Lanthionine

Chembox new
Name = Lanthionine
ImageFile = Lanthionine.png Section1 = Chembox Identifiers
PubChem = 675804
CASNo = 922-55-4
Section2 = Chembox Properties
Formula = C₆H₁₂N₂O₄S
MolarMass = 208.2318 g/mol
MeltingPt = 280-283 °C

Lanthionine is a nonproteinogenic amino acid with the chemical formula (HOOC-CH(NH₂)-CH₂-S-CH₂-CH(NH₂)-COOH). As the monosulfide analog of cystine, lanthionine is composed of two alanine residues that are crosslinked on their β-carbon atoms by a thioether linkage.

Background

In 1941, lanthionine was first isolated from the treatment of wool with sodium carbonate [Horn, M. J.; Jones, D. B.; Ringel, S. J. (1941) Isolation of a New Sulfur-Containing Amino Acid (Lanthionine) from Sodium Carbonate-Treated Wool. "Journal of Biological Chemistry", "138", 141-149.] and was first synthesized from cysteine and β-chloroalanine. [Brown, G. B.; du Vigneaud, V. (1941) The Stereoisomeric Forms of Lanthionine. "Journal of Biological Chemistry", "140", 767-771.] Lanthionines are found widely in nature and have been isolated from human hair, lactalbumin, and feathers. Lanthionines have also been found in bacterial cell walls and are the components of a group of gene encoded peptide antibiotics called lantibiotics, which includes nisin (a food preservative), subtilin, epidermin (an anti staphylococcus and streptococcus agent), and ancovenin (an enzyme inhibitor). [Paul, M.; van der Donk, W. A. (2005) Chemical and Enzymatic Synthesis of Lanthionines. "Mini-Reviews in Organic Chemistry", "2", 23-37.] Shao, H.; Wang, S. H. H.; Lee, C.-W.; Ösapay, G.; Goodman, M. (1995) A Facile Synthesis of Orthogonally Protected Stereoisomeric Lanthionines by Regioselective Ring Opening of Serine β-Lactone Derivatives. "Journal of Organic Chemistry", "60", 2956-2957.]

Preparation

A variety of syntheses of lanthionine have been published including sulfur extrusion from cystine, [Harpp, D. N.; Gleason, J. G. (1971) Preparation and Mass Spectral Properties of Cystine and Lanthionine Derivatives. Novel Synthesis of L-Lanthionine by Selective Desulfurization. "Journal of Organic Chemistry", "36", 73-80.] ring opening of serine β-lactone, and hetero-conjugate addition of cysteine to dehydroalanine. [Probert, J. M.; Rennex, D.; Bradley, M. (1996) Lanthionines for Solid Phase Synthesis. "Tetrahedron Letters", "37", 1101-1104.] The sulfur extrusion method is, however, the only pathway for lanthionine that has been employed in the total synthesis of a lantibiotic.

References