![]() |
|
|
Department of Biochemistry, School of Medicine, University of North Carolina, Chapel Hill, NC 27514
The many enzyme reactions involved in the interconversion of glutamate, ornithine, proline and arginine are interrelated to one another by the metabolite pyrroline-5-carboxylate. This chemical is synthesized de novo from glutamate by the intestinal mucosa and to a lesser degree by the thymus. Pyrroline-5-carboxylate can be metabolized to ornithine (and arginine), proline and glutamate. Several futile cycles could exist because of the common utilization of pyrroline-5-carboxylate for these pathways. This does not appear to occur because of the tissue distribution of these enzymes, the various isozymes of the enzymes that may have different regulatory or kinetic properties and amino acid transport systems that differ from tissue to tissue.
KEY WORDS: glutamate ornithine proline pyrroline-5-carboxylate
Manuscript received 17 October 1984.
This article has been cited by other articles:
![]() |
R. F. Bertolo and D. G. Burrin Comparative Aspects of Tissue Glutamine and Proline Metabolism J. Nutr., October 1, 2008; 138(10): 2032S - 2039S. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. O. Ball, K. L. Urschel, and P. B. Pencharz Nutritional Consequences of Interspecies Differences in Arginine and Lysine Metabolism J. Nutr., June 1, 2007; 137(6): 1626S - 1641S. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. F. P. Bertolo, J. A. Brunton, P. B. Pencharz, and R. O. Ball Arginine, ornithine, and proline interconversion is dependent on small intestinal metabolism in neonatal pigs Am J Physiol Endocrinol Metab, May 1, 2003; 284(5): E915 - E922. [Abstract] [Full Text] [PDF] |
||||