This review from 2018 examines the role of molybdenum in the body and covers key sources, historical context, and clinical and preclinical data. In humans, only 4 enzymes requiring molybdenum have been identified to date: sulfite oxidase, xanthine oxidase, aldehyde oxidase and mitochondrial amidoxime-reducing component (mARC). Sulfite oxidase, an enzyme found in mitochondria, catalyzes oxidation of sulfite to sulfate, the final step in oxidation of sulfur amino acids (cysteine and methionine).
Novotny JA, Peterson CA. Molybdenum. Adv Nutr. 2018 May 1;9(3):272-273. doi: 10.1093/advances/nmx001. PMID: 29767695; PMCID: PMC5952949.