l-Canavanine Metabolism in Jack Bean, Canavalia ensiformis (L.) DC. (Leguminosae) |
| |
Authors: | Rosenthal G A |
| |
Affiliation: | T. H. Morgan School of Biological Sciences, University of Kentucky, Lexington, Kentucky 40506. |
| |
Abstract: | l-Canavanine, a highly toxic arginine antimetabolite, is the principal nonprotein amino acid of many leguminous plants. Labeled-precursor feeding studies, conducted primarily with [(14)C]carbamoyl phosphate, and utilization of the seedlings of jack bean, Canavalia ensiformis (L.) DC. (Leguminosae), have provided evidence for l-canavanine biosynthesis from l-canaline via O-ureido-l-homoserine. This reaction pathway appears to constitute an important in vivo route of canavanine production. Canavanine cleavage to canaline may represent a degradative phase of canavanine metabolism distinct from the anabolic reactions described above. Thus, while these reactions of canavanine metabolism bear analogy to the mammalian Krebs-Henseleit ornithine-urea cycle, no evidence has been obtained at present for the reutilization of canaline in ureidohomoserine formation. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|