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After the result’s treatment, we obtained different values of Km and Vmax which we can see in table 8.
In michaelis-menten equation at very high values of substrate concentration the initial rate begins to stabilize when approaching the maximal rate, however the maximal rate is difficult to determinate because even the substrate concentration is equal to ten times Km, initial rate is only 91% of maximal rate. That is the reason for some errors occurred into results.
A better method for determinating the kinetic constants than Michaelis-menten equation is the Lineweaver-Burk method however this method has a disadvantage which is for small values of substrate concentration , small errors in the initial rate can lead to large errors on the inverse of initial rate which lead to larger errors in Km and Vmax.
On the other hand, we have the Eadie.-Hofstee Method that is more robust than the one I mentioned before.
The advantage of this method over the Lineweaver-Burk method is that the initial rate appears on its own instead of as a reciprocal. However, the Eadie-Hofstee plot involves compound variables, i.e. V0/[S], which are more difficult to comprehend than when the independent variables are separate.
The Hanes-Woolf method has a great advantage over others because it does not account for the low values of substrate concentration and so comparing the results in table 8, the value obtained for the maximal rate and michaelis-menten constant through this method will be more accurate.
By using literature, we found a reference value for the Michaelis-Menten constant of 20,95 g/L that was similar with the values obtained experimentally. However it should be taken into account that the enzyme is not the same, and the pH and temperature of reference for this value was 5 and 50 º C, respectively.
Other reason to take into consideration is the fact of the cells of Saccharomyces bayanus are very old so they might lost they’re enzymatic activity and there also the