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Title: Molecular basis of the evolution of alternative tyrosine biosynthetic routes in plants

Abstract

L-Tyrosine (Tyr) is essential for protein synthesis and is a precursor of numerous specialized metabolites crucial for plant and human health. Tyr can be synthesized via two alternative routes by different key regulatory TyrA family enzymes, prephenate dehydrogenase (PDH, also known as TyrAp) or arogenate dehydrogenase (ADH, also known as TyrAa), representing a unique divergence of primary metabolic pathways. The molecular foundation underlying the evolution of these alternative Tyr pathways is currently unknown. Here we characterized recently diverged plant PDH and ADH enzymes, obtained the X-ray crystal structure of soybean PDH, and identified a single amino acid residue that defines TyrA substrate specificity and regulation. Structures of mutated PDHs co-crystallized with Tyr indicate that substitutions of Asn222 confer ADH activity and Tyr sensitivity. Reciprocal mutagenesis of the corresponding residue in divergent plant ADHs further introduced PDH activity and relaxed Tyr sensitivity, highlighting the critical role of this residue in TyrA substrate specificity that underlies the evolution of alternative Tyr biosynthetic pathways in plants.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
National Science Foundation (NSF)
OSTI Identifier:
1377912
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Chemical Biology; Journal Volume: 13; Journal Issue: 9
Country of Publication:
United States
Language:
ENGLISH

Citation Formats

Schenck, Craig A., Holland, Cynthia K., Schneider, Matthew R., Men, Yusen, Lee, Soon Goo, Jez, Joseph M., and Maeda, Hiroshi A. Molecular basis of the evolution of alternative tyrosine biosynthetic routes in plants. United States: N. p., 2017. Web. doi:10.1038/nchembio.2414.
Schenck, Craig A., Holland, Cynthia K., Schneider, Matthew R., Men, Yusen, Lee, Soon Goo, Jez, Joseph M., & Maeda, Hiroshi A. Molecular basis of the evolution of alternative tyrosine biosynthetic routes in plants. United States. doi:10.1038/nchembio.2414.
Schenck, Craig A., Holland, Cynthia K., Schneider, Matthew R., Men, Yusen, Lee, Soon Goo, Jez, Joseph M., and Maeda, Hiroshi A. Mon . "Molecular basis of the evolution of alternative tyrosine biosynthetic routes in plants". United States. doi:10.1038/nchembio.2414.
@article{osti_1377912,
title = {Molecular basis of the evolution of alternative tyrosine biosynthetic routes in plants},
author = {Schenck, Craig A. and Holland, Cynthia K. and Schneider, Matthew R. and Men, Yusen and Lee, Soon Goo and Jez, Joseph M. and Maeda, Hiroshi A.},
abstractNote = {L-Tyrosine (Tyr) is essential for protein synthesis and is a precursor of numerous specialized metabolites crucial for plant and human health. Tyr can be synthesized via two alternative routes by different key regulatory TyrA family enzymes, prephenate dehydrogenase (PDH, also known as TyrAp) or arogenate dehydrogenase (ADH, also known as TyrAa), representing a unique divergence of primary metabolic pathways. The molecular foundation underlying the evolution of these alternative Tyr pathways is currently unknown. Here we characterized recently diverged plant PDH and ADH enzymes, obtained the X-ray crystal structure of soybean PDH, and identified a single amino acid residue that defines TyrA substrate specificity and regulation. Structures of mutated PDHs co-crystallized with Tyr indicate that substitutions of Asn222 confer ADH activity and Tyr sensitivity. Reciprocal mutagenesis of the corresponding residue in divergent plant ADHs further introduced PDH activity and relaxed Tyr sensitivity, highlighting the critical role of this residue in TyrA substrate specificity that underlies the evolution of alternative Tyr biosynthetic pathways in plants.},
doi = {10.1038/nchembio.2414},
journal = {Nature Chemical Biology},
number = 9,
volume = 13,
place = {United States},
year = {Mon Jun 26 00:00:00 EDT 2017},
month = {Mon Jun 26 00:00:00 EDT 2017}
}
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