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. 1968 Jul;43(7):1141–1145. doi: 10.1104/pp.43.7.1141

Studies on Auxin Protectors. V. On the Mechanism of IAA Protection by Protector-I of the Japanese Morning Glory

Tom Stonier 1, Yoshiaki Yoneda 1,1, Felix Rodriguez-Tormes 1
PMCID: PMC1086986  PMID: 16656896

Abstract

The mechanism of auxin protection by auxin protector-I (Pr-I) of the Japanese morning glory was studied in vitro. Four lines of evidence indicate that Pr-I acts as a strong reductant which prevents the peroxidase-catalyzed oxidation of IAA: 1) The kinetics of the reaction are best explained on this basis. 2) The Pr-I-induced lag preceding auxin destruction by peroxidase is completely eliminated by a strong oxidant such as H2O2 at a concentration which does not appreciably affect the reaction rate. 3) Strong organic reductants mimic the Pr-I-induced lag. And 4) when the reaction rate is altered by varying the concentrations of the reactants, or the temperature, the length of the Pr-I-induced lag varies inversely with the reaction rate.

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Selected References

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

  1. CLELAND W. W. DITHIOTHREITOL, A NEW PROTECTIVE REAGENT FOR SH GROUPS. Biochemistry. 1964 Apr;3:480–482. doi: 10.1021/bi00892a002. [DOI] [PubMed] [Google Scholar]
  2. Fox L. R., Purves W. K., Nakada H. I. The role of horseradish peroxidase in indole-3-acetic acid oxidation. Biochemistry. 1965 Dec;4(12):2754–2763. doi: 10.1021/bi00888a028. [DOI] [PubMed] [Google Scholar]
  3. HINMAN R. L., LANG J. PEROXIDASE-CATALYZED OXIDATION OF INDOLE-3-ACETIC ACID. Biochemistry. 1965 Jan;4:144–158. doi: 10.1021/bi00877a023. [DOI] [PubMed] [Google Scholar]
  4. Meudt W. J. Studies on the oxidation of indole-3-acetic acid by peroxidase enzymes. Ann N Y Acad Sci. 1967 Aug 9;144(1):118–128. doi: 10.1111/j.1749-6632.1967.tb34006.x. [DOI] [PubMed] [Google Scholar]
  5. Morgan P. W., Joham H. E., Amin J. V. Effect of manganese toxicity on the indoleacetic Acid oxidase system of cotton. Plant Physiol. 1966 Apr;41(4):718–724. doi: 10.1104/pp.41.4.718. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Stonier T., Rodriguez-Tormes F., Yoneda Y. Studies on Auxin Protectors. IV. The Effect of Manganese on Auxin Protector-I of the Japanese Morning Glory. Plant Physiol. 1968 Jan;43(1):69–72. doi: 10.1104/pp.43.1.69. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. WAGENKNECHT A. C., BURRIS R. H. Indoleacetic acid inactivating enzymes from bean roots and pea seedlings. Arch Biochem. 1950 Jan;25(1):30–53. [PubMed] [Google Scholar]
  8. YAMAZAKI I., MASON H. S., PIETTE L. Identification, by electron paramagnetic resonance spectroscopy, of free radicals generated from substrates by peroxidase. J Biol Chem. 1960 Aug;235:2444–2449. [PubMed] [Google Scholar]
  9. Yoneda Y., Stonier T. Distribution of Three Auxin Protector Substances in Seeds and Shoots of the Japanese Morning Glory (Pharbitis nil). Plant Physiol. 1967 Jul;42(7):1017–1020. doi: 10.1104/pp.42.7.1017. [DOI] [PMC free article] [PubMed] [Google Scholar]

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