6CD0

Crystal structure of Medicago truncatula serine hydroxymethyltransferase 3 (MtSHMT3), PLP-internal aldimine and apo form

6CD0 の概要

• エントリーDOI: 10.2210/pdb6cd0/pdb
• 分子名称: Serine hydroxymethyltransferase, ACETATE ION, FORMIC ACID, ... (5 entities in total)
• 機能のキーワード: plp, one-carbon cycle, tetrahydrofolate, chloroplast, tetramer, transferase
• 由来する生物種: Medicago truncatula (Barrel medic); 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 199399.46

構造登録者

Ruszkowski, M.,Sekula, B.,Ruszkowska, A.,Dauter, Z. (登録日: 2018-02-07, 公開日: 2018-05-23, 最終更新日: 2023-11-15)

主引用文献

Ruszkowski, M.,Sekula, B.,Ruszkowska, A.,Dauter, Z.
Chloroplastic Serine Hydroxymethyltransferase FromMedicago truncatula: A Structural Characterization.
Front Plant Sci, 9:584-584, 2018

PubMed Abstract: Serine hydroxymethyltransferase (SHMT, EC 2.1.2.1) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme which catalyzes the reversible serine-to-glycine conversion in either a tetrahydrofolate-dependent or -independent manner. The enzyme is also responsible for the tetrahydrofolate-independent cleavage of other β-hydroxy amino acids. In addition to being an essential player in the serine homeostasis, SHMT action is the main source of activated one-carbon units, which links SHMT activity with the control of cell proliferation. In plants, studies of SHMT enzymes are more complicated than of those of, e.g., bacterial or mammalian origins because plant genomes encode multiple SHMT isozymes that are targeted to different subcellular compartments: cytosol, mitochondria, plastids, and nucleus. Here we report crystal structures of chloroplast-targeted SHMT from (SHMT3). SHMT3 is a tetramer in solution, composed of two tight and obligate dimers. Our complexes with PLP internal aldimine, PLP-serine and PLP-glycine external aldimines, and PLP internal aldimine with a free glycine reveal structural details of the SHMT3-catalyzed reaction. Capturing the enzyme in different stages along the course of the slow tetrahydrofolate-independent serine-to-glycine conversion allowed to observe a unique conformation of the PLP-serine γ-hydroxyl group, and a concerted movement of two tyrosine residues in the active site.

PubMed: 29868052
DOI: 10.3389/fpls.2018.00584

実験手法

X-RAY DIFFRACTION (1.74 Å)