J. S. Wolff, J. Ogle, M. A. Logan
Mar 25, 1966
Citations
0
Influential Citations
32
Citations
Journal
The Journal of biological chemistry
Abstract
Abstract The cis and trans racemates of synthetic 3-hydroxyproline and of synthetic 3-methoxyproline were interconverted by an epimerization reaction at carbon atom 2. The interconversions are proof of the diastereomeric nature of the synthetic isomers. Assignments of cis and trans configuration were made from nuclear magnetic resonance studies. Synthetic cis- and trans-3-hydroxy-dl-proline were partially resolved by the action of prolidase. The l isomers were obtained pure and the optical rotation of the trans l isomer was shown to be identical with that of the natural imino acid. Thus carbon 2 of trans-3-hydroxyproline isolated from cattle Achilles tendon collagen is of the l configuration. The cis and trans racemates of 3-methoxyproline were completely resolved by conversion into and column chromatographic separation of diastereoisomeric peptides. The four 3-hydroxyproline isomers were obtained pure from the 3-methoxyproline compounds. Most of the criteria of acceptance of trans-3-hydroxy-l-proline as a new amino acid occurring in a protein are met.