9RY8

Crystal structure of PfaB from Shewanella baltica strain 6-42

9RY8 の概要

• エントリーDOI: 10.2210/pdb9ry8/pdb
• 分子名称: PfaBs (1 entity in total)
• 機能のキーワード: acyltransferase, polyketide synthase, fatty acid synthase, polyunsaturated fatty acid, dha, epa., lipid binding protein
• 由来する生物種: Shewanella baltica
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 78733.09

構造登録者

Lofeudo, N.,Martin, A.,Jacome, M.,Wan, X.,Lucas, M.,Moncalian, G. (登録日: 2025-07-14, 公開日: 2026-02-25)

主引用文献

Lofeudo, N.,Martin, A.,Jacome, M.,Wan, X.,Lucas, M.,Moncalian, G.
Prokaryotic PfaB is a terminal acyltransferase that determines the final PUFA product.
Protein Sci., 35:e70497-e70497, 2026

PubMed Abstract: Omega-3 polyunsaturated fatty acids (PUFAs) are essential for human health due to their numerous beneficial biological properties. These compounds are synthesized in marine bacteria and eukaryotic microalgae by PUFA megasynthases (Pfas), which are evolutionarily related to fatty acid synthases (FAS) and polyketide synthases (PKS). In FAS, PKS, and PUFA synthases, the acyltransferase (AT) domain plays a critical role in condensation reactions by loading starter or extender units into the acyl carrier protein (ACP) domain. PfaB, a component of PUFA megasynthases, harbors a pseudo-ketosynthase (KS') domain and an AT domain. In this study, we show that PfaB determines the final PUFA product, as demonstrated by in vivo assays in Escherichia coli using the DHA-producing Moritella marina and the EPA-producing Shewanella baltica. In vitro biochemical assays confirm that PfaB exhibits acyltransferase activity, with distinct substrate specificity from the AT domain of PfaA. Finally, we report the crystal structure of PfaB from S. baltica, representing the first structurally resolved AT domain within a PUFA megasynthase. Molecular docking analyses suggest that specific residues may contribute to differences in substrate recognition and specificity. Together, these findings show that PfaB acts as the terminal acyltransferase, providing new insights into its functional role in PUFA biosynthesis, and advancing our understanding of its mechanism and ligand interactions.

PubMed: 41676921
DOI: 10.1002/pro.70497

実験手法

X-RAY DIFFRACTION (2.9 Å)