Publications [#229269] of Thomas Mitchell-Olds

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Papers Published

  1. Kroymann, J; Textor, S; Tokuhisa, JG; Falk, KL; Bartram, S; Gershenzon, J; Mitchell-Olds, T, A gene controlling variation in Arabidopsis glucosinolate composition is part of the methionine chain elongation pathway., Plant Physiology, vol. 127 no. 3 (November, 2001), pp. 1077-1088 [11706188], [doi] .
    (last updated on 2019/07/22)

    Arabidopsis and other Brassicaceae produce an enormous diversity of aliphatic glucosinolates, a group of methionine (Met)-derived plant secondary compounds containing a beta-thio-glucose moiety, a sulfonated oxime, and a variable side chain. We fine-scale mapped GSL-ELONG, a locus controlling variation in the side-chain length of aliphatic glucosinolates. Within this locus, a polymorphic gene was identified that determines whether Met is extended predominantly by either one or by two methylene groups to produce aliphatic glucosinolates with either three- or four-carbon side chains. Two allelic mutants deficient in four-carbon side-chain glucosinolates were shown to contain independent missense mutations within this gene. In cell-free enzyme assays, a heterologously expressed cDNA from this locus was capable of condensing 2-oxo-4-methylthiobutanoic acid with acetyl-coenzyme A, the initial reaction in Met chain elongation. The gene methylthioalkylmalate synthase1 (MAM1) is a member of a gene family sharing approximately 60% amino acid sequence similarity with 2-isopropylmalate synthase, an enzyme of leucine biosynthesis that condenses 2-oxo-3-methylbutanoate with acetyl-coenzyme A.