Published Papers

Molecular Architecture and the Processes of Life. May 28, 1948.

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Title:	Molecular Architecture and the Processes of Life [5 of 15]
Creator:	Pauling, Linus, 1901-
Publisher:	Nature.
Date:	1948-05-28
Subject:	Molecular structure
Description:	Nature, vol. 248. Original typescript.
Type:	Text
Format:	text/plain
Language:	en
Identifier:	jessebootlecture-pg05.jpg
Source:	Master scanned with Epson GT-10000+ flatbed scanner at 600 dpi.
Rights:	http://osulibrary.orst.edu/specialcollections/coll/pauling/dna/copyright.html
Full Text:	oxidation of this material. It is usually necessary to light a fire, in order to raise the temperature high enough for the process of oxidation to go on. The body operates at body temperature, 95.6°F., by having developed some ways of causing this burning to go on even at this relatively low temperature. These ways involve giant molecules, enzymes, with 10,000 or 20,000 or more atoms per molecule, which have the ability of causing chemical reactions to go on at lower temperatures than in the absence of the enzymes. The body contains many special enzymes connected with the oxidation of the break- down products of foodstuffs in the body, and %with the oxidation of the parts of the body itself that are no longer needed. Just as hemoglobin has the specific ability of combining with oxygen and carrying it from the lungs to the tissues, so do the various enzymes have the specific ability of oxidizing certain materials. In general each enzyme has one use : it catalyzes one reaction of the many thousands of reactions that take place in the living body. Moreover, it is giant molecules, presumably molecules of nucleoprotein, that determine the characters of individual living organisms and that are involved in the transmission of these characters to their progeny. These giant molecules are the genes, which are usually present in structures in the cell called chromosomes. The Gregorian monk Mendel noted that the inheritance of characters by pea plants, such as the character of tallness or of dwarfness, or the character of having purple flowers or white flowers, could be understood on the basis of hereditary units transmitted from the parent to the offspring. Thomas Hunt Morgan and his collaborators identified these units with genes arranged in a linear array- in the chromosomes. They have determined the arrangement of several hundreds of these genes in the chromosomes of the vinegar fly, Drosophila ncelanogaster, and it is likely that even this very small organism has many more than this number of genes, probably as many as 20,000.