Flotillin-mediated membrane fluidity controls peptidoglycan synthesis and MreB movement

Abstract

The bacterial plasma membrane is an important cellular compartment. In recent years it has become obvious that protein complexes and lipids are not uniformly distributed within membranes. Current hypotheses suggest that flotillin proteins are required for the formation of complexes of membrane proteins including cell-wall synthetic proteins. We show here that bacterial flotillins are important factors for membrane fluidity homeostasis. Loss of flotillins leads to a decrease in membrane fluidity that in turn leads to alterations in MreB dynamics and, as a consequence, in peptidoglycan synthesis. These alterations are reverted when membrane fluidity is restored by a chemical fluidizer. In vitro, the addition of a flotillin increases membrane fluidity of liposomes. Our data support a model in which flotillins are required for direct control of membrane fluidity rather than for the formation of protein complexes via direct protein-protein interactions.

Membrane-partitioned cell wall synthesis in mycobacteria

“…Next, we wanted to understand the significance of membrane architecture for cell wall synthesis. We perturbed the membrane with benzyl alcohol, a compound that preferentially inserts into disordered membrane regions in vitro ( Muddana et al, 2012 ) and has been used to fluidize membranes from mammalian and bacterial cells ( Friedlander et al, 1987 ; Ingram, 1976 ; Konopásek et al, 2000 ; Nagy et al, 2007 ; Strahl et al, 2014 ; Zielińska et al, 2020 ). In B. subtilis , benzyl alcohol disrupts RIFs ( Müller et al, 2016 ).…”

The PASTA domains of Bacillus subtilis PBP2B strengthen the interaction of PBP2B with DivIB

“…2 , Table S2). In other work, we observed that some phenotypes associated with peptidoglycan synthesis defects at the septum are not observed when cells are grown on minimal medium [ 30 ]. Therefore, we also analysed the effect of the deletion of PASTA domains in cells grown in a defined minimal medium (SM medium).…”

Alteration of Membrane Fluidity or Phospholipid Composition Perturbs Rotation of MreB Complexes in Escherichia coli

“…Thus, there is a smaller effect on the formation of the Rod complex, but the impact on complex dynamics may be significant in aPLs cells. While this manuscript was under review, it was reported that membrane fluidity controls MreB motion in Bacillus subtilis (Zielińska et al, 2020). Thus, membrane fluidity controls the motion of the Rod complex in both gram-positive and gram-negative bacteria.…”