5VOO

Methionine synthase folate-binding domain with methyltetrahydrofolate from Thermus thermophilus HB8

5VOO の概要

• エントリーDOI: 10.2210/pdb5voo/pdb
• 関連するPDBエントリー: 5VON 5VOP
• 分子名称: 5-methyltetrahydrofolate homocysteine S-methyltransferase, 5-METHYL-5,6,7,8-TETRAHYDROFOLIC ACID, SODIUM ION, ... (7 entities in total)
• 機能のキーワード: methyltransferase, pterin binding, b12 binding, oxidoreductase, transferase
• 由来する生物種: Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579)
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 201458.32

構造登録者

Koutmos, M.,Yamada, K. (登録日: 2017-05-03, 公開日: 2018-01-17, 最終更新日: 2023-10-04)

主引用文献

Yamada, K.,Koutmos, M.
The folate-binding module of Thermus thermophilus cobalamin-dependent methionine synthase displays a distinct variation of the classical TIM barrel: a TIM barrel with a `twist'.
Acta Crystallogr D Struct Biol, 74:41-51, 2018

PubMed Abstract: Methyl transfer between methyltetrahydrofolate and corrinoid molecules is a key reaction in biology that is catalyzed by a number of enzymes in many prokaryotic and eukaryotic organisms. One classic example of such an enzyme is cobalamin-dependent methionine synthase (MS). MS is a large modular protein that utilizes an S2-type mechanism to catalyze the chemically challenging methyl transfer from the tertiary amine (N5) of methyltetrahydrofolate to homocysteine in order to form methionine. Despite over half a century of study, many questions remain about how folate-dependent methyltransferases, and MS in particular, function. Here, the structure of the folate-binding (Fol) domain of MS from Thermus thermophilus is reported in the presence and absence of methyltetrahydrofolate. It is found that the methyltetrahydrofolate-binding environment is similar to those of previously described methyltransferases, highlighting the conserved role of this domain in binding, and perhaps activating, the methyltetrahydrofolate substrate. These structural studies further reveal a new distinct and uncharacterized topology in the C-terminal region of MS Fol domains. Furthermore, it is found that in contrast to the canonical TIM-barrel βα fold found in all other folate-binding domains, MS Fol domains exhibit a unique βα fold. It is posited that these structural differences are important for MS function.

PubMed: 29372898
DOI: 10.1107/S2059798317018290

実験手法

X-RAY DIFFRACTION (2.4 Å)