive, as has been done for such inhibitors so far. Functional consequences of this analysis are discussed for the RNAase-RNAase inhibitor system.

Full text

PDF
517

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Baici A. The specific velocity plot. A graphical method for determining inhibition parameters for both linear and hyperbolic enzyme inhibitors. Eur J Biochem. 1981 Sep;119(1):9–14. doi: 10.1111/j.1432-1033.1981.tb05570.x. [DOI] [PubMed] [Google Scholar]
  2. Blackburn P., Gavilanes J. G. Identification of lysine residues in the binding domain of ribonuclease A for the RNase inhibitor from human placenta. J Biol Chem. 1982 Jan 10;257(1):316–321. [PubMed] [Google Scholar]
  3. Blackburn P., Gavilanes J. G. The role of lysine-41 of ribonuclease A in the interaction with RNase inhibitor from human placenta. J Biol Chem. 1980 Nov 25;255(22):10959–10965. [PubMed] [Google Scholar]
  4. Blackburn P., Jailkhani B. L. Ribonuclease inhibitor from human placenta: interaction with derivatives of ribonuclease A. J Biol Chem. 1979 Dec 25;254(24):12488–12493. [PubMed] [Google Scholar]
  5. Blackburn P., Wilson G., Moore S. Ribonuclease inhibitor from human placenta. Purification and properties. J Biol Chem. 1977 Aug 25;252(16):5904–5910. [PubMed] [Google Scholar]
  6. Burton L. E., Blackburn P., Moore S. Ribonuclease inhibitor from bovine brain. Int J Pept Protein Res. 1980 Nov;16(5):359–364. doi: 10.1111/j.1399-3011.1980.tb02959.x. [DOI] [PubMed] [Google Scholar]
  7. Burton L. E., Fucci N. P. Ribonuclease inhibitors from the livers of five mammalian species. Int J Pept Protein Res. 1982 Apr;19(4):372–379. doi: 10.1111/j.1399-3011.1982.tb02618.x. [DOI] [PubMed] [Google Scholar]
  8. DIXON M. The determination of enzyme inhibitor constants. Biochem J. 1953 Aug;55(1):170–171. doi: 10.1042/bj0550170. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Dixon M. The graphical determination of K m and K i . Biochem J. 1972 Aug;129(1):197–202. doi: 10.1042/bj1290197. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. García-Segura J. M., Orozco M. M., Fominaya J. M., Gavilanes J. G. Purification, molecular and enzymic characterization of an acid RNase from the insect Ceratitis capitata. Eur J Biochem. 1986 Jul 15;158(2):367–372. doi: 10.1111/j.1432-1033.1986.tb09760.x. [DOI] [PubMed] [Google Scholar]
  11. Henderson P. J. A linear equation that describes the steady-state kinetics of enzymes and subcellular particles interacting with tightly bound inhibitors. Biochem J. 1972 Apr;127(2):321–333. doi: 10.1042/bj1270321. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Morrison J. F. Kinetics of the reversible inhibition of enzyme-catalysed reactions by tight-binding inhibitors. Biochim Biophys Acta. 1969;185(2):269–286. doi: 10.1016/0005-2744(69)90420-3. [DOI] [PubMed] [Google Scholar]
  13. Shapiro R., Vallee B. L. Human placental ribonuclease inhibitor abolishes both angiogenic and ribonucleolytic activities of angiogenin. Proc Natl Acad Sci U S A. 1987 Apr;84(8):2238–2241. doi: 10.1073/pnas.84.8.2238. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Turner P. M., Lerea K. M., Kull F. J. The ribonuclease inhibitors from porcine thyroid and liver are slow, tight-binding inhibitors of bovine pancreatic ribonuclease A. Biochem Biophys Res Commun. 1983 Aug 12;114(3):1154–1160. doi: 10.1016/0006-291x(83)90683-6. [DOI] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES