biologia - Studia

M.. DRĂGAN-BULARDA,. R. CARPA, M. MIŞCA, V.-CĂLEAN
4. Determining the enzymatic kinetics
There was determined the Michaelis-Menten constant and V max of reaction.
The data used for calculating K m and V max are indicated in Table 4.
No.
[S]
(mg/
ml)
Calculating K m and V max in the case of Bac.subtilis alpha-amylase
L/[S]
(ml/
mg)
Adsorbance
Concentration
Initial Final Initial Final
V (mg/s)
Table 4.
L/V (s/mg)
1 0.2 5 0.023 0.021 0.214 0.188 0.000433 2307.692
2 0.4 2.5 0.044 0.039 0.398 0.356 0.0007 1428.571
3 0.6 1.66 0.066 0.058 0.599 0.522 0.001283 779.2208
4 0.8 1.25 0.089 0.082 0.802 0.738 0.001067 937.5
5 1 1 0.106 0.092 0.955 0.832 0.00205 487.8049
Fig. 5. The calculation of K m and V max by Lineweaver-Burk method.
The Fig.5 shows the calculation of K m and V max by the Lineweaver-Burk
method. Thus, 1/V max = 210.9, so thati V max =0.0047 mg/s, respectively 0.284
mg/min, while
K m /V max = 428
K m =428 x V max , so that K m = 2.011 mg/ml
128