Some problems of intermediary metabolism.

  • Chittenden, R. H. (Russell Henry), 1856-1943.
Date:
[1905]
Catalogue details

Licence: Public Domain Mark

Credit: Some problems of intermediary metabolism. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    be transformed into sugar or glycogen. In alkaptonuria, however, while deamidization of alanin may occur as nor- mally, oxidation and other changes stop at the uroleucic or homogentisic acid stage, the body cells having lost the power of splitting off or burning the benzol ring ; an anom- aly in intermediary metabolism without doubt due to the absence or inhibition of the specific intra-cellular enzyme which normally accomplishes this transformation. And so we see on every hand in studying the many and varied processes of intermediary metabolism, of which the foregoing are to be taken merely as illustrations, the sig- nificant part played by intra-cellular enzymes in bringing about the normal and abnormal changes characteristic of health and disease.* The processes which we have hereto- fore considered as due to the peculiar vital properties of the tissue cells, and which were supposed to be entirely dependent upon their morphological and functional integrity, we now see are due — certainly in large measure, if not wholly — to a great variety of enzymes which can be sep- arated from the cell substance and which retain their activity even when free from the influence of the living protoplasm. Further, we find ample evidence that the varied processes of katabolism are the result of orderly chemical changes, of :i progressive character, in which cleavage, hydration, re- duction, oxidation, deamidization, etc., alternate with each other under the influence of specific enzymes, where chemi- cal constitution and stereochemical configuration of the va- rious molecules are determining factors in the changes produced. It is therefore evident that our understanding of intermediary metabolism will depend in large measure upon the intelligent application of the principles and methods of physiological chemistry in our study of these important and far-reaching problems. ,M: Die Bedeutung det intraceUaULren Enzyme in der BiochemUchea Centralblatt, Band ■'>, p. 886.