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PROTEOSES AND PEPTONES. 135
tyrosine and indoi but abundant leucine and glycocoll, and about 39
per cent of the total nitrogen in a basic form. The protoproteose,
according to Pick, on the contrary yields considerable tyrosine and indol,
only little leucine but no glycocoll, and contains only about 25 per cent
basic nitrogen. Friedmann, Hart, and Levene have obtained very
similar results in regard to the quantity of basic nitrogen in the two-pro-
teoses, although Leyene as well as Adler l
did not find the same results
as Pick in regard to the amounts of monamino-acids in the two proteoses.
The work of Levene, v. Slyke and Birchard 2
show, in many important
points, a decided contradiction to the statements of Pick and these
divergent results may possibly be explained by the fact that they were
not working with pure substances, but rather with mixtures.
According to Pick the heteroproteose is also more resistant toward
tryptic digestion than the protoproteose, a behavior which coincides
with Kuhne’s view of a resistant atomic complex, an anti group, in the
protein bodies. Kuhne and Chittenden 3
regularly obtained on the
tryptic digestion of heteroproteose a separation of so-called antialbumid,
a body which is attacked with great difficulty in tryptic digestion, but
which separates as a jelly-like mass and which is richer in carbon (57.5-
58.09 per cent), but poorer in nitrogen (12.61-13.94 per cent), than the
original protein. The occurrence of such resistant complexes in diges-
tion has also been repeatedly observed.
This antialbumid later attracted increased interest, because as
first found by Danilewsky and later other investigators have shown,
that solutions of rennin, gastric juice, pancreatic juice, and papain cause
a similar coagulum in not too dilute proteose solutions. These coagula,
called plasteines (coagulum by rennin) by Sawjalow, and coaguloses
(coagulum by papain) by Kurajeff,4
are similar in many respects to
antialbumid, having a higher content of carbon (57-60 per cent) and
nitrogen (13-14.6 per cent). In other cases the quantity of carbon as
well as nitrogen is lower (Lawrow).
We cannot for the present make any positive statement as to the
importance and mode of formation of the coaguloses or plasteins. It
1
Hart, Zeitschr. f. physiol. Chem., 33; Pick, ibid., 28; Friedmann, ibid., 29; Levene,
Joum. of Biol. Chem., 1; R. Adler, Die Heteroalbumose und Protalbumose des Fibrins
Dissert. Leipzig, 1907.
2
Joum. of Biol. Chem., 8 and 10.
3
Zeitschr. f. Biol., 19 and 20.
4
The works of Danilewsky and Okunew are cited and reviewed in the following
Sa\Vjalow, Pfliiger’s Arch., 85, and Centralbl. f. Physiol., 16; and Zeitschr. f. physiol.
Chem., 54; Lawrow and Salaskin, Zeitschr. f. physiol. Chem., 36; Lawrow, ibid., 51,
53, 56 and 60; Kurajeff, Hofmeister’s Beitrage, 1 and 2: see also Sacharow, Biochem.
Centralbl., 1, 233; Levene and v. Slyke, Biochem. Zeitschr., 13.
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