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DIAMINO-ACIDS. 165
bases we will refer to Steudel in Abderhalden’s Handbuch der biochem-
ischen Arbeitsmethoden, Bd. 2, II, s. 498.
We give below a tabulation of the amounts of the three hexone bases
found in certain protein substances (in weight per cent):
Arginine. Lysine. HLatidine.
Sturine 1
58.2 L2.0 12.9
Cyprinine (a) 6
1 9 is s 0.0
Other protamines » 62.5—87.4 0.0 0.0
Histories 1
14.36—15.52 7.7 —8.3 1.21—2.34
Casein- 4.70—4.84 1.92—5.80 2.53—2.59
Syntonin (from meat) « 5.06 3 26 2.66
Heterosyntonose *
8.53 3.08—7.03 0.37—11
2
Protosyntonose 2
4.55 3.08 3.35
Edestin 3
11.0—14.07 1 .3 117
Proteid from conifera: seeds 3
10 .
9—11 .3 . 25—0 79 . 62—0 78
Gluten casein J
4 4 2.15 1.16
Gluten proteins «
2.75— 3.13 0.0 0.43—1.53
Gelatin ’ and 2
7.62—9.3 2.49—6.0 0.40
Elastin 4
0.3 + 0.027
Of the oxydiamino-acids found on the hydrolysis of proteins we will
mention the following:
Oxydiaminosebacic acid, (?) CwHmNjOb, has been isolated by Wohlgemuth «
from a nucleoprotein of the liver. The free acid was obtained as small white
plates. It is soluble with difficulty in hot water, insoluble in cold water and
in alcohol. It was optically inactive in hydrochloric acid. The beautifully
crystalline phenylcyanate compound had a melting-point of 206°.
Dioxydiaminosuberic acid, C8H,6 X>06 . has been obtained by Skraup 7
on the
hydrolysis of casein with hydrochloric acid. The copper salt crystallizes in
beautiful deep bluish-violet rosettes which are composed of long, irregular, right-
angled plates. It is quite soluble in cold water. The free acid crystallizes in
fern-like formations. Besides this acid Skraup obtained two other acids which
he calls caseanic acid, C9H16N2O7, and caseinic acid, C12H24N0O5. The caseanic
acid crystallizes, melts at 190-191°, is tribasic, and is probably an oxydiamino-
acid. The caseinic acid is dibasic and occurs in two modifications. The one
which melts at 228° is faintly dextrorotatory; the other modification melts
at 245° and is optically inactive. Both crystallize, but the inactive form does
not yield well-defined crystals. Caseinic acid seems also to be an oxydiamino-
acid.
Diaminotrioxydodecanoic acid, Ci2 H26N>05 , is an acid obtained by Fischer and
Abderhalden 8
on the hydrolysis of casein and seems to stand close to Skraup’s
caseinic acid, but differs from it in its optical properties. This acid is faintly
levorotatory: (a) D =about— 9°. It crystallizes in plates, which grow into rosettes
1
Kossel and Kutscher, Zeitschr. f. physiol. Chem., 31.
* Hart, ibid., 33.
3
Schulze and Winterstein, ibid., 33; see also Kossel, Ber. d. d. chem. Gesellsch.,
34, 3236.
4
Kossel and Kutscher, Zeitschr. f. physiol. Chem., 25, and Richards and Gies,
Amer. Journ. of Physiol., 7.
5
Kossel and Dakin, Zeitschr. f. physiol. Chem., 40.
6
Ber. d. d. chem. Gesellsch., 37, and Zeitschr. f. physiol. Chem., 44.
7
Zeitschr. f. physiol. Chem., 42.
8 Zeitschr. f. physiol. Chem.. 42.
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