8EAX

Octameric prenyltransferase domain of fusicoccadiene Synthase with C2 symmetry sans transiently associating cyclase domains

8EAX の概要

• エントリーDOI: 10.2210/pdb8eax/pdb
• EMDBエントリー: 27989
• 分子名称: Fusicoccadiene synthase (1 entity in total)
• 機能のキーワード: terpene synthase, prenyltransferase, transferase
• 由来する生物種: Diaporthe amygdali
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 671423.82

構造登録者

Faylo, J.L.,van Eeuwen, T.,Christianson, D.W. (登録日: 2022-08-29, 公開日: 2022-11-02, 最終更新日: 2025-05-21)

主引用文献

Faylo, J.L.,van Eeuwen, T.,Gupta, K.,Murakami, K.,Christianson, D.W.
Transient Prenyltransferase-Cyclase Association in Fusicoccadiene Synthase, an Assembly-Line Terpene Synthase.
Biochemistry, 61:2417-2430, 2022

PubMed Abstract: Fusicoccadiene synthase from the fungus (PaFS) is an assembly-line terpene synthase that catalyzes the first two steps in the biosynthesis of Fusiccocin A, a diterpene glycoside. The C-terminal prenyltransferase domain of PaFS catalyzes the condensation of one molecule of C dimethylallyl diphosphate and three molecules of C isopentenyl diphosphate to form C geranylgeranyl diphosphate, which then transits to the cyclase domain for cyclization to form fusicoccadiene. Previous structural studies of PaFS using electron microscopy (EM) revealed a central octameric prenyltransferase core with eight cyclase domains tethered in random distal positions through flexible 70-residue linkers. However, proximal prenyltransferase-cyclase configurations could be captured by covalent cross-linking and observed by cryo-EM and mass spectrometry. Here, we use cryo-EM to show that proximally configured prenyltransferase-cyclase complexes are observable even in the absence of covalent cross-linking; moreover, such complexes can involve multiple cyclase domains. A conserved basic patch on the prenyltransferase domain comprises the primary touchpoint with the cyclase domain. These results support a model for transient prenyltransferase-cyclase association in which the cyclase domains of PaFS are in facile equilibrium between proximal associated and random distal positions relative to the central prenyltransferase octamer. The results of biophysical measurements using small-angle X-ray scattering, analytical ultracentrifugation, dynamic light scattering, and size-exclusion chromatography in-line with multi-angle light scattering are consistent with this model. This model accordingly provides a framework for understanding substrate transit between the prenyltransferase and cyclase domains as well as the cooperativity observed for geranylgeranyl diphosphate cyclization.

PubMed: 36227241
DOI: 10.1021/acs.biochem.2c00509

実験手法

ELECTRON MICROSCOPY (3.73 Å)