Title: Lysine
CAS Registry Number: 56-87-1
CAS Name: L-Lysine
Additional Names: Lys; K; (S)-2,6-diaminohexanoic acid; a,e-diaminocaproic acid
Molecular Formula: C6H14N2O2
Molecular Weight: 146.19
Percent Composition: C 49.29%, H 9.65%, N 19.16%, O 21.89%
Literature References: An essential amino acid for human development; probably the most limited in the food chain. Identified in a hydrolysate of casein by Drechsel in 1889. Named "lysatine" from the Greek for "loosing", as it produced urea on treatment with barium hydroxide; changed to "lysine" in 1891. Verification of structure: E. Fischer, F. Weigert, Ber. 35, 3772 (1902). Early chemistry and biochemistry: Amino Acids and Proteins, D. M. Greenberg, Ed. (Charles C. Thomas, Springfield, IL, 1951) 950 pp, passim; J. P. Greenstein, M. Winitz, Chemistry of the Amino Acids vols. 1-3 (John Wiley & Sons, Inc., New York, 1961) pp 2097-2124, passim. Review of supplementation of cereals: C. Feldberg, C. P. Hetzel, Food Technol. 12, 496 (1958); of wheat proteins: S. B. Vaghefi et al., Am. J. Clin. Nutr. 27, 1231-1246 (1974). Review of metabolism in mammals: F. C. Fellows, M. H. R. Lewis, Biochem. J. 136, 329-334 (1973); of metabolic errors: N. A. J. Carson, Clin. Endocrinol. Metab. 3, 71-86 (1974). Brief review of production by fermentation: Nutr. Rev. 43, 88-90 (1985). Review of synthesis: G. Galili, Plant Cell 7, 899-906 (1995).
Properties: Needles from water, hexagonal plates from dil alcohol. Darkens at 210°; dec 224.5°. [a]D20 +14.6° (c = 6.5); [a]D23 +25.9° (c = 2 in 6.0N HCl). pK1 2.18; pK2 8.95; pK3 10.53. Very freely sol in water. Insol in common neutral solvents.
pKa: pK1 2.18; pK2 8.95; pK3 10.53
Optical Rotation: [a]D20 +14.6° (c = 6.5); [a]D23 +25.9° (c = 2 in 6.0N HCl)
Derivative Type: Dihydrochloride
Molecular Formula: C6H14N2O2.2HCl
Molecular Weight: 219.11
Percent Composition: C 32.89%, H 7.36%, N 12.79%, O 14.60%, Cl 32.36%
Properties: Crystals from ethanol + ether, mp 193°. [a]D20 +15.3° (c = 2).
Melting point: mp 193°
Optical Rotation: [a]D20 +15.3° (c = 2)
Derivative Type: Monohydrochloride
CAS Registry Number: 657-27-2
Trademarks: Darvyl; Enisyl (Person & Covey)
Molecular Formula: C6H14N2O2.HCl
Molecular Weight: 182.65
Percent Composition: C 39.45%, H 8.28%, N 15.34%, O 17.52%, Cl 19.41%
Properties: Crystals from dil ethanol. mp 263-264° when anhydrous. [a]D25 +14.6° (c = 2 in 0.6N HCl).
Melting point: mp 263-264° when anhydrous
Optical Rotation: [a]D25 +14.6° (c = 2 in 0.6N HCl)
Derivative Type: Monoorotate
Trademarks: Lysortine (Adrian-Marinier)
Molecular Formula: C11H18N4O6
Molecular Weight: 302.28
Percent Composition: C 43.71%, H 6.00%, N 18.53%, O 31.76%
Literature References: Prepn: GB 922361 (1962 to A.E.C. Soc. Chim. Org. Biol.).
Properties: Crystals, dec 315°.
Use: Enrichment of cereals and feeds. |