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Phytohormones: Structure and physiological activity. I

Koepfli, J. B. and Thimann, Kenneth V. and Went, F. W. (1938) Phytohormones: Structure and physiological activity. I. Journal of Biological Chemistry, 122 (3). pp. 763-780. ISSN 0021-9258.

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In plants, growth in length by cell elongation is conditioned by certain substances elaborated in the plant and effective in minute amounts, thus having the nature of hormones. A number of simple tests have been worked out which allow of a qualitative and quantitative determination of the growth-promoting properties of various substances. With the aid of these biological tests the native growth substances or auxins have been isolated and a variety of other substances have been shown to possess growth activity. At first sight the large number of substances which are active do not appear to fall within any general classification. Upon further investigation, however, it becomes clear that there are certain common structural characteristics, and an analysis of these provides a first step in attacking the fundamental problem of the relations between chemical structure and physiological activity. This relation has in recent years been attacked in a number of other fields, usually involving physiological processes in animals. On the other hand, it would appear that plants offer an exceptionally favorable field for study in that their structures--- and possibly their physiological processes-are somewhat less complicated. Thus, it has been found possible to differentiate between some of the steps in the chain of reactions which lead to cell elongation, so that now it becomes possible to determine the exact structure required in a substance for the regulation of each of these steps.

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Additional Information:© 1938 American Society for Biochemistry and Molecular Biology.
Issue or Number:3
Record Number:CaltechAUTHORS:20140917-131738890
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:49785
Deposited By: Tony Diaz
Deposited On:18 Sep 2014 02:57
Last Modified:03 Oct 2019 07:17

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