Keggin-type polyoxometalate embedded polyvinylidene fluoride for thin film microextraction of organophosphorus pesticides
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ABSTRACT:
SUBMITTER: Darvishnejad F
PROVIDER: S-EPMC10534218 | biostudies-literature | 2023 Sep
REPOSITORIES: biostudies-literature
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Project description:Exposure to organophosphorus pesticides (OP) can have chronic adverse effects that are independent of inhibition of acetylcholinesterase, the classic target for acute OP toxicity. In pure proteins, the organophosphorus pesticide chlorpyrifos oxon induces a crosslink between lysine and glutamate (or aspartate) with loss of water. Tubulin is particularly sensitive to OP-induced crosslinking. Our goal was to explore OP-induced crosslinking in a complex protein sample, MAP-rich tubulin from Sus scrofa, and to test 8 OP for their capacity to catalyze isopeptide crosslinking. We treated 100 µg of MAP-rich tubulin with 100 µM chlorpyrifos, chlorpyrifos oxon, methamidophos, paraoxon, diazinon, diazoxon, monocrotophos, or dichlorvos. Each sample was separated on SDS PAGE and stained with Coomassie blue. Five gel slices (at about 30, 50, 150, and 300 kDa, and the top of the separating gel) were removed from the lanes for each of the eight OP samples and from untreated control lanes. These gel slices were subjected to in-gel trypsin digestion. MSMS fragmentation spectra of the tryptic peptides were examined for isopeptide crosslinks. Sixteen spectra yielded convincing evidence for isopeptide crosslinked peptides. Ten were from the chlorpyrifos oxon reaction, 1 from dichlorvos, 1 from paraoxon, 1 from diazinon, and 3 from diazoxon. It was concluded that catalysis of protein crosslinking is a general property of organophosphorus pesticides and pesticide metabolites.
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