Fig. 2.

The free energy profile of the TIM catalysed reaction (dotted line) as well as the buffer catalysed reaction (continuous line) [17]. This free energy profile is constructed from the rates of the relevant reactions; in the case of the second order binding rates for the formation of the enzyme substrate complex, a substrate concentration of 40 μM is assumed [48]. As is also described in the text, each of the steps of the TIM catalysed reaction, visualised in this diagram, namely (1) substrate binding, (2) deprotonation-chemistry (formation of the enediolate), (3) reprotonation-chemistry (formation of product), and (4) release of product, in fact consists of several steps