1IID

Crystal Structure of Saccharomyces cerevisiae N-myristoyltransferase with Bound S-(2-oxo)pentadecylCoA and the Octapeptide GLYASKLA

1IID の概要

• エントリーDOI: 10.2210/pdb1iid/pdb
• 関連するPDBエントリー: 2NMT
• 分子名称: Peptide N-myristoyltransferase, Octapeptide GLYASKLA, NICKEL (II) ION, ... (5 entities in total)
• 機能のキーワード: transferase
• 由来する生物種: Saccharomyces cerevisiae (baker's yeast); 詳細
• 細胞内の位置: Cytoplasm: P14743
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 50946.24

構造登録者

Farazi, T.A.,Gordon, J.I.,Waksman, G. (登録日: 2001-04-22, 公開日: 2001-05-02, 最終更新日: 2023-08-16)

主引用文献

Farazi, T.A.,Waksman, G.,Gordon, J.I.
Structures of Saccharomyces cerevisiae N-myristoyltransferase with bound myristoylCoA and peptide provide insights about substrate recognition and catalysis.
Biochemistry, 40:6335-6343, 2001

PubMed Abstract: MyristoylCoA:protein N-myristoyltransferase (Nmt) attaches myristate to the N-terminal Gly residue of proteins involved in a variety of signal transduction cascades, and other critical cellular functions. To gain insight about the structural basis of substrate recognition and catalysis, we determined the structures of a binary complex of Saccharomyces cerevisiae Nmt1p with myristoylCoA to 2.2 A resolution and of a ternary complex of Nmt1p with a nonhydrolyzable myristoylCoA analogue [S-(2-oxo)pentadecylCoA] and an octapeptide substrate (GLYASKLA) to 2.5 A resolution. The binary complex reveals how myristoylCoA alters the conformation of the enzyme to promote binding of both myristoylCoA and peptide and identifies the backbone amides of F170 and L171 as an oxyanion hole which polarizes the reactive thioester carbonyl. The ternary complex structure reveals details of the enzyme's peptide binding specificity and illuminates its mechanism of acyl transfer. The N-terminal Gly ammonium is positioned in close proximity to the C-terminal carboxylate of the protein, where it is poised to undergo the required deprotonation to an amine. In this conformation, the nucleophile is 6.3 A away from the thioester carbonyl. A catalytic mechanism is proposed whereby, once deprotonation is initiated, the N-terminal Gly amine can approximate the thioester carbonyl by rotating along Psi. This motion is facilitated by a H-bond network and leads to reaction between the glycine nitrogen nucleophile and the carbonyl. Loss of CoA from the tetrahedral intermediate may be facilitated by intramolecular H-bonding of the sulfur to the adenylamine of CoA. This affords a compact leaving group and lends a role for the observed bends in the CoA structure. The absolute requirement for Gly at the N-terminus of substrates is explained by the requirement for flexible rotation of its amine.

PubMed: 11371195
DOI: 10.1021/bi0101401

実験手法

X-RAY DIFFRACTION (2.5 Å)