Functional microdomains in bacterial membranes

TLDR

Eukaryotic membranes contain lipid‑raft microdomains rich in signaling and transport proteins, and this organization may be a widespread feature of cellular membranes. Bacterial membranes possess microdomains functionally analogous to eukaryotic lipid rafts, containing Flotillin‑1 homologs and signaling/transport proteins, and disrupting raft formation with zaragozic acid reduces biofilm formation and protein secretion without affecting cell viability.

Abstract

The membranes of eukaryotic cells harbor microdomains known as lipid rafts that contain a variety of signaling and transport proteins. Here we show that bacterial membranes contain microdomains functionally similar to those of eukaryotic cells. These membrane microdomains from diverse bacteria harbor homologs of Flotillin-1, a eukaryotic protein found exclusively in lipid rafts, along with proteins involved in signaling and transport. Inhibition of lipid raft formation through the action of zaragozic acid--a known inhibitor of squalene synthases--impaired biofilm formation and protein secretion but not cell viability. The orchestration of physiological processes in microdomains may be a more widespread feature of membranes than previously appreciated.