Spatial organization of bacterial sphingolipid synthesis enzymes

Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved..

Sphingolipids are produced by nearly all eukaryotes where they play significant roles in cellular processes such as cell growth, division, programmed cell death, angiogenesis, and inflammation. While it was previously believed that sphingolipids were quite rare among bacteria, bioinformatic analysis of the recently identified bacterial sphingolipid synthesis genes suggests that these lipids are likely to be produced by a wide range of microbial species. The sphingolipid synthesis pathway consists of three critical enzymes. Serine palmitoyltransferase catalyzes the condensation of serine with palmitoyl-CoA (or palmitoyl-acyl carrier protein), ceramide synthase adds the second acyl chain, and a reductase reduces the ketone present on the long-chain base. While there is general agreement regarding the identity of these bacterial enzymes, the precise mechanism and order of chemical reactions for microbial sphingolipid synthesis is more ambiguous. Two mechanisms have been proposed. First, the synthesis pathway may follow the well characterized eukaryotic pathway in which the long-chain base is reduced prior to the addition of the second acyl chain. Alternatively, our previous work suggests that addition of the second acyl chain precedes the reduction of the long-chain base. To distinguish between these two models, we investigated the subcellular localization of these three key enzymes. We found that serine palmitoyltransferase and ceramide synthase are localized to the cytoplasm whereas the ceramide reductase is in the periplasmic space. This is consistent with our previously proposed model wherein the second acyl chain is added in the cytoplasm prior to export to the periplasm where the lipid molecule is reduced.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - year:2024

Enthalten in:

The Journal of biological chemistry - (2024) vom: 06. Apr., Seite 107276

Sprache:

Englisch

Beteiligte Personen:

Uchendu, Chioma G [VerfasserIn]
Guan, Ziqiang [VerfasserIn]
Klein, Eric A [VerfasserIn]

Links:

Volltext

Themen:

Ceramide
Journal Article
Lipid metabolism
Microbiology
Sphingolipid
Subcellular localization

Anmerkungen:

Date Revised 08.04.2024

published: Print-Electronic

Citation Status Publisher

doi:

10.1016/j.jbc.2024.107276

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM370781589