Full resolution (JPEG) - On this page / på denna sida - II. The Protein Substances - I. Simple Proteins - C. Cleavage Products of Simple Proteins - 3. The Amino-acids
<< prev. page << föreg. sida << >> nästa sida >> next page >>
Below is the raw OCR text
from the above scanned image.
Do you see an error? Proofread the page now!
Här nedan syns maskintolkade texten från faksimilbilden ovan.
Ser du något fel? Korrekturläs sidan nu!
This page has never been proofread. / Denna sida har aldrig korrekturlästs.
ORNITHINE AND LYSINE. 163
CH2 .(NH2)
((’IT ^
(/-Ornithine (a-8-diaminovaleric acid), CsHtsNjOa’ /...V.,. kl
is not a primary
Crl(.\ rl^)
COOH
cleavage product of proteins, but is formed from arginine on boiling with baryta-
water. Jaffe, 1
who first discovered this body, obtained it as a cleavage product
from ornithinic acid, which is found in the urine of hens fed with benzoic acid.
The ornithine which E. Fischer and later Sorensen, 2
have prepared syn-
thetically yields, as shown by Ellinger, putrescine (tetramethylenediamine),
(\H,iX1Ij)j, on putrefaction. A. Loewy and Neuberg 3
have shown that
ornithine is split into putrescine and CO> in the organism of cystinuria patients.
Ornithine is a non-crystalline substance which dissolves in water, giving an
alkaline reaction, and yields several crystalline salts. It is precipitated by
phosphotungstic acid and several metallic salts, but not by silver nitrate and
baryta-water (differing from arginine). Ornithine hydrochloride is dextrorotatory;
the synthetically prepared one is inactive. On shaking ornithine with benzoyl
chloride and caustic soda it is converted into dibenzoylornithine (ornithuric
acid). On splitting artificially prepared racemic ornithuric acid Sorensen has
shown that the naturally occurring ornithuric acid is identical with the dextro-
rotatory a-5-dibenzoyldiaminovaleric acid. Salts and derivatives of ornithine
have been described by Kossel and his collaborators 4
and they have given a
method for its isolation from mixtures.
Diaminoacetic acid, C
,
jH6 X..Oj=CH(XHj)oCOOH was obtained by Drechsel 5
as a cleavage product of casein by boiling with tin and hydrochloric acid. It
crystallizes in prisms and gives a monobenzoyl compound which is not very soluble
in cold water and is almost insoluble in alcohol, and can be usi’d in the isolation
of the acid.
CH2 (NH2)
d-Lysine (a-c-diaminocaproicacid), C6Hi4N20o= ; ltJ ^L \, was first
C rl(J\ri2/
COOH
obtained by Drechsel as a cleavage product of casein. Later he and
his pupils, as well as Kossel and others, found it among the cleavage
products of various proteins. It has not been detected in some vegetable
proteins such as the prolamines (page 1C6). E. Schulze found lysine
in germinating plants of the Lupinus luteus, and Winterstein found
it in ripe cheese. It has been obtained in largest amounts (28.8 per cent)
by Kossel and Dakin from the protamine a-cyprinine. From a gliadin
which was not contaminated and which they considered as a unit substance
although obtained from different fractions having different solubilities
in alcohol, Osborne and Leavenworth 6
found a small amount of lysine
1
Ber. d. d. chem. Gesellsch., 10 and 11.
2
Fischer, Ber. d. d. chem. Gesellsch, 34; Sorensen, Zeitschr. f. physiol. Chem., 44.
3
Ellinger, Zeitschr. f. physiol. Chem., 29; Loewy and Neuberg, ibid., 43.
4
Kossel and Weiss, Zeitschr. f. physiol. Chem., 68.
5
Ber. d. k. sachs. Gesellsch. d. Wiss., 44
6
Drechsel, Arch. f. (Anat. u.) Physiol., 1891, and Ber. d. d. chem. Gesellsch., 25;
Siegfried, Arch. f. (Anat. u.) Physiol., 1891, and Ber. d. d. chem. Gesellsch., 24; Hedin,
Zeitschr. f. physiol. Chem., 21; Kossel, ibid., 25; Kossel and Mathews, ibid., 25; Kossel
<< prev. page << föreg. sida << >> nästa sida >> next page >>
