This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Web of Science (22) Citing Articles via Google Scholar Google Scholar Articles by Marques, I. A. Articles by Brodelius, P. E. Search for Related Content PubMed PubMed Citation Articles by Marques, I. A. Articles by Brodelius, P. E. Agricola Articles by Marques, I. A. Articles by Brodelius, P. E.

Metabolism and Enzymology

Elicitor-Induced L-Tyrosine Decarboxylase from Plant Cell Suspension Cultures ¹

II. Partial Characterization

Institute of Biotechnology, ETH Hönggerberg, HPT, CH-8093 Zurich, Switzerland

Properties of purified L-tyrosine decarboxylase (EC 4.1.1.25) from elicitor-induced cell suspension cultures of Eschscholtzia californica Cham. and Thalictrum rugosum Ait. are described. L-Tyrosine decarboxylase is a dimeric enzyme with a molecular weight of 112,600 ± 600 daltons. The isoelectric point was estimated to be at pH 5.2 and pH 5.4 for the enzyme from E. californica and T. rugosum, respectively. The purified enzymes were stabilized in the presence of pyridoxal-5-phosphate. Optimum pH for the enzyme from both plants was found to be 8.4. Enzyme activity was dependent on exogeneously supplied pyridoxal-5-phosphate. The enzyme decarboxylated L-tyrosine and L--3,4-dihydroxyphenylalanine but was inactive toward L-phenylalanine and L-tryptophan. Apparent K_m values of Eschscholtzia- and Thalictrum-decarboxylase for L-tyrosine were 0.25 ± 0.03 and 0.27 ± 0.04 millimolar, respectively. Similar affinities were found for L-3,4-dihydroxyphenylalanine. EschscholtziaL-tyrosine decarboxylase was strongly inhibited by the phenylalanine analogue L--aminooxy--phenylpropionate and largely unaffected by D,L--monofluoromethyl-3,4-dihydroxyphenylalanine and -difluoromethyltyrosine.

This article has been cited by other articles:

				P. J. Facchini, M. Yu, and C. Penzes-Yost Decreased Cell Wall Digestibility in Canola Transformed with Chimeric Tyrosine Decarboxylase Genes from Opium Poppy Plant Physiology, July 1, 1999; 120(3): 653 - 664. [Abstract] [Full Text]

				P. J. Facchini, C. Penzes-Yost, N. Samanani, and B. Kowalchuk Expression Patterns Conferred by Tyrosine/Dihydroxyphenylalanine Decarboxylase Promoters from Opium Poppy Are Conserved in Transgenic Tobacco Plant Physiology, September 1, 1998; 118(1): 69 - 81. [Abstract] [Full Text]