pLaidler (1955) showed that consideration of the effect of pH on enzymic mechanisms that obey steady-state kinetics leads to the inclusion in the equations of a ‘perturbation term’ that can introduce curvature into the Lineweaver–Burk plots. He also stated conditions in which this term vanishes. This term can lead to apparent activation by substrate. Further, several cases are shown in which simplification, but not disappearance, of the perturbation term can lead to linearity of Lineweaver–Burk plots. These cases arise when the ionization of groups at the active site either is unaffected or is completely prevented when the enzyme–substrate complex is formed. It is also shown that iV/isub(app.)/sub can vary with pH without a concomitant change in iK/isubim/i(app.)/sub in certain cases that obey steady-state kinetics without implying that iKsubm/sub/i=iKsubs/sub/i. When the perturbation term is significant, Dixon9s (1953) rules for the calculation of piK/i values will not always apply./p
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机译：> Laidler（1955）表明，考虑pH值对服从稳态动力学的酶机制的影响，导致方程中包含“扰动项”，该扰动项可将曲率引入Lineweaver-Burk图。他还指出了该术语消失的条件。该术语可以导致底物的明显活化。此外，显示了几种情况，其中扰动项的简化而不是消失可以导致Lineweaver-Burk图的线性。当形成酶-底物复合物时，当活性位点上的基团电离不受影响或完全被阻止时，就会出现这些情况。还显示 V （app。）可以随pH的变化而变化，而 K m （app。）在某些情况下服从稳态动力学，并不暗示 K m = K s 。当扰动项很重要时，Dixon9s（1953）的计算p K 值的规则将并不总是适用。
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