Skip to main content
PMC home page
Plant Physiology logoLink to Plant Physiology
. 1968 Aug;43(8):1227–1231. doi: 10.1104/pp.43.8.1227

Metabolism of Cytidine and Uridine in Bean Leaves 1

Cleon Ross 1, C V Cole 1,2
PMCID: PMC1086998  PMID: 16656905

Abstract

The metabolism of cytidine-2-14C and uridine-2-14C was studied in discs cut from leaflets of bean plants (Phaseolus vulgaris L.). Cytidine was degraded to carbon dioxide and incorporated into RNA at about the same rates as was uridine. Both nucleosides were converted into the same soluble nucleotides, principally uridine diphosphate glucose, suggesting that cytidine was rapidly deaminated to uridine and then metabolized along the same pathways. However, cytidine was converted to cytidine diphosphate and cytidine triphosphate more effectively than was uridine. Cytidine also was converted into cytidylic acid of RNA much more extensively and into RNA uridylic acid less extensively than was uridine. Azaserine, an antagonist of reactions involving glutamine (including the conversion of uridine triphosphate to cytidine triphosphate), inhibited the conversion of cytidine into RNA uridylic acid with less effect on its incorporation into cytidylic acid. On the other hand, it inhibited the conversion of orotic acid into RNA cytidylic acid much more than into uridylic acid. The results suggest that cytidine is in part metabolized by direct conversion to uridine and in part by conversion to cytidine triphosphate through reactions not involving uridine nucleotides.

Full text

PDF
1227

Images in this article

1229Image
on p.1229

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Achar B. S., Maller R. K., Vaidyanathan C. S. Purification & properties of cytosine nucleoside deaminase from green gram (Phaseolus aureus) seedlings. Indian J Biochem. 1966 Sep;3(3):133–138. [PubMed] [Google Scholar]
  2. BRAWERMAN G. A PROCEDURE FOR THE ISOLATION OF RNA FRACTIONS RESEMBLING DNA WITH RESPECT TO NUCLEOTIDE COMPOSITION. Biochim Biophys Acta. 1963 Oct 15;76:322–324. [PubMed] [Google Scholar]
  3. Bandurski R. S., Maheshwari S. C. Nucleotide Incorporation Into Nucleic Acid by Tobacco Leaf Homogenates. Plant Physiol. 1962 Jul;37(4):556–560. doi: 10.1104/pp.37.4.556. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Barker G. R., Hollinshead J. A. The degradation of ribonucleic acid in the cotyledons of Pisum arvense. Biochem J. 1967 Apr;103(1):230–237. doi: 10.1042/bj1030230. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Cole C. V., Ross C. Extraction, separation, and quantitative estimation of soluble nucleotides and sugar phosphates in plant tissues. Anal Biochem. 1966 Dec;17(3):526–539. doi: 10.1016/0003-2697(66)90188-6. [DOI] [PubMed] [Google Scholar]
  6. Frisch D. M., Charles M. A. Deamination of 4-aminopyrimidine nucleosides by extracts of rye grass (Lolium perenne). Plant Physiol. 1966 Mar;41(3):475–478. doi: 10.1104/pp.41.3.475. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. KAMMEN H. O., HURLBERT R. B. The formation of cytidine nucleotides and RNA cytosine from orotic acid by the Novikoff tumor in vitro. Cancer Res. 1959 Jul;19(6 Pt 1):654–663. [PubMed] [Google Scholar]
  8. LIEBERMAN I. Enzymatic amination of uridine triphosphate to cytidine triphosphate. J Biol Chem. 1956 Oct;222(2):765–775. [PubMed] [Google Scholar]
  9. Long C. W., Pardee A. B. Cytidine triphosphate synthetase of Escherichia coli B. I. Purification and kinetics. J Biol Chem. 1967 Oct 25;242(20):4715–4721. [PubMed] [Google Scholar]
  10. Ross C. Comparison of incorporation and metabolism of RNA pyrimidine nucleotide precursors in leaf tissues. Plant Physiol. 1965 Jan;40(1):65–73. doi: 10.1104/pp.40.1.65. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Wang D. Biosynthesis of nucleotides in wheat. IV. Metabolism of specifically 14-C-labeled orotic acid. Can J Biochem. 1967 May;45(5):721–728. doi: 10.1139/o67-082. [DOI] [PubMed] [Google Scholar]
  12. Wanka F. Properties of uridine and thymidine phosphorylating enzymes of Zea mays. Z Naturforsch B. 1967 Jan;22(1):91–96. doi: 10.1515/znb-1967-0117. [DOI] [PubMed] [Google Scholar]
  13. Wasilewska L. D., Reifer I. Uracil and uridine as precursors of pyrimidine nucleotides in higher plants. Acta Biochim Pol. 1967;14(1):41–56. [PubMed] [Google Scholar]
  14. Wolcott J. H., Ross C. Orotidine-5'-phosphate decarboxylase and pyrophosphorylase of bean leaves. Plant Physiol. 1967 Feb;42(2):275–279. doi: 10.1104/pp.42.2.275. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Plant Physiology are provided here courtesy of Oxford University Press

RESOURCES