Biofactors. 2009 Jan-Feb;35(1):36-46. doi: 10.1002/biof.8.


Biotin is a water-soluble vitamin and serves as a coenzyme for five carboxylases in humans. Biotin is also covalently attached to distinct lysine residues in histones, affecting chromatin structure and mediating gene regulation. This review describes mammalian biotin metabolism, biotin analysis, markers of biotin status, and biological functions of biotin. Proteins such as holocarboxylase synthetase, biotinidase, and the biotin transporters SMVT and MCT1 play crucial roles in biotin homeostasis, and these roles are reviewed here. Possible effects of inadequate biotin intake, drug interactions, and inborn errors of metabolism are discussed, including putative effects on birth defects.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Animals
  • Biotin / metabolism*
  • Biotinidase / metabolism
  • Carbon-Nitrogen Ligases / metabolism
  • Humans
  • Metabolism, Inborn Errors / metabolism
  • Models, Biological
  • Symporters / metabolism


  • Symporters
  • biotin transporter
  • Biotin
  • Biotinidase
  • Carbon-Nitrogen Ligases
  • holocarboxylase synthetases