Naslov
Quantification of butyrylcholinesterase active sites in purified preparations using organophosphorus compounds

Autori
Kovarik, Zrinka ; Latas, Tatjana ; Simeon-Rudolf, Vera

Izvornik
Periodicum biologorum (0031-5362) 104 (2002), 4; 481-485

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
DEPQ; haloxon; active site titration; inhibition; cholinesterase

Sažetak
Background and purpose: The inhibition of butyrylcholinesterase (BChE ; EC 3.1.1.8) by covalently binding inhibitors such as organophosphorus compounds makes it possible to determine the quantity of the enzyme active sites in samples. This approach is applicable only if the phosphorylated enzyme conjugate is stable. The kinetics of interaction of horse serum BChE with DEPQ (7-(O, O-diethylphosphinyloxy)-1-methylquinolinium methyl sulphate) and haloxon (O, O-di-(2-chloroethyl)-O-(3-chloro-4-methylcoumarin-7-yl) phosphate) was studied in order to evaluate whether these compounds were suitable for quantification of active sites in a commercial preparation of horse serum BChE. Materials and methods: The BChE preparation was inhibited by haloxon and DEPQ, and the inhibition rate constants were calculated. The rate constant of spontaneous reactivation of BChE phosphorylated by haloxon was determined. Stoichiometric subnanomolar concentrations of the inhibitor and enzyme were used for the quantification of the active sites. The enzyme activity was measured spectrophotometricaly using acetylthiocholine as the substrate. Results and conclusions

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA