Linearisation of the HMMequation

Because the hyperbola of the HMM equation approaches Vm^x only very slowly, it is quite difficult to determine Vm^x accurately from such a graph. Nowadays non-linear curve fitting on a computer can be used to estimate Km and Vm^x from v versus [S] data, but the more traditional way is a linear transform of the data. The most common transform is that attributed to Lineweaver & Burk. If 1/v is plotted vs 1/[S] instead of v vs [S], the data points should form a straight line, intersecting the y-axis at 1/Vm^x and the x-axis at -1/Kd (see fig. 6.3).

The HMM-equation can also be expressed in LlNEWEAVER-BuRK-coordinates:

Note that any transformation of data results in a change of their error distribution (see fig. 6.4). Thus calculating Km and Vm^x by linear regression

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