Question

The following metabolite was detected in the urine of a worker at a chemical plant. Working backwards from the metabolite shown to the parent (original) chemical, fill in the blanks for the biotransformation pathway that resulted in the excreted metabolite, drawing the chemicals and listing the full names of any enzymes and cofactors involved. (2 marks each, 14 marks total) 9. Phase Il metabolite (draw) Enzyme: Cofactor(s) Phase I metabolite (draw) Enzyme Cofactor(s) Original chemical (draw)

Answer 1

The metabolite BROMOBENZENE excreted in the urine of the worker is derived from the following process as follows:

PHASE ii METABOLITE: 4-bromo phenol

ENZYME: glutathione peroxidase (sulfhydryl group)

COFACTOR: glutathione

PHASE i METABOLITE: BROMO BENZENE 3,4 EPOXIDE

ENZYME:   NADPH CYTOCHROME P-450 REDUCTASE

CO-FACTOR ; FAD (Flavin adenine dinucleotide)

ORIGINAL CHEMICAL: 3,4 dihydrobromobenzene

overall biotransformation: