1903] 



On the Nucleoproteids of the Pancreas, etc. 



387 



•appear to be in unison with the facts known to us (Sehmiedeberg, 

 Levene, W. Jones and G. H. Whipple, T. B. Osborne and L F. 

 Harris).* 



Hammarsten,f to whose researches on the nucleoproteids and their 

 relations to the nucleins we owe much of our knowledge of these 

 bodies, would restrict the term " Nucleins " to the albuminous com- 

 pounds of the nucleinic acids which remain undissolved after prolonged 

 digestion with pepsin and hydrochloric acid. But this limitation 

 appears to us undesirable and unphilosophical, and we think that the 

 term nuclein, which it is convenient to retain, both for historical and 

 descriptive reasons, should be applied to designate all those bodies 

 resulting from the splitting-off of some, but only some, of the albuminous 

 molecules originally forming part of the more complex nucleoproteid 

 mother substance. It is in this sense that we shall in this paper 

 employ the term nuclein, it being understood that every nuclein is to 

 be considered a nucleoproteid, inasmuch as it is a compound of an 

 albuminous body with a nucleinic acid or acids. 



The Researches of Hammarsten on the Nucleoproteids of the Pancreas. 



In his most interesting and suggestive paper published in the year 

 1894, Hammarsten gave an account of two nucleoproteids which he 

 had obtained from the pancreas. 



The first of these bodies he designated proteid : a. He ascertained 

 that this body which, being soluble in water, is present in cold aqueous 

 extracts of the pancreas, is precipitated by acetic acid, and that when 

 boiled its solutions yield a coagulated albuminous substance, the sub- 

 stance remaining in solution being presumably nucleoproteid-/^- 

 Although Hammarsten fully recognised that the first or a-body was 

 the mother substance, and that proteid-/? was only a product of its 

 decomposition, he devoted his attention to the latter, being actuated 

 by the following reasons : — In the first place, his object being at that 

 time to study the non-albuminous products of the pancreatic nucleo- 

 proteid, it appeared to him more simple and wiser to take as the 

 starting-point of the investigation a material containing less albumin. 

 The chief ground, however, for leaving the more interesting nucleo- 

 proteid provisionally uninvestigated was the great difficulty of obtain- 



* O. Sehmiedeberg, ' Archir f. experiment. Path. \\. Pharmak.,' vol. 43 (1899), 

 p. 57; P. A. Levene, < Zeitschr. f. physiol. Chem., vol. 32 (1901), p. 541; W. 

 Jones and G-. H. Whipple, ' Amer. Jour, of Phys.,' vol. 7 (1902), p. 423. See 

 particularly the recent paper by Thomas B. Osborne and Isaac F. Harris, " Die 

 Nxicleinsaure des Weizenembryos," 'Zeitsoh. f. physiol. Chem.,' vol. 36, Heft 2 

 (September, 1902), p. 85. 



t Olof Hammarsten, " Zur Kemitniss der Nucleoproteide," ' Zeitschr. f. physiol. 

 Chem., vol. 19 (1894), p. 19. 



