TY - JOUR
T1 - Verification of organophosphorus pesticide poisoning
T2 - Detection of phosphorylated tyrosines and a cysteine-proline disulfide-adduct from human serum albumin after intoxication with dimethoate/omethoate
AU - Kranawetvogl, Andreas
AU - Siegert, Markus
AU - Eyer, Florian
AU - Thiermann, Horst
AU - John, Harald
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/12/15
Y1 - 2018/12/15
N2 - A method is described allowing forensic analysis of plasma samples to prove human poisoning with the organophosphorus pesticides omethoate (OM) and dimethoate (DIM). Upon incubation of human serum albumin (HSA) with both pesticides tyrosine residues were phosphorylated. In addition, a novel disulfide-adduct between the identical thiol-containing leaving group of OM and DIM (2-mercapto-N-methylacetamide, MNMA) and the only free cysteine residue in HSA (Cys34) was formed. Following pronase-catalyzed proteolysis either O,O-dimethyl phosphotyrosine (Tyr-dmp) or O,O-dimethyl thiophosphotyrosine (Tyr-dmsp) as well as the cysteine-proline dipeptide disulfide-adduct (MNMA-CysPro) were produced. All biomarkers were simultaneously detected using modern microbore liquid chromatography-electrospray ionization high-resolution tandem-mass spectrometry (μLC-ESI MS/HR MS). Corresponding limits of identification (LOI) for tyrosine-adducts (LOIOM: 30 μM, LOIDIM: 120 μM) and disulfide-adducts (LOIOM: 1.2 μM, LOIDIM: 30 μM) demonstrated that MNMA-CysPro allowed a considerably more sensitive detection. Finally, this novel method was applied to a plasma sample of an 87-year-old man, who had unintentionally ingested the pesticide Roxion® containing DIM as active ingredient. Unambiguous proof of poisoning demonstrated suitability of the novel biomarkers for sensitive verification analysis.
AB - A method is described allowing forensic analysis of plasma samples to prove human poisoning with the organophosphorus pesticides omethoate (OM) and dimethoate (DIM). Upon incubation of human serum albumin (HSA) with both pesticides tyrosine residues were phosphorylated. In addition, a novel disulfide-adduct between the identical thiol-containing leaving group of OM and DIM (2-mercapto-N-methylacetamide, MNMA) and the only free cysteine residue in HSA (Cys34) was formed. Following pronase-catalyzed proteolysis either O,O-dimethyl phosphotyrosine (Tyr-dmp) or O,O-dimethyl thiophosphotyrosine (Tyr-dmsp) as well as the cysteine-proline dipeptide disulfide-adduct (MNMA-CysPro) were produced. All biomarkers were simultaneously detected using modern microbore liquid chromatography-electrospray ionization high-resolution tandem-mass spectrometry (μLC-ESI MS/HR MS). Corresponding limits of identification (LOI) for tyrosine-adducts (LOIOM: 30 μM, LOIDIM: 120 μM) and disulfide-adducts (LOIOM: 1.2 μM, LOIDIM: 30 μM) demonstrated that MNMA-CysPro allowed a considerably more sensitive detection. Finally, this novel method was applied to a plasma sample of an 87-year-old man, who had unintentionally ingested the pesticide Roxion® containing DIM as active ingredient. Unambiguous proof of poisoning demonstrated suitability of the novel biomarkers for sensitive verification analysis.
KW - Albumin
KW - Disulfide-adduct
KW - High-resolution mass spectrometry
KW - Organophosphorus pesticide
KW - Verification
UR - http://www.scopus.com/inward/record.url?scp=85053195685&partnerID=8YFLogxK
U2 - 10.1016/j.toxlet.2018.08.013
DO - 10.1016/j.toxlet.2018.08.013
M3 - Article
C2 - 30165092
AN - SCOPUS:85053195685
SN - 0378-4274
VL - 299
SP - 11
EP - 20
JO - Toxicology Letters
JF - Toxicology Letters
ER -