The Arabidopsis thaliana trp5 mutant has a feedback-resistant anthranilate synthase and elevated soluble tryptophan

Plant Physiology
J Li, R L Last

Abstract

The first step of tryptophan biosynthesis is catalyzed by anthranilate synthase (AS), which is normally subject to feedback inhibition by tryptophan. Three independent trp5 mutants defective in the Arabidopsis thaliana AS alpha subunit structural gene ASA1 were identified by selection for resistance to the herbicidal compound 6-methylanthranilate. In all three mutants these biochemical changes are caused by a single amino acid substitution from aspartate to asparagine at residue position 341. Compared with the enzyme from wild-type plants, the tryptophan concentration causing 50% inhibition of AS activity in the trp5 mutant increased nearly 3-fold, the apparent Km for chorismate decreased by approximately 50%, and the apparent Vmax increased 60%. As a consequence of altered AS kinetic properties, the trp5 mutants accumulated 3-fold higher soluble tryptophan than wild-type plants. However, even though the soluble tryptophan levels were increased in trp5 plants, the concentrations of five tryptophan biosynthetic proteins remained unchanged. These data are consistent with the hypothesis that the reaction catalyzed by A. thaliana AS is rate limiting for the tryptophan pathway and that accumulation of tryptophan biosynthetic enzymes...Continue Reading

Citations

Jul 29, 2005·Planta·Natali Rianika Mustafa, Robert Verpoorte
Jul 28, 2012·Molecular Genetics and Genomics : MGG·Dong Sub KimSi-Yong Kang
Jul 23, 2013·Journal of Agricultural and Food Chemistry·Ida WenefridaSteve D Linscombe
Mar 11, 1998·Natural Product Reports·P M Dewick
Dec 5, 1998·The Plant Journal : for Cell and Molecular Biology·R RutherfordP H Masson
Dec 22, 2009·Plant Physiology·Fumio MatsudaKazuki Saito
Dec 19, 2009·Plant Physiology·Réjane PratelliGuillaume Pilot
Jun 1, 1997·Annual Review of Plant Physiology and Plant Molecular Biology·Bonnie Bartel
Feb 9, 2008·Annual Review of Plant Biology·Ruth FinkelsteinCamille Steber
May 20, 1998·Proceedings of the National Academy of Sciences of the United States of America·J Bender, G R Fink
Mar 31, 1999·Proceedings of the National Academy of Sciences of the United States of America·P L ConklinR L Last
Aug 28, 2014·Frontiers of Medicine·Xiaoxuan ZhuShilin Chen
Apr 2, 2015·Proceedings of the National Academy of Sciences of the United States of America·Bing WangJiayang Li
Jun 21, 2011·Trends in Plant Science·Wagner L AraújoAlisdair R Fernie
Dec 25, 2015·Fungal Genetics and Biology : FG & B·Pin-Mei WangNancy P Keller
Jul 6, 2010·The Plant Journal : for Cell and Molecular Biology·Tengfang HuangGeorg Jander
Sep 21, 2013·Molecular Plant·Peter K LundquistAndreas P M Weber

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