Abstract
A potentially general kinetic method for the investigation of active-site availability in preparations of macromolecular catalysts was developed. Three kinetic models were considered: (a) the conventional two-step model of enzyme catalysis, where the preparation contains only active catalyst (E(a)) and inert (i.e. non-binding, non-catalytic) material (E(i)); (b) an extension of the conventional model (a) involving only E(a) and E(i), but with non-productive binding to E(a) (in addition to productive binding); (c) a model in which the preparation contains also binding but non-catalytic material (E(b)), predicted to be present in polyclonal catalytic antibody preparations. The method involves comparing the parameters V(max) and K(m) obtained under catalytic conditions where substrate concentrations greatly exceed catalyst concentration with those (klim/obs, the limiting value of the first-order rate constant, k(obs), at saturating concentrations of catalyst; and Kapp/m) for single-turnover kinetics, in which the reverse situation obtains. The active-site contents of systems that adhere to model (a) or extensions that also lack E(b), such as the non-productive binding model (b), may be calculated using [E(a)](T)=V(max)/klim/obs. This was validated by showing that, for alpha-chymotrypsin, identical values of [E(a)](T) were obtained by the kinetic method using Suc-Ala-Ala-Pro-Phe-4-nitroanilide as substrate and the well-known 'all-or-none' spectroscopic assay using N-trans-cinnamoylimidazole as titrant. For systems that contain E(b), such as polyclonal catalytic antibody preparations, V(max)/klim/obs is more complex, but provides an upper limit to [E(a)](T). Use of the kinetic method to investigate PCA 271-22, a polyclonal catalytic antibody preparation obtained from the antiserum of sheep 271 in week 22 of the immunization protocol, established that [E(a)](T) is less than approx. 8% of [IgG], and probably less than approx. 1% of [IgG].
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- BENDER M. L., KEZDY J. MECHANISM OF ACTION OF PROTEOLYTIC ENZYMES. Annu Rev Biochem. 1965;34:49–76. doi: 10.1146/annurev.bi.34.070165.000405. [DOI] [PubMed] [Google Scholar]
- Bender M. L., Begué-Cantón M. L., Blakeley R. L., Brubacher L. J., Feder J., Gunter C. R., Kézdy F. J., Killheffer J. V., Jr, Marshall T. H., Miller C. G. The determination of the concentration of hydrolytic enzyme solutions: alpha-chymotrypsin, trypsin, papain, elastase, subtilisin, and acetylcholinesterase. J Am Chem Soc. 1966 Dec 20;88(24):5890–5913. doi: 10.1021/ja00976a034. [DOI] [PubMed] [Google Scholar]
- ERLANGER B. F., KOKOWSKY N., COHEN W. The preparation and properties of two new chromogenic substrates of trypsin. Arch Biochem Biophys. 1961 Nov;95:271–278. doi: 10.1016/0003-9861(61)90145-x. [DOI] [PubMed] [Google Scholar]
- Eisenthal R., Cornish-Bowden A. The direct linear plot. A new graphical procedure for estimating enzyme kinetic parameters. Biochem J. 1974 Jun;139(3):715–720. doi: 10.1042/bj1390715. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gallacher G., Jackson C. S., Searcey M., Badman G. T., Goel R., Topham C. M., Mellor G. W., Brocklehurst K. A polyclonal antibody preparation with Michaelian catalytic properties. Biochem J. 1991 Nov 1;279(Pt 3):871–881. doi: 10.1042/bj2790871. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gallacher G., Jackson C. S., Searcey M., Goel R., Mellor G. W., Smith C. Z., Brocklehurst K. Catalytic antibody activity elicited by active immunisation. Evidence for natural variation involving preferential stabilization of the transition state. Eur J Biochem. 1993 May 15;214(1):197–207. doi: 10.1111/j.1432-1033.1993.tb17913.x. [DOI] [PubMed] [Google Scholar]
- Gallacher G., Jackson C. S., Topham C. M., Searcey M., Turner B. C., Badman G. T., Brocklehurst K. Polyclonal-antibody-catalysed hydrolysis of an aryl nitrophenyl carbonate. Biochem Soc Trans. 1990 Aug;18(4):600–601. doi: 10.1042/bst0180600. [DOI] [PubMed] [Google Scholar]
- Gallacher G., Searcey M., Jackson C. S., Brocklehurst K. Polyclonal antibody-catalysed amide hydrolysis. Biochem J. 1992 Jun 15;284(Pt 3):675–680. doi: 10.1042/bj2840675. [DOI] [PMC free article] [PubMed] [Google Scholar]
- KEZDY F. J., BENDER M. L. The kinetics of the alpha-chymotrypsin-catalyzed hydrolysis of p-nitrophenyl acetate. Biochemistry. 1962 Nov;1:1097–1106. doi: 10.1021/bi00912a021. [DOI] [PubMed] [Google Scholar]
- Kiefer H. C., Congdon W. I., Scarpa I. S., Klotz I. M. Catalytic accelerations of 10-fold by an enzyme-like synthetic polymer. Proc Natl Acad Sci U S A. 1972 Aug;69(8):2155–2159. doi: 10.1073/pnas.69.8.2155. [DOI] [PMC free article] [PubMed] [Google Scholar]
- OCHOA S., STERN J. R., SCHNEIDER M. C. Enzymatic synthesis of citric acid. II. Crystalline condensing enzyme. J Biol Chem. 1951 Dec;193(2):691–702. [PubMed] [Google Scholar]
- Pike V. W., Wharton C. W., Brocklehurst K., Crook E. M. The synthesis of co-polymers with pendant functional groups arranged in a predetermined geometry as enzyme models [proceedings]. Biochem Soc Trans. 1978;6(1):269–271. doi: 10.1042/bst0060269. [DOI] [PubMed] [Google Scholar]
- Resmini M., Vigna R., Simms C., Barber N. J., Hagi-Pavli E. P., Watts A. B., Verma C., Gallacher G., Brocklehurst K. Characterization of the hydrolytic activity of a polyclonal catalytic antibody preparation by pH-dependence and chemical modification studies: evidence for the involvement of Tyr and Arg side chains as hydrogen-bond donors. Biochem J. 1997 Aug 15;326(Pt 1):279–287. doi: 10.1042/bj3260279. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SCHONBAUM G. R., ZERNER B., BENDER M. L. The spectrophotometric determination of the operational normality of an alpha-chymotrypsin solution. J Biol Chem. 1961 Nov;236:2930–2935. [PubMed] [Google Scholar]
- STADTMAN E. R., NOVELLI G. D., LIPMANN F. Coenzyme A function in and acetyl transfer by the phosphotransacetylase system. J Biol Chem. 1951 Jul;191(1):365–376. [PubMed] [Google Scholar]
- Schultz P. G., Lerner R. A. From molecular diversity to catalysis: lessons from the immune system. Science. 1995 Sep 29;269(5232):1835–1842. doi: 10.1126/science.7569920. [DOI] [PubMed] [Google Scholar]
- Stephens D. B., Wilmore B. H., Iverson B. L. Polyclonal antibodies and catalysis. Bioorg Med Chem. 1994 Jul;2(7):653–658. doi: 10.1016/0968-0896(94)85014-3. [DOI] [PubMed] [Google Scholar]
- Suzuki H. Recent advances in abzyme studies. J Biochem. 1994 Apr;115(4):623–628. doi: 10.1093/oxfordjournals.jbchem.a124385. [DOI] [PubMed] [Google Scholar]
- TROWBRIDGE C. G., KREHBIEL A., LASKOWSKI M., Jr SUBSTRATE ACTIVATION OF TRYPSIN. Biochemistry. 1963 Jul-Aug;2:843–850. doi: 10.1021/bi00904a037. [DOI] [PubMed] [Google Scholar]
- Tawfik D. S., Green B. S., Chap R., Sela M., Eshhar Z. catELISA: a facile general route to catalytic antibodies. Proc Natl Acad Sci U S A. 1993 Jan 15;90(2):373–377. doi: 10.1073/pnas.90.2.373. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Van Regenmortel M. H. Molecular recognition in the post-reductionist era. J Mol Recognit. 1999 Jan-Feb;12(1):1–2. doi: 10.1002/(SICI)1099-1352(199901/02)12:1<1::AID-JMR449>3.0.CO;2-P. [DOI] [PubMed] [Google Scholar]
- Wharton C. W., Cornish-Bowden A., Brocklehurst K., Crook E. M. Kinetics of the hydrolysis of N-benzoyl-L-serine methyl ester catalysed by bromelain and by papain. Analysis of modifier mechanisms by lattice nomography, computational methods of parameter evaluation for substrate-activated catalyses and consequences of postulated non-productive binding in bromelain- and papain-catalysed hydrolyses. Biochem J. 1974 Aug;141(2):365–381. doi: 10.1042/bj1410365. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wharton C. W., Crook E. M., Brocklehurst K. The preparation and some properties of bromelain covalently attached to O-(carboxymethyl)-cellulose. Eur J Biochem. 1968 Dec 5;6(4):565–571. doi: 10.1111/j.1432-1033.1968.tb00482.x. [DOI] [PubMed] [Google Scholar]