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130 THE PROTEIN SUBSTANCES.
peptone takes place into aniipeptone and hemipcptone. Of these two
peptones the hemipeptone is further split into amino-acids and other
bodies while the antipeptone is not attacked. By the sufficiently
energetic action of trypsin only one peptone remains to the last—the so-
called antipeptone.
Kuhne and his pupils, who have conducted extensive investiga-
tions on the proteoses and peptones, classify the various proteoses accord-
ing to their different solubilities and precipitation properties. In the
pepsin digestion of fibrin l
they obtained the following proteoses : (a)
Heteroproteose, insoluble in water but soluble in dilute salt solution;
(6) Protoproleose, soluble in salt solution and water. These two pro-
teoses are precipitated by NaCl in neutral solutions, but not completely.
Heteroproteose may, by being in contact with water for a long time
or by drying, be converted into a modification, called (c) Dysproteose,
which is insoluble in dilute salt solutions, (d) Deuteroproteose is a pro-
teose which is soluble in water and dilute salt solution and which is
incompletely precipitated from acid solution by saturating with NaCl,
and is not precipitated from neutral solutions.
The proteoses obtained from different protein bodies do not seem to be
identical, but differ in their behavior to precipitants. Special names have been
given to these various proteoses according to the mother-protein, namely, albu-
moses, globidoses, vitelloses, caseoses, myosinoses, elastoses, etc. These various
proteoses are further distinguished, as proto-, hetero-, and deuterocaseose, for
example. Chittenden 2
has suggested the common name proteoses for the prod-
ucts formed intermediary between the proteins and peptones in the digestion of
animal and vegetable proteins. We have made use of it in this sense in pref-
erence to the word albumose (which is used in the German and by some other
writers), but which will be used in this book as indicating the intermediary
products in the hydrolysis of albumins and not as a general term. Certain
proteoses have also been obtained in a crystalline state (Schrotter) .
Neumeister 3
designates as atmidalbumose that body which is obtained by
the action of superheated steam on fibrin. At the same time he also obtained a
substance called atmidalbumin, which stands between the albuminates and the
proteoses.
Of the soluble proteoses Neumeister designates the protoproteose
and heteroproteose as primary proteoses, while the deuteroproteoses,
which are closely allied to the peptones, he calls secondary proteoses. As
essential differences between the primary and secondary proteoses he
’See Kuhne and Chittenden, Zeitschr. f. Biologie, 20.
* Kuhne ami Chittenden, Zeitschr. f. Biologie, 22 and 26; Neumeister, ibid., 23;
Chittenden and Hartwell, Journ. of Physiol., 11 and 12; Chittenden and Painter,
Studies from the Laboratory, etc., Yale University, 2, New Haven, 1887; (l.ittenden,
ibid., .’5:
Sebelien, Chem. Centralblatt, 1890; Chittenden and Goodwin, Journ. of
Physiol.. 12.
3
Zeitschr. f. Biologie, 26. See also Chittenden and Meara, Journ. of Physiol.,
15, and Salkowski, Zeitschr. f. Biologie, 34 and 37.
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