6E1J

Crystal Structure of Methylthioalkylmalate Synthase (BjuMAM1.1) from Brassica juncea

Summary for 6E1J

• Entry DOI: 10.2210/pdb6e1j/pdb
• Descriptor: 2-isopropylmalate synthase, A genome specific 1, MANGANESE (II) ION, 4-(METHYLSULFANYL)-2-OXOBUTANOIC ACID, ... (5 entities in total)
• Functional Keywords: x-ray crystal structure, enzyme, methylthioalkylmalate synthase, plant protein
• Biological source: Brassica juncea (Indian mustard)
• Total number of polymer chains: 2
• Total formula weight: 112906.11

Authors

Lee, S.G.,Jez, J.M. (deposition date: 2018-07-09, release date: 2019-05-08, Last modification date: 2024-10-30)

Primary citation

Kumar, R.,Lee, S.G.,Augustine, R.,Reichelt, M.,Vassao, D.G.,Palavalli, M.H.,Allen, A.,Gershenzon, J.,Jez, J.M.,Bisht, N.C.
Molecular Basis of the Evolution of Methylthioalkylmalate Synthase and the Diversity of Methionine-Derived Glucosinolates.
Plant Cell, 31:1633-1647, 2019

PubMed Abstract: The globally cultivated species possess diverse aliphatic glucosinolates, which are important for plant defense and animal nutrition. The committed step in the side chain elongation of methionine-derived aliphatic glucosinolates is catalyzed by methylthioalkylmalate synthase, which likely evolved from the isopropylmalate synthases of leucine biosynthesis. However, the molecular basis for the evolution of methylthioalkylmalate synthase and its generation of natural product diversity in is poorly understood. Here, we show that genomes encode multiple methylthioalkylmalate synthases that have differences in expression profiles and 2-oxo substrate preferences, which account for the diversity of aliphatic glucosinolates across accessions. Analysis of the 2.1 Å resolution x-ray crystal structure of methylthioalkylmalate synthase identified key active site residues responsible for controlling the specificity for different 2-oxo substrates and the determinants of side chain length in aliphatic glucosinolates. Overall, these results provide the evolutionary and biochemical foundation for the diversification of glucosinolate profiles across globally cultivated species, which could be used with ongoing breeding strategies toward the manipulation of beneficial glucosinolate compounds for animal health and plant protection.

PubMed: 31023839
DOI: 10.1105/tpc.19.00046

Experimental method

X-RAY DIFFRACTION (2.096 Å)