1. Lineweaver Burk plot (1/V vs 1/S)Hans Lineweaver and Deon Burk took the reciprocal of both the sides of M–M equation. Vo = Vmax[S]/KS + [S]
    1/Vo = Km + [S]/Vmax [S]
    1/Vo = Km/Vmax[S] + [S]/Vmax[S]
    1/Vo = Km/Vmax · 1/[S] +1/VmaxThis is the Lineweaver Burk (LB) equation.LB plot is then a double-reciprocal plot as shown in Figure 6.9.The plot is a straight line unlike M–M plot, which is hyperbolic. The plot is obtained when 1/V is plotted against 1/S.Figure 6.9 A Double-Reciprocal Plot or Lineweaver Burk PlotFigure 6.9 A Double-Reciprocal Plot or Lineweaver Burk PlotAdvantagesAn advantage of LB plot over other plot is that accurate determination of Vmax is possible. One of the major applications of LB is to study enzyme inhibitor.DisadvantageFor high substrate concentration, when we insert it, we get less value and, therefore, a lot of errors will take place while determining the Km.
  2. Eadie–Hofstee plot (V vs V/S) V = Vmax[S]/Km + [S] (M–M equation)Taking reciprocal on both sides, 1/Vo = Km/Vmax[S] + 1/Vmax (LB equation)Multiply by [S] on both sides. [S]/V = Km[S]/Vmax[S] + [S]/VmaxMultiply by Vmax on both sides. [S]Vmax /Vo = KmVmax /Vmax + [S]/Vmax ·Vmax
    [S]/Vo·Vmax = Km + [S]
    [S]Vmax = VoKm + Vo[S]
    Vo[S] =−VoKm + Vmax[S]Divide by [S] Vo =−Km·Vo/[S] + VmaxThis is Eadie–Hofstee’s equation.AdvantagesEH plot is slightly superior to LB plot as it yields accurate Vmax and Km values and magnifies the deviation from linearity which might not be apparent in LB plot as shown in Figure 6.10.Figure 6.10 Eadie–Hofstee plotFigure 6.10 Eadie–Hofstee plotDisadvantageHere, there is still reciprocal of [S].
  3. Augustsson plot [[S]/V vs [S]] or Hanes Wolf plot as shown in Figure 6.11. Vo = Vmax[S]/Km + [S] (M–M equation)Taking reciprocal, 1/Vo = Km /Vmax[S] + 1/Vmax (LB plot)Multiply by[S] [S]/Vo = Km[S]/Vmax[S] + [S]/VmaxThis is Augustsson equation. [S]/Vo = 1/Vmax · [S] +Km/VmaxFigure 6.11 Hanes–Wolf PlotFigure 6.11 Hanes–Wolf Plot

Transformation of M–M equation is given in Table 6.6.

 

Table 6.6 Transformation of M–M Equation

Table 6.6 Transformation of M–M Equation

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