Self-Assembly of <i>Escherichia coli</i> Phage Shock Protein A

Abstract

The Phage shock protein (Psp) response is an extracytoplasmic stress response. The central component of this system is PspA, a protein that mediates the physiological response to membrane stress. PspA is also involved in regulating its own transcription and that of the psp operon, forming a positive feedback loop. PspA has been previously shown to oligomerise into higher-order species, including a 36-meric species with ring-like structure. In this study, we demonstrate that the ring-like PspA structures further self-assemble into rod-shaped complexes. These rod-like structures may play a scaffolding role in the maintenance of membrane integrity during phage shock protein response.

VIPP2 interacts with VIPP1 and HSP22E/F at chloroplast membranes and modulates a retrograde signal for HSP22E/F gene expression

“…In both PspA and VIPP1, the N‐terminal 24 amino acids form an amphipathic α‐helix (AHa) that is required for membrane binding and the formation of larger oligomers (Gao, Wang, Zhang, & Liu, ; Jovanovic et al, ; McDonald, Jovanovic, Ces, & Buck, ; McDonald, Jovanovic, Wallace, Ces, & Buck, ; Otters et al, ). In vitro, both proteins form higher order oligomers of >1 MDa that give rise to rings and rods (Aseeva et al, ; Fuhrmann, Bultema, et al, ; Hankamer, Elderkin, Buck, & Nield, ; Liu et al, ; Male, Oyston, & Tavassoli, ; Saur et al, ). Rods formed by recombinant VIPP1 from Chlamydomonas can engulf liposomes containing physiological amounts of phosphatidylinositol phosphate (Theis, Gupta, et al, ).…”

Understanding properties of the master effector of phage shock operon in Mycobacterium tuberculosis via bioinformatics approach

“…PspA is the central constituent of bacterial stress response machinery, encoded by phage shock operon (Huvet et al, 2010). PspA, regulates not only it's own transcription but that of the whole operon as well (Elderkin et al, 2005;Male et al, 2014).…”

“…PspA is inferred to be a dual-function protein (Guegwen et al, 2009;Jovanovic et al, 2014) and localized amid cytoplasmic and inner membrane interface of the bacterium (Engl et al, 2009). It is responsible for maintaining the cell membrane integrity along with restoration of the proton motive force (Male et al, 2014;Engl et al, 2009;Wan et al, 2015).…”

“…Despite low sequence conservation, the structure is however, well conserved due to the underlying fact that the protein folds remain conserved in similar function proteins. PspA structure in Escherichia coli is known to self-assemble into ring (Standar et al, 2008) or striated and indented rod-shaped complexes (Male et al, 2014) based on electron microscopy and helical rods based on X-ray crystallography analysis (Osadnik et al, 2015). PspA homologue LiaH in Bacillus subtilis (Wolf et al, 2008) and…”

“…PspA is also rod shaped and it is implied that these rod-like structures could form a support framework and aid in the maintenance of membrane integrity during phage shock response (Male et al, 2014).…”