A Soluble Metabolon Synthesizes the Isoprenoid Lipid Ubiquinone.
SCP2
bioenergetics
hydroxylation
lipid biosynthesis
membrane
metabolic pathway
metabolon
multiprotein complex
respiration
ubiquinone
Journal
Cell chemical biology
ISSN: 2451-9448
Titre abrégé: Cell Chem Biol
Pays: United States
ID NLM: 101676030
Informations de publication
Date de publication:
18 04 2019
18 04 2019
Historique:
received:
16
10
2018
revised:
14
11
2018
accepted:
29
11
2018
pubmed:
29
1
2019
medline:
28
1
2020
entrez:
29
1
2019
Statut:
ppublish
Résumé
Ubiquinone (UQ) is a polyprenylated lipid that is conserved from bacteria to humans and is crucial to cellular respiration. How the cell orchestrates the efficient synthesis of UQ, which involves the modification of extremely hydrophobic substrates by multiple sequential enzymes, remains an unresolved issue. Here, we demonstrate that seven Ubi proteins form the Ubi complex, a stable metabolon that catalyzes the last six reactions of the UQ biosynthetic pathway in Escherichia coli. The SCP2 domain of UbiJ forms an extended hydrophobic cavity that binds UQ intermediates inside the 1-MDa Ubi complex. We purify the Ubi complex from cytoplasmic extracts and demonstrate that UQ biosynthesis occurs in this fraction, challenging the current thinking of a membrane-associated biosynthetic process. Collectively, our results document a rare case of stable metabolon and highlight how the supramolecular organization of soluble enzymes allows the modification of hydrophobic substrates in a hydrophilic environment.
Identifiants
pubmed: 30686758
pii: S2451-9456(18)30439-2
doi: 10.1016/j.chembiol.2018.12.001
pii:
doi:
Substances chimiques
Carrier Proteins
0
Escherichia coli Proteins
0
Terpenes
0
UbiJ protein, E coli
0
Ubiquinone
1339-63-5
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
482-492.e7Commentaires et corrections
Type : CommentIn
Informations de copyright
Copyright © 2018 Elsevier Ltd. All rights reserved.