title: Inhibition of camel lens zeta-crystallin/NADPH: quinone oxidoreductase activity by chlorophenols.
abstract: Chlorophenols comprise a major class of environmental contaminants. They are extensively used as insecticides, fungicides, mold inhibitors, antiseptics and disinfectants. We found some of these compounds to be strong inhibitors of zeta-crystallin. This oxidoreductase enzyme was isolated from camel lens and its enzymatic activity was inhibited by the chlorophenols tested in a time-independent but concentration-dependent manner. 2,4,5-Trichlorophenol was the most potent inhibitor (IC50 = 3 microM; Ki = 3.2 microM) whereas 4-chlorophenol was the least potent (IC50 = 4.1 mM). There appeared to be a relationship between the degree of chlorination of the phenols and inhibition of zeta-crystallin activity. The position of the chlorine substituent on the phenol may also influence the potency of these compounds.
authors.affiliation: Department of Science, King Khalid Military Academy, Riyadh, Kingdom of Saudi Arabia.
authors.forename: R A
authors.initials: RA
authors.lastname: Shehu
authors.forename: A A
authors.initials: AA
authors.lastname: al-Hamidi
authors.forename: N
authors.initials: N
authors.lastname: Rabbani
authors.forename: A S
authors.initials: AS
authors.lastname: Duhaiman
mesh_terms: D000818:Animals; D002162:Camelus; D002733:Chlorophenols / Q000494:pharmacology*; D003459:Crystallins / Q000037:antagonists & inhibitors* / Q000302:isolation & purification / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007700:Kinetics; D007908:Lens, Crystalline / Q000201:enzymology*; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000037:antagonists & inhibitors*; D011809:Quinones / Q000378:metabolism; D013329:Structure-Activity Relationship; D038226:zeta-Crystallins
chemical_list: D002733:Chlorophenols; D003459:Crystallins; D004791:Enzyme Inhibitors; D011809:Quinones; D038226:zeta-Crystallins; D016660:NAD(P)H Dehydrogenase (Quinone)