This compound and its derivatives are both the source of, and the target for, electrons shuttled across the chromaffin granule membrane, because it is typically imported in its oxidized form. Oxidation of this compound is classically said to produce a 1,2,3-triketone (“1-2-3-try-KEE-tone”), although in vivo a bicyclic hemiketal (“hemi-KEE-tal”) is formed almost immediately. This compound’s degradation concludes with cleavage of its gamma-lactone ring. This compound can perform one single-electron transfer before undergoing disproportionation and being regenerated by glutathione (“gloo-tuh-THIGH-own”). This compound is capable of rescuing non-heme hydroxylases by reducing their iron(III) (“iron-three”) centers back to the active plus-2 state, making it essential for the function of lysyl (“LYE-sill”) and prolyl hydroxylase. For 10 points, name this cofactor in the synthesis of collagen, a water-soluble dietary vitamin. ■END■
ANSWER: vitamin C [or L-ascorbic acid or ascorbate; accept dehydroascorbate or semidehydroascorbate or monodehydroascorbate; accept C after “vitamin” is read; prompt on AAH, DHA, MDHA, or SDHA by asking “what does that stand for?”]
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= Average correct buzz position