This Article  • References  • Full text PDF  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citation map  • Contact me when this article is cited  Related Content  • Similar articles in JAMA  Social Bookmarking   What's this?

J Am Med Assoc. 1933;100(9):665-666.

	Since this article does not have an abstract, we have provided the first 150 words of the full text PDF and any section headings.

A little over a hundred years ago, Kirchoff observed that malt diastase brought about the same change in starch as was produced by heating with acid and that the hydrolytic agent, in one instance the diastase and in the other the acid, apparently remained unchanged at the end of the reaction. In the intervening years, enzymes have been looked on as catalysts, substances that do not initiate or take a permanent part in the reaction but whose presence exerts an influence on the speed of the chemical change. They are considered to be organic in nature, produced only by living cells but not requiring the presence of the cells for their activity. Few, if any, of the chemical changes occurring in living organisms are independent of the influence of enzymes; indeed, it has been stated¹ that "we may regard life as a system of cooperating enzymatic reactions." It is . . . [Full Text PDF of this Article]

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter     What's this?