Structural Basis of Binding and Rationale for the Potent Urease Inhibitory Activity of Biscoumarins
Table 1
Enzymes
Compounds
(M) ± SEM
(mM)
(mM)
(mol/min)−1
Type of inhibition
Urease (JB)
1
19.3 ± 0.1
2.5
5.6
105
109
Competitive
2
71.0 ± 0.3
2.5
7.7
105
106
Competitive
3
59.4 ± 0.1
2.5
8.3
105
108
Competitive
4
65.9 ± 0.0
2.5
9.1
105
105
Competitive
5
53.3 ± 0.4
2.5
7.8
105
103
Competitive
6
75.0 ± 0.1
2.5
9.5
105
106
Competitive
7
15.0 ± 0.1
2.5
7.6
105
102
Competitive
8
21.5 ± 0.0
2.5
7.5
105
104
Competitive
9
62.9 ± 0.5
2.5
11.6
105
108
Competitive
10
68.0 ± 0.1
2.5
10.6
105
105
Competitive
Urease (BP)
1
15.5 ± 0.2
5.1
11.3
160
159.3
Competitive
2
51.3 ± 0.4
5.1
5.2
160
98.0
Noncompetitive
3
53.0 ± 0.01
5.1
4.0
160
115.3
Uncompetitive
4
48.3 ± 0.01
5.1
3.8
160
101.0
Uncompetitive
5
68.1 ± 0.3
5.1
3.9
160
93.7
Uncompetitive
6
27.5 ± 0.0
5.1
13.0
160
159.2
Competitive
7
13.3 ± 0.2
5.1
9.9
160
162.5
Competitive
8
19.0 ± 0.1
5.1
7.7
160
161.7
Competitive
9
59.5 ± 0.2
5.1
3.2
160
97.2
Uncompetitive
10
63.6 ± 0.2
5.1
10.3
160
115.5
Competitive
(dissociation constant or inhibition constant) was determined from nonlinear regression analysis by Dixon plot and secondary Lineweaver-Burk plot at various concentrations of 1–10, (Michaelis-Menten constant) is equal to the reciprocal of -axis intersection, (maximal velocity) is equal to the reciprocal of -axis intersection of each line for each concentration of 1–10 in the Lineweaver-Burk plot. The is equal to the reciprocal of -axis intersection of each line for each concentration of 1–10 in Dixon plot (Each point in Lineweaver-Burk and represents the mean of three determinations). Urease (BP) (Bacillus pasteurii ureases) and urease (JB) (Jack bean urease).
