MOLECULAR STRUCTURE OF NUCLEIC ACID


A structure for Deoxyribose Nucleic Acid


We wish to suggest a structure for the salt of deoxyribose nucleic acid (D.N.A.).

This structure has novel features which are of considerable biological interest.(..)

We wish to put forward a radically different structure for the salt of deoxyribose nucleic acid.

This structure has two helical chains each coiled round the same axis.

The novel feature of the structure is the manner in which the two chains are held together by the purine and pyrimidne bases.

They are joined togethe in pairs, these pairs are: adenine (purine) wit thymine (pyrimidine), and guanine (purine) with cytosine (pyrimidine).

In other words, if an adenine forms one member of a pair, on either chain, then on these assumptions the other member must be thymine; similarly for guanine and cytosine.

It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.

We have also been stimulated by a knowledge of the general nature of the published experimental results and ideas of Dr. M. H. F. Wilkins, Dr. R. E. Franklin and their co-workers at King's College, London.

One of us (J.D.W.) has been aided by a fellowship from the National Foundation for Infantile Paralysis.


J.D. Watson
F.H.C. Crick

Medical Research Council Unit for the
Study of the Molecular Structure of
Biological Systems,
Cavendish Laboratory, Cambridge,
April 2 1953.

This text is an our summary from the original text.

 

These pctures from the site:

http://www.chemheritage.org/EducationalServices/chemach/ppb/cwwf.html