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164 THE PROTEIN SUBSTANCES.
{0.07 and 0.15 per cent in two different fractions). The generally
accepted view that lysine is completely absent in gliadin is still doubtful.
They could not detect lysine in zein by the same method.
Lysine has been synthetically prepared by E. Fischer and Weigert.1
This lysine was racemic, while that prepared from protein is always
optically active and dextrorotatory. The rotation depends upon the
concentration and degree of acidity; for the hydrochloride a rotation of
(«)d = +14° to 17.25° has been found. . On heating with barium hydroxide
it is converted into the racemic modification. According to Ellinger
lysine yields cadaverine (pentamethylenediamine), CsHio(NH~2)2, on
putrefaction, and this base is formed from the lysine in the organism
of those with cystinuria and at the same time CO2 is split off (A. Loewy
and Neuberg).2
Lysine is readily soluble in water but is not crystallizable. The aque-
-ous solution is precipitated by phosphotungstic acid, but not by silver
nitrate and baryta-water (differing from arginine and histidine). It
gives two hydrochlorides with hydrochloric acid, and with platinum
chloride a chloroplatinate which is precipitable by alcohol and has the
composition CoHn^C^.H^PtCle-r^HsOH. It gives two silver salts
with AgNOs; one has the formula AgN03+CeHi4N202 and the other
AgN03+CGHi4N2 02.HN03. With benzoyl chloride and alkali, lysine
forms an acid, lysuric acid, C6Hi2(C7H50)2N202 (Drechsel), which
is homologous with ornithuric acid, and whose difficultly soluble acid
barium salt may be used in the separation of lysine.3
The rather
insoluble picrate, which is precipitated from a not too dilute solution
of the hydrochloride by sodium picrate, may also be used in the detec-
tion of lysine.
Kutscher and Lohmann 4
have found a lysine having somewhat different
properties in the final products of pancreas autolysis.
In the preparation of the so-called hexone bases we can first precipitate
all the bases by phosphotungstic acid, when the monamino-acids remain in
solution. The precipitate is then decomposed in boiling water by barium
hydroxide and the bases obtained as silver compounds from this filtrate.
In regard to further details and the methods of separating the various
and Kutscher, ibid., 31; Kutscher, ibid., 29; Schulze, ibid., 28; Winterstein, cited in
Schulze and Winterstein, Ergebnisse der Physiologic, I, Abt. 1, 1902; Kossel and
Dakin, Zeitschr. f. physiol. Chem., 40; Osborne and Leavenworth, Journ. of biol.
Chem., 14
1
Ber. «l. d. chem Gesellsch., 35.
2
See footnote 3, p. 163.
3
Drechsel, Ber. d. d. chem. Gesellsch., 28; see also C. Willdenow, Zeitschr. f. physiol.
Chem.. 2.V
* Zeitschr. f. physiol. Chem., 41.
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