172 COMPOUNDS OF THE PROTEINS 



an extraordinary power of dissolving globulin, it will take up almost 

 its own volume of the thick cake at the bottom of a centrifuge tube; 

 and in ox-serum so saturated there is not a trace of alkali-globulin nor 

 of any ionic protein." 



The phenomena observed by Hardy appear to admit of interpretation 

 by the view that the protein-complex in serum is formed by the union 

 of a number of alkali-protein compounds, the union taking place in a 

 manner analogous to that which occurs between proteins and inorganic 

 salts, protein-acid or protein-base compounds in this instance taking 

 the place of the inorganic salts. The soluble compounds which are 

 thus formed are non-ionic, as evidenced by lack of motion in an 

 electrical field. 



It has been suggested that the tissues and tissue-fluids of the various 

 species of the animal kingdom may owe their specific and individual 

 character to a characteristic structure of the protein-complexes in their 

 tissues or tissue-fluids. We shall have occasion to revert to this possi- 

 bility in a subsequent chapter (Chapter XIV) . 



REFERENCES. 

 GENERAL: 



Robertson: The Physical Chemistry of the Proteins. New York, 1918. 

 MODE OP UNION OF AMINO-ACIDS AND FREE AMINO-GROUPS IN PROTEINS: 



Hofmeister: Ergeb. d. Physiol. 1 Abt., 1902, 1, p. 759. 



Levites: Zeit. f. physiol. Chem., 1904-5, 43, p. 202. Biochem. Zeit., 1909, 20, p. 

 224. 



Van Slyke and Birchard: Jour. Biol. Chem., 1913-14, 16, p. 539\ 

 MODE or UNION OF ACIDS AND BASES WITH PROTEINS: 



Bugarszky and Liebermann: Arch. f. d. ges. Physiol., 1898, 72, p. 51. 



Hardy: Jour, of Physiol., 1905, 33, p. 251. 



Robertson: Jour, of Physical Chem., 1911, 15, p. 521. 



Blasel and Matula: Biochem. Zeit., 1913-1914, 58, p. 417. 



Pauli and Hirschfeld: Ibid., 1914, 62, p. 245. 



Osborne and Leavenworth: Jour. Biol. Chem., 1913, 14, p. 481. 

 PRECIPITATION AND COAGULATION: 



Whetham: Theory of Solution. Cambridge, 1902, pp. 396 and 398. 



Pauli and Handovsky: Biochem. Zeit., 1909, 18, p. 340; 1910, 24, p. 239. 



Robertson: Jour. Biol. Chem., 1911, 9, p. 303. 

 COMPOUNDS OF PROTEINS WITH OTHER PROTEINS: 



Hardy: Jour. Physiol., 1905-6, 33, p. 251, appendix p. 327. 



Hunter: Zeit. physiol. Chem., 1907, 53, p. 526. 



af Ugglas: Biochem. Zeit., 1914, 61, p. 469. 



Schmidt: Jour. Biol. Chem., 1916, 25, p. 63. Univ. of California Pub. Pathology, 

 1916, 2, p. 157. 



