Date of Award:


Document Type:


Degree Name:

Doctor of Philosophy (PhD)


Nutrition, Dietetics, and Food Sciences


Anthony T. Tu


The importance of nucleic acids in plant and animal cells as carriers of genetic information and as protein biosynthesis agents is well recognized. It is also known that nucleic acid is a component of all viruses.

Takahashi (45) and Fraenkel-Conrat (16) demonstrated that the protein component of tobacco mosaic virus is non-infectious to the host plant, although it is identical to the original virus morphologically. The virus ribonucleic acid (RNA) alone was infectious, however.

Deoxyribonucleic acid (DNA), which is present in chromosomes, displays a very specific function. The chromosome long has been accepted as the carrier of the hereditary unit, the gene, whose main component is DNA, which controls the formation of enzymes and of many proteins. Agents that bring about a mutational effect, affect DNA. Some of these agents are ultraviolet light, X-ray radiation and nitrous acid.