|
Published Papers
The Structure of Fibrous Proteins of the Collagen-Gelatin Group. March 31, 1951 Authors: Linus Pauling, Robert B. Corey
| Title: |
The structure of fibrous proteins of the collagengelatin group |
| Creator: |
Pauling, Linus, 1901- |
| Contributor: |
Corey, Robert |
| Publisher: |
National Academy of Sciences. |
| Date: |
1951-05-00 |
| Subject: |
Proteins -- Structure
|
| Description: |
Proceedings of the National Academy of Sciences Vol. 37, Nos. 5, pp. 272-281. May, 1951. |
| Type: |
Text |
| Format: |
text/plain |
| Language: |
en |
| Identifier: |
paulingcorey6-pg01.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: |
THE STRUCTURE OF FIBROUS PROTEINS OF THE COLLAGEN-GELATIN GROUP BY LINUS PAULING AND ROBERT B. COREY GATES AND CRELLIN LABORATORIES
OF CHEMISTRY,* CALIFORNIA INSTITUTE OF TECHNOLOGY, PASADENA, CALIFORNIA Communicated March 31, 1951 Collagen is a very interesting
protein. It has well-defined mechanical properties (great strength, reversible extensibility through only a small range) that
make it suited to the special purposes to which it is put in the animal body, as in tendon, bone, tusk, skin, the cornea of
the eye, intestinal tissue, and probably rather extensively in reticular structures of cells. During the last thirty years,
following the pioneer work of Herzog and Jancke, a number of investigators have attempted to find the structure of collagen
(and of gelatin, which gives similar x-ray photographs), but no one has previously proposed any precisely described configuration,
nor has attempted to account for the positions and intensities of the x-ray diffraction rnaxima. The diffraction pattern of
collagen and gelatin is characterized by a meridional are at 2.86 A.…28Good reproductions of x-ray photographs have been
published by Astbury.)Âhis arc remains essentially uninfluenced by a change in the source of material or its previous treatment;
Bear found that it varied only between the limits 2.82 A and 2.90 A for 26 samples, ranging from deinineralized mammoth tusk
to plain surgical gut (sheep intestinal submucosa).¨n the other hand, the principal equatorial reflec- tion, which for thoroughly
dried tendon'- corresponds to the spacing 10.4 A, varies greatly in spacing with source and treatment of the material.Å¡t
ordinary humidity it is about 11.5 A, and Bear reported the value 15.5 A for kangaroo tail tendon treated with water. It is
evident that collagen consists of molecules (polypeptide chains) extending along the fiber axis, and rather loosely packed
in parallel orientation.¢t will be pointed out below that the equatorial reflections correspond to a hexagonal packing of
circular cylinders. The 2.56 A fiber-axis spacing suggests that the amide groups of the polypeptide chain are in the cis configuration,
as has been mentioned by Astbury.šstbury has suggested a structure for collagen which bears little resemblance to our structure.)¢f
we accept the configuration of the amide group in a peptide as predicted from x-ray investigations of related simple substances,
and described in our earlier paper (with a single change --we have replaced the value 120° for the C'—N—C angle
by the value 123°, which is suggested by general considerations as a reasonable value for the angle between a single bond
and a bond with about 50 per cent
|
|
