TY  - JOUR
AU  - Krstić, Danijela Z.
AU  - Čolović, Mirjana B.
AU  - Kralj, Mojca Bavcon
AU  - Franko, Mladen
AU  - Krinulović, Katarina
AU  - Trebše, Polonca
AU  - Vasić, Vesna M.
PY  - 2008
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3499
AB  - Inhibition of bovine erythrocyte acetylcholinesterase (free and immobilized on controlled pore glass) by separate and simultaneous exposure to malathion and malathion transformation products which are generally formed during storage or through natural or photochemical degradation was investigated. Increasing concentrations of malathion, its oxidation product malaoxon, and its isomerisation product isomalathion inhibited free and immobilized AChE in a concentration-dependent manner. K-I, the dissociation constant for the initial reversible enzyme inhibitor-complex, and k(3), the first order rate constant for the conversion of the reversible complex into the irreversibly inhibited enzyme, were determined from the progressive development of inhibition produced by reaction of native AChE with malathion, malaoxon and isomalathion. KI values of 1.3 x 10(-4) M-1, 5.6 x 10(-6) M-1 and 7.2 x 10(-6) M-1 were obtained for malathion, malaoxon and isomalathion, respectively. The IC50 values for free/immobilized AChE, (3.7 +/- 0.2)10(-4) M/(1.6 +/- 0.1)10(-4), (2.4 +/- 0.3)10(-6)/(3.4 +/- 0.1)10(-6) M and (3.2 +/- 0.3)10(-6) M/(2.7 +/- 0.2)10(-6) M, were obtained from the inhibition curves induced by malathion, malaoxon and isomalathion, respectively. However, the products formed due to photoinduced degradation, phosphorodithioic O,O,S-trimethyl ester and O,O-dimethyl thiophosphate, did not noticeably affect enzymatic activity, while diethyl maleate inhibited AChE activity at concentrations GT 10 mM. Inhibition of acetylcholinesterase increased with the time of exposure to malathion and its inhibiting by-products within the interval from 0 to 5 minutes. Through simultaneous exposure of the enzyme to malaoxon and isomalathion, an additive effect was achieved for lower concentrations of the inhibitors (in the presence of malaoxon/isomalathion at concentrations 2 x 10(-7) M/2 x 10(-7) M, 2 x 10(-7) M/3 x 10(-7) M and 2 x 10(-7) M/4.5 x 10(-7)M), while an antagonistic effect was obtained for all higher concentrations of inhibitors. The presence of a non-inhibitory degradation product (phosphorodithioic O,O,S-trimethyl ester) did not affect the inhibition efficiencies of the malathion by-products, malaoxon and isomalathion.
T2  - Journal of Enzyme Inhibition and Medicinal Chemistry
T1  - Inhibition of AChE by malathion and some structurally similar compounds
VL  - 23
IS  - 4
SP  - 562
EP  - 573
DO  - 10.1080/14756360701632031
ER  - 

@article{
author = "Krstić, Danijela Z. and Čolović, Mirjana B. and Kralj, Mojca Bavcon and Franko, Mladen and Krinulović, Katarina and Trebše, Polonca and Vasić, Vesna M.",
year = "2008",
abstract = "Inhibition of bovine erythrocyte acetylcholinesterase (free and immobilized on controlled pore glass) by separate and simultaneous exposure to malathion and malathion transformation products which are generally formed during storage or through natural or photochemical degradation was investigated. Increasing concentrations of malathion, its oxidation product malaoxon, and its isomerisation product isomalathion inhibited free and immobilized AChE in a concentration-dependent manner. K-I, the dissociation constant for the initial reversible enzyme inhibitor-complex, and k(3), the first order rate constant for the conversion of the reversible complex into the irreversibly inhibited enzyme, were determined from the progressive development of inhibition produced by reaction of native AChE with malathion, malaoxon and isomalathion. KI values of 1.3 x 10(-4) M-1, 5.6 x 10(-6) M-1 and 7.2 x 10(-6) M-1 were obtained for malathion, malaoxon and isomalathion, respectively. The IC50 values for free/immobilized AChE, (3.7 +/- 0.2)10(-4) M/(1.6 +/- 0.1)10(-4), (2.4 +/- 0.3)10(-6)/(3.4 +/- 0.1)10(-6) M and (3.2 +/- 0.3)10(-6) M/(2.7 +/- 0.2)10(-6) M, were obtained from the inhibition curves induced by malathion, malaoxon and isomalathion, respectively. However, the products formed due to photoinduced degradation, phosphorodithioic O,O,S-trimethyl ester and O,O-dimethyl thiophosphate, did not noticeably affect enzymatic activity, while diethyl maleate inhibited AChE activity at concentrations GT 10 mM. Inhibition of acetylcholinesterase increased with the time of exposure to malathion and its inhibiting by-products within the interval from 0 to 5 minutes. Through simultaneous exposure of the enzyme to malaoxon and isomalathion, an additive effect was achieved for lower concentrations of the inhibitors (in the presence of malaoxon/isomalathion at concentrations 2 x 10(-7) M/2 x 10(-7) M, 2 x 10(-7) M/3 x 10(-7) M and 2 x 10(-7) M/4.5 x 10(-7)M), while an antagonistic effect was obtained for all higher concentrations of inhibitors. The presence of a non-inhibitory degradation product (phosphorodithioic O,O,S-trimethyl ester) did not affect the inhibition efficiencies of the malathion by-products, malaoxon and isomalathion.",
journal = "Journal of Enzyme Inhibition and Medicinal Chemistry",
title = "Inhibition of AChE by malathion and some structurally similar compounds",
volume = "23",
number = "4",
pages = "562-573",
doi = "10.1080/14756360701632031"
}

Krstić, D. Z., Čolović, M. B., Kralj, M. B., Franko, M., Krinulović, K., Trebše, P.,& Vasić, V. M.. (2008). Inhibition of AChE by malathion and some structurally similar compounds. in Journal of Enzyme Inhibition and Medicinal Chemistry, 23(4), 562-573.
https://doi.org/10.1080/14756360701632031

Krstić DZ, Čolović MB, Kralj MB, Franko M, Krinulović K, Trebše P, Vasić VM. Inhibition of AChE by malathion and some structurally similar compounds. in Journal of Enzyme Inhibition and Medicinal Chemistry. 2008;23(4):562-573.
doi:10.1080/14756360701632031 .

Krstić, Danijela Z., Čolović, Mirjana B., Kralj, Mojca Bavcon, Franko, Mladen, Krinulović, Katarina, Trebše, Polonca, Vasić, Vesna M., "Inhibition of AChE by malathion and some structurally similar compounds" in Journal of Enzyme Inhibition and Medicinal Chemistry, 23, no. 4 (2008):562-573,
https://doi.org/10.1080/14756360701632031 . .

TY  - CONF
AU  - Kralj, Mojca Bavcon
AU  - Trebše, Polonca
AU  - Vasić, Vesna M.
PY  - 2006
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3082
C3  - Toxicology Letters
T1  - Insight in the toxicity of malathion photodegradation product
VL  - 164
IS  - SI
SP  - S249
EP  - S249
DO  - 10.1016/j.toxlet.2006.07.179
ER  - 

@conference{
author = "Kralj, Mojca Bavcon and Trebše, Polonca and Vasić, Vesna M.",
year = "2006",
journal = "Toxicology Letters",
title = "Insight in the toxicity of malathion photodegradation product",
volume = "164",
number = "SI",
pages = "S249-S249",
doi = "10.1016/j.toxlet.2006.07.179"
}

Kralj, M. B., Trebše, P.,& Vasić, V. M.. (2006). Insight in the toxicity of malathion photodegradation product. in Toxicology Letters, 164(SI), S249-S249.
https://doi.org/10.1016/j.toxlet.2006.07.179

Kralj MB, Trebše P, Vasić VM. Insight in the toxicity of malathion photodegradation product. in Toxicology Letters. 2006;164(SI):S249-S249.
doi:10.1016/j.toxlet.2006.07.179 .

Kralj, Mojca Bavcon, Trebše, Polonca, Vasić, Vesna M., "Insight in the toxicity of malathion photodegradation product" in Toxicology Letters, 164, no. SI (2006):S249-S249,
https://doi.org/10.1016/j.toxlet.2006.07.179 . .