Inhibition kinetics of chlorobenzaldehyde thiosemicarbazones on mushroom tyrosinase.
2-Chlorobenzaldehyde thiosemicarbazone (2-Cl-BT) and 4-chlorobenzaldehyde thiosemicarbazone (4-Cl-BT) were synthesized, and their inhibitory kinetics on the activity of mushroom tyrosinase were investigated. Results showed that these compounds exhibited significant inhibitory potency on both monophenolase activity and diphenolase activity of tyrosinase. For the monophenolase activity, both compounds could decrease the steady-state activity of the enzyme sharply, without any influence on the lag period. The IC50 values of them were estimated to be 15.4 μM and 6.7 μM, respectively. For the diphenolase activity, both compounds belonged to reversible inhibitors, but their mechanisms were different: 2-Cl-BT was a noncompetitive type inhibitor, while 4-Cl-BT was a mixed-type inhibitor. Their inhibition constants were determined and compared.
Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China.
Zhi-Cong
ZC
Li
Liang-Hua
LH
Chen
Xiao-Jie
XJ
Yu
Yong-Hua
YH
Hu
Kang-Kang
KK
Song
Xing-Wang
XW
Zhou
Qing-Xi
QX
Chen
D000363:Agaricales / Q000737:chemistry / Q000201:enzymology*; D001547:Benzaldehydes / Q000737:chemistry*; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry*; D005656:Fungal Proteins / Q000037:antagonists & inhibitors* / Q000737:chemistry; D007700:Kinetics; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000737:chemistry; D013882:Thiosemicarbazones / Q000737:chemistry*
D001547:Benzaldehydes; D004791:Enzyme Inhibitors; D005656:Fungal Proteins; D013882:Thiosemicarbazones; D014442:Monophenol Monooxygenase; C032175:benzaldehyde