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).
References:
Novotny JA, Peterson CA. Molybdenum. Adv Nutr. 2018 May 1;9(3):272-273. doi: 10.1093/advances/nmx001. PMID: 29767695; PMCID: PMC5952949.