Chemical pathology : being a discussion of general pathology from the standpoint of the chemical processes involved / by H. Gideon Wells.

  • Wells, H. Gideon (Harry Gideon), 1875-1943.
Date:
1918
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Licence: In copyright

Credit: Chemical pathology : being a discussion of general pathology from the standpoint of the chemical processes involved / by H. Gideon Wells. Source: Wellcome Collection.

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    susceptibility to poisons of enzymes and cells.1 Strengths of certain antiseptics that will either destroy or inhibit the action of living cells, such as alcohol, ether, salicylic acid, thymol, chloroform, toluene and sodium fluoride, will harm free enzymes in solution little or not at all. This fact has been of great assistance in distinguishing between the action of enzymes and of possible contaminating bacteria in experi- mental work. Although this difference between enzymes and cells is characteristic, it does not finally decide that the cell actions are not enzyme actions, for it may well be that the poisons act chiefly by altering the physical conditions of the cell so that diffusion is inter- fered with, thus seriously interfering with the exchange of cleavage products between different parts of the cell, and checking intracellu- lar enzyme action, which we shall see later requires free diffusion of the products for its continuance. At the very least, however, we may look upon the intracellular enzymes as the most important known agents of cell metabolism, and consequently of all life manifestations, and the changes they undergo or produce in pathological conditions must be fully as fundamentally important as is their relation to physiological processes. It therefore becomes necessary for us to consider carefully— THE NATURE OF ENZYMES AND THEIR ACTIONS 2 Since up to the present time no ferment has been isolated in an absolutely pure condition we are entirely unfamiliar with their chemi- cal characters, and consequently are obliged to recognize them solely by their action. As far as we know, true enzymes never occur except as the result of cell life—they are produced within the cell, and in- creased in amount by each new cell that is formed, and, furthermore, they are present in every living cell without exception. As the same facts are equally true of the proteins, and apparently true of nothing else, it is natural to associate the enzymes with proteins, and so ex- plain the importance of the proteins for cell life.3 If enzymes are obtained in any of the usual ways from animal cells or secretions they are always found to give the reactions for proteins, even if re- purified many times. But it is well known that whenever proteins are precipitated the other substances in the solution tend to be dragged 1 See discussion by Vernon, Ergebnisse d. Physiol., 1910 (9), 234. 2 It would not be profitable to discuss fully all the various theories and hy- potheses that have been advanced, but the reader is referred to the following chief compilations of the entire subject: Oppenheimer, “Die Fermente und ihre Wirk- ungen,” Leipzig; Bayliss, “The Nature of Enzyme Action,” Monographs on Bio- chemistry, London: Stern, “Physico-chemical Basis of Ferment Action,” in Oppen- heimer’s “Handbuch d. Biochemie,” Vol. 4, pt. 2; Samueley, “Animal Ferments,” ibid, Vol. I; A. E. Taylor, “On Fermentation,” Univ. of California Publications; Euler, “General Chemistry of the Enzymes,” translated by T. H. Pope, New York, 1912. s Another important point is that the closest imitation of enzymes, Bredig’s “inorganic ferments,” seem to owe their action to their colloidal nature.