CHAP, ii.] KUHNE'S VIEWS. 



Before examining the particular results to which Kiihne arrived 

 we may briefly express their general tendency as follows: every 

 proteid when subjected to hydrolytic decomposition, or to conditions 

 which presumedly bring about decomposition by causing the body 

 in question to combine with the elements of water (such as boiling 

 with dilute sulphuric acid: prolonged heating of dilute hydrochloric 

 acid (0'25 per cent.) at 40 C. : digestion with pepsin and hydro- 

 chloric acid: digestion with trypsin in solution of sodium hydrate or 

 sodium bicarbonate: putrefaction), splits up into bodies which 

 belong to two distinct groups, a hemi-group, and an anti-group. We 

 may conceive of the complex proteid molecule combining with the 

 elements of water and breaking up into two (or more than two) 

 molecules, of which one belongs to the hemi- and the other to the anti- 

 product of decomposition. By the continued action of the hydrolytic 

 agent, the primary cleavage products of each category are further decom- 

 posed, until, under favourable conditions, there result x molecules of 

 antipeptone and of hemipeptone respectively. The bodies of the latter 

 group are distinguished by their greater instability from those of the 

 former group, and, particularly, by the fact that under the influence 

 of trypsin they are capable of being decomposed into substances of 

 comparatively simple constitution and of which the best characterised 

 are leucin, tyrosin, and glutamic acid, whilst the bodies of the 

 anti-group cannot, under the influence of trypsin and an alkali, be 

 split up into bodies less complex than antipeptone. In the first 

 paper 1 in which Kiihne announced the views under discussion he 

 exhibits the relation of certain of the bodies resulting from the 

 ecomposition of a proteid, by the aid of the subjoined schema, which 

 "lews the principal products of the action of hydrolytic agents on 

 >roteids. It will be observed that whilst the ultimate product of the 

 )litting up are peptones, termed respectively anti-peptoue and 

 ^mi-peptone, each of these is related to and derived from a so-called 

 Ibumose. As will be shewn in the sequel, the best characterised of 

 ;he intermediate products occupying a position between the native 

 )roteids and the peptones are the albiimoses, anti- and hemi- 

 bumose respectively bodies which, whilst possessing some of the 

 itions of the true peptones, and particularly exhibiting the so- 



Albumin 



r~ 



Anti -group Hemi-group 



i L 1 



Antialbumid (Hemi-protein) 

 Antialbumat (Parapeptone) 



Antialbumose Hemialbumose 



Antipeptone Hemipeptone 



with his pupil Chittenden. The author has, in many places, quoted descriptions of 

 methods and properties of substances almost verbatim. 



1 Kiihne, 'Weitere Mittheilungen tiber Verdauungsenzyme und die Verdauung der 

 Albumine.' Verhandlungen des naturhist. med. Vereins zu Heidelberg. Bd. I. Heft 4 r 

 S. 236. 



