Preprint Article Version 1 This version is not peer-reviewed

Lysenin Toxin Insertion Mechanism is Calcium-Dependent

Version 1 : Received: 5 May 2020 / Approved: 7 May 2020 / Online: 7 May 2020 (10:23:54 CEST)

How to cite: Munguira, I.L. Lysenin Toxin Insertion Mechanism is Calcium-Dependent . Preprints 2020, 2020050119 (doi: 10.20944/preprints202005.0119.v1). Munguira, I.L. Lysenin Toxin Insertion Mechanism is Calcium-Dependent . Preprints 2020, 2020050119 (doi: 10.20944/preprints202005.0119.v1).

Abstract

Pore Forming Toxins (PFTs), formed mainly by virulence factors of bacteria, belongs to Pore Forming Protein (PFP) family. Secreted as soluble monomers, they bind specific targets in membranes where their oligomerization and insertion place. Lysenin, a member of the PFTs, forms and oligomer after sphingomyelin binding, the so-called prepore, which become inserted forming a pore after a conformational change triggered by a pH decrease. In crowded conditions, oligomers tends to stay in prepore form because the prepore-to-pore transition is sterically blocked. In this study, we investigate the effect of calcium ions in those crowded conditions, finding that calcium act as a trigger for lysenin insertion. We localize the residues responsible for calcium sensitivity in a small α-helix. Our results are not only one of the few complete structural descriptions of prepore-to-pore transitions but the very first that involves a calcium triggering mechanism. The presence of glutamic or aspartic acids in the insertion domains could be an indication that calcium may be a general trigger for PFTs and more generally PFP.

Subject Areas

pore-forming toxins; calcium; high-speed atomic force microscopy

Comments (0)

We encourage comments and feedback from a broad range of readers. See criteria for comments and our diversity statement.

Leave a public comment
Send a private comment to the author(s)
Views 0
Downloads 0
Comments 0
Metrics 0


×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.