| 释义 |
allosteric, a. Biochem.|æləʊˈstɛrɪk, -ˈstɪərɪk|
[f. allo- + steric a.]
Pertaining to or involving a change in an enzyme's affinity for a substrate as a result of a change in its conformation by the attachment of a molecule not analogous to the substrate molecule at a site other than the substrate binding site; pertaining to any change in conformation caused by the attachment of a ligand.
1962Monod & Jacob in Cold Spring Harbor Symp. Quantitative Biol. XXVI. 391/1 In 1954, Novick and Szilard discovered that the synthesis of a tryptophan precursor..was inhibited by tryptophan... The work of Umbarger..demonstrated that, in many pathways, an early enzyme is so constructed as to be strongly and specifically inhibited by the..endproduct... The most remarkable feature of the Novick-Szilard-Umbarger effect is that the inhibitor is not a steric analogue of the substrate. We propose therefore to designate this mechanism as ‘allosteric inhibition’. 1962H. A. Krebs in A. Pirie Lens Metabolism Rel. Cataract 351 In competition inhibitions, substrate and inhibitor react with the same site of the enzyme molecule. Allosteric inhibitions involve different sites. 1970R. W. McGilvery Biochem. xiii. 247 There evidently is a second site on the protein, allosteric rather than catalytic, at which ATP also binds and causes a modification of the protein structure to an inactive form. 1971J. Z. Young Introd. Study Man iii. 64 Such ‘allosteric’ proteins may..be the basis of regulation of gene action. 1982J. L. York in T. M. Devlin Textbk. Biochem. iv. 171 The modulating ligands that bind at the allosteric site are known as the allosteric effectors or modulators.
Hence alloˈsterically adv.; alloˈsterism = allostery.
1967Proc. Nat. Acad. Sci. LVIII. 1955 If the ion affinity center of an ionophore could be altered allosterically by energy-linked reversible configurational changes, it would acquire the requisites for promoting active transport. 1976Ann. Rev. Microbiol. XXX. 288 Both the S. faecalis and L. casei malic enzymes were shown to be allosterically regulated proteins. 1977Jrnl. Protozool. XXIV. 3/2 With the concepts ‘cooperativity’ and ‘allosterism’ plainly before us, let us begin to look at some cell patterns. Ibid. 6/2 It is allosterically controlled by binding at other sites of the dimer. 1982J. L. York in T. M. Devlin Textbk. Biochem. iv. 175 The relationship between allosterism and cooperativity has been confused in many recent texts. |