Molybdenum

The sulfur-containing amino acids, methionine and cysteine, are integral to the production of both collagen, and keratin. Molybdenum is used in the body as part of a complex called molybdenum cofactor. Molybdenum cofactor is required for the enzyme sulfite oxidase, which is used in the metabolism of sulfur-containing amino acids.

References:

  1. Enzyme Therapy - Anthony U. Cichoke, p62