The first section of this lab report relates the effect of substrate concentration on enzyme activity. I shall briefly discuss and explain what my data shows and means. Graph 3 which is the graph of Michaelis Menten of collected data. The relationship between the rate of an enzyme-catalysed reaction and the substrate concentration can be describes as hyperbolic. The graph and tables 2 show that as the concentration of substrate (PNPP) increases from 0.00 Mmols to 0.20 Mmols of substrate the initial velocity or the rate of reaction shows an increase in too. The relationship can be describes as fist order as the [V] rises almost linearly with the increase in [S].
However after the concentration increase from 0.20- to 3.00 Mmols the initial velocity shows a gradual increase and then gradually levels of or slopes here graph shows 0 order relationship. This supports the prediction I made in the introduction. The graphs indicates that as the concentration of substrate increase the rate of reaction increase this is because of the increase chances of a collision between a substrate and an enzyme. This in turn increases the rate at which ES and P are formed. However after the concentration increase after 0.20 3.00 Mmols the rate stars to level off. The reasoning behind is this is that there are too many substrates than compared to enzymes an all enzymes are described to be fully saturated .At this phase the reaction is at its Maximum velocity and cannot increase in rate unless more enzymes are added therefore enzyme concentration is the limiting factor.
I can tell that the data I collected from the experiment in the lab is accurate and valid as the graph which compares the theatrical data and the collected data show similarities in the trend line the Vmax the km and as well as the points and there is no anomalous data point on either of the 3 graphs. My findings support the findings of many previous investigations and journals as the graphs show a similar relationship as to the findings to previous work. The implications of this investigation can be used widely to determine the Vmax and KM. These values can be used for medical purposes since the enzyme acid phosphatase is manufactured by the body to remove phosphate groups.
The limitation of Michaels Menten plot is that the Km and Vmax cannot be accurately determined. Therefore a Lineweaver burk plot is plotted. The Lineweaver burk plot shows that the KM and Vmax are very similar to the ones from the Michaelis Menten plot.
Finally KM is an approximate measure of the affinity of an enzyme for its substrate.A small value of KM indicates a high affinity of the enzyme for the substrate. From my graphs (1 +2) I can tell that the KM was 0.24 and therefore small. This means that the enzyme acid phosphatase has a high affinity for the synaesthetic substrate PNPP. This means that small concentration of substrate PNPP is enough to run the reaction at half of maximum velocity (1/2 Vmax).
The next section of the investigation concerns the effect of temperature on the rate of reaction. I predicted an increase in temperature will increase the rate of reaction or the initial velocity of the e reaction until the enzyme denatures and the protein sequence becomes damaged an unravels. The actual reason for why the protein sequences unravel is that the protein has too much kinetic energy and the amino acids vibrate and this causes the non covalent forces to be weakened. There is an increase in the rate of reaction as the temperature increases from 278 -323 K the increase is almost linear. However after the temperature 323 K-to 347 K the enzyme denatures and unravels. This is proved by the last point on the graph which doesn't fit the line of best fit. Overall the graphs and data all prove my predictions correct. There is no other anomalous data present.
The third section concerns the effect of pH on the rate of reaction. As we have discovered before the enzyme used was acid phosphatase so the pH at which it works at best - the optimum temperature will be in the acidic pH regions. I can confirm from my graph that the optimum pH of the reaction is in the region 5-5.5 which is indeed acidic. pH of 5.5 gives the highest absorption value, this therefore means that the rate of hydrolysis was at its fastest.
A possible explanation for the change in the experimental design is that the pH may denature the enzyme if the enzyme was added first the active site and 3 dimensional shape of the enzyme could be altered at extremes of pH such as 2 which is quite acidic. The pH does not affect the substrates 3 dimensional structure in the same ways as the enzymes. Therefore to obtain valid results /data the design for this part of the experiment was slightly altered.
pH has a very strong effect on enzyme activity .This is because enzymes work on the basis of mechanisms such as induced fit hypothesis and lock and key . The enzymes have a specific active site due to the complementary 3 di