L-2-Thiohistidine


2TH

Synonyms: 2-Mercapto-L-histidine, L-2-thiolhistidine

L-2-Thiohistidine is a 2-thioimidazole analog of L-histidine. The 2-thioimidazole structure has been found as a post-translational modification of copper proteins, such as molluskan hemocyanin and fungal tyrosinase, in the vicinity of the copper ion that is coordinated at the active site of these proteins [1-5].

Stable towards oxygen, L-2-thiohistidine is an efficient antioxidant through its ability to chelate divalent metallic cations, such as Cu2+ and Zn2+ [6,7], and to prevent from singlet oxygen formation [8], a strong oxidizing agent involved in UVA-induced skin damage. This supports the protective effect of L-2-thiohistidine that has been reported in studying the photochemical inactivation of various enzymes [9-11].

References

  1. Primary structure of tyrosinase from Neurospora crassa — LERCH K. — 1982 — J. Biol. Chem., vol. 257, n°11, pp. 6414-6419
  2. Evidence for a cysteine-histidine thioether bridge in functionnal units of molluscan haemocyanins and location of the disulfide bridges in functional units d and g of the βc-haemocyanin of Helix pomatia — GIELENS C. et al. — 1997 — Eur. J. Biochem., vol. 248, pp. 879-888
  3. Chemically modified amino acids in copper proteins that bind or activate dioxygen — HALCROW M.A. — 2001 — Angew. Chem. Int. Ed., vol. 40, n°2, pp. 346-349
  4. Geometric preferences of crosslinked protein-derived cofactors reveal a high propensy for near-sequence pairs — SWAIN M.D. and BENSON D.E. — 2005 — Prot. Struct. Funct. Bioinf., vol. 59, pp. 64-71
  5. Conformational stabilization at the active site of molluskan (Rapana thomasiana) hemocyanin by a cysteine-histidine thioether bridge: A study by mass spectrometry and molecular modeling — GIELENS C. et al. — 2007 — Peptides, vol. 28, pp. 790-797
  6. Inhibition of urocanase by cupric ion — HUG D.H. and ROTH D. K. — 1973 — Biochim. Biophys. Acta, vol. 293, n°2, pp. 497-505
  7. Physico-chemical and metal-binding properties of thiolhistidine — TAKESHIMA S. and SAKURAI H. — 1982 — Inorg. Chim. Acta, vol. 66, pp. 119-124
  8. Some prevalent biomolecules as defenses against singlet oxygen damage — DAHL T.A. et al. — 1988 — Photochem. Photobiol., vol. 47, n°3, pp. 357-362
  9. Oxidation, photosensitized by certain diketones, of enzymes and protection against such oxidation by histidine derivatives — MAKINEN K.K. and MAKINEN P.L. — 1982 — Biosc. Rep., vol. 2, pp. 169-175
  10. Photochemical inactivation of Aeromonas aminopeptidase by 2,3-butanedione — MAKINEN K.K. et al. — 1982 — J. Biol. Chem., vol. 257, n°4, pp. 1765-1772
  11. Photochemical inactivation of lactoperoxidase sensitized by carbonyl compounds — MAKINEN K.K. and MAKINEN P.L. — 1982 — Eur. J. Biochem., vol. 123, pp. 171-178