The basic character of the protein molecule and the reactions of edestin with definite quantities of acids and alkalies.

  • Osborne, Thomas B. (Thomas Burr), 1859-1929.
Date:
[1900]
Catalogue details

Licence: In copyright

Credit: The basic character of the protein molecule and the reactions of edestin with definite quantities of acids and alkalies. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    tinormal solution per gram, is very sparingly soluble in water. It is this salt which forms the so-called “albuminate” found in edestin preparations. If edestan has a molecular weight near that of edestin, assumed to be about 14,500 (see Osborne, Jour. Amer. Chem. Soc. 21, 486, 1899; also the paper following), this acidity would correspond to that of a trichloride, being just three times that of edestin monochloride and one and one-half times that of the bichloride. Edestan is insoluble in water, far less soluble in solutions of potassium hydrate than is edestin and insoluble in ammonia water, unless the solution of the latter is relatively very strong. The aqueous solution of edestan chloride, when concen- trated, reacts acid with litmus. It is precipitated by neutraliza- tion, the precipitate being soluble in strong ammonia, yielding a solution which is precipitated by ammonium chloride but not by sodium chloride. The aqueous solution of edestan chloride gives a precipitate with nitric acid which dissolves on warming and reappears on cooling; a precipitate with ovalbumin solutions, with the alkaloidal reagents and with sufficient mercuric chloride if its solution is concentrated. These reactions agree closely with those given Kossel as characteristic of histons, but with the true histons edestan has little in common. THE BASIC CHARACTER OF THE PROTEIN MOLE- CULE AND THE REACTIONS OF EDESTIN WITH DEFINITE QUANTITIES OF ACIDS AND ALKALIES. By Thomas B. Osborne. I. INTRODUCTION. The Basic Character of the Protein Molecule. That the proteins are ionized and highly reactive bodies is indicated by the rapidity with which they unite with both bases and acids, by the readiness with which, in many cases, they respond to changes in the ionization of their solutions, and also by the fact that they are, chemically, the most active constituents of protoplasm.