Transfer RNA-Peroxidase Interaction: INHIBITION OF INDOLE-3-ACETIC ACID OXIDATION
AUTOR(ES)
Lee, Tsung T.
RESUMO
Transfer RNA from wheat germ, yeast, and Escherichia coli inhibited the indoleacetic acid (IAA)-induced spectral change in horseradish peroxidase (EC 1.11.1.7) and the decarboxylation of IAA. The inhibition was limited to a delay after which the increase in A427 and the decarboxylation of IAA resumed at the same rate as in the control; the duration of the inhibition was dependent on, but not proportional to, the concentration of tRNA. Alkaline hydrolysis destroyed the inhibitory activity of tRNA. The inhibition was completely abolished when the tRNA was added 30 seconds after IAA. Thus, the tRNA appears not to react with the enzyme intermediates formed during the reaction with IAA. The inhibition by tRNA was rapidly reversed by H2O2 or additional IAA, but not by 2,4-dichlorophenol. Results suggest that the tRNA interferes with the initial reaction between IAA and the heme moiety of free peroxidase, thus preventing the formation of highly active enzyme intermediates essential for IAA degradation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=440770Documentos Relacionados
- Oxidation of Indole-3-Acetic Acid-Amino Acid Conjugates by Horseradish Peroxidase
- Indole-3-Acetic Acid Oxidation and Crocin Bleaching by Horseradish Peroxidase 1
- Hydrogen Peroxide-mediated Oxidation of Indole-3-acetic Acid by Tomato Peroxidase and Molecular Oxygen 1
- Inhibition of Polar Indole-3-acetic Acid Transport by Cycloheximide
- Proposed Model for the Peroxidase-Catalyzed Oxidation of Indole-3-acetic Acid in the Presence of the Inhibitor Ferulic Acid 1