Architecture of the pore forming toxin sticholysin I in membranes

Autor(en): Hervis, Yadira P.
Valle, Aisel
Dunkel, Sabrina
Klare, Johann P.
Canet, Liem
Lanio, Maria E.
Alvarez, Carlos
Pazos, Isabel F.
Steinhoff, Heinz-J
Stichwörter: ACTINOPORINS; Biochemistry & Molecular Biology; Biophysics; Cell Biology; EPR spectroscopy; EQUINATOXIN-II; HELIX-G; NITROXIDE MOTION; OLIGOMERIZATION; Pore-forming toxins; SEA-ANEMONE; SIDE-CHAINS; Site-directed spin labeling; SPIN-LABELED PROTEINS; Sticholysin; STRUCTURAL DETERMINANTS; T4 LYSOZYME
Erscheinungsdatum: 2019
Herausgeber: ACADEMIC PRESS INC ELSEVIER SCIENCE
Journal: JOURNAL OF STRUCTURAL BIOLOGY
Volumen: 208
Ausgabe: 1
Startseite: 30
Seitenende: 42
Zusammenfassung: 
Sticholysin I (StI) is a toxin produced by the sea anemone Stichodactyla helianthus and belonging to the actinoporins family. Upon binding to sphingomyelin-containing membranes StI forms oligomeric pores, thereby leading to cell death. According to recent controversial experimental evidences, the pore architecture of actinoporins is a debated topic. Here, we investigated the StI topology in membranes by site-directed spin labeling and electron paramagnetic resonance spectroscopy. The results reveal that StI in membrane exhibits an oligomeric architecture with heterogeneous stoichiometry of predominantly eight or nine protomers, according to the available structural models. The StI topology resembles the conic pore structure reported for the actinoporin fragaceatoxin C. Our data show that StI coexists in two membrane-associated conformations, with the N-terminal segment either attached to the protein core or inserted in the membrane forming the pore. This finding suggests a `pre-pore' to `pore' transition determined by a conformational change that detaches the N-terminal segment.
ISSN: 10478477
DOI: 10.1016/j.jsb.2019.07.008

Show full item record

Page view(s)

1
Last Week
0
Last month
0
checked on Mar 3, 2024

Google ScholarTM

Check

Altmetric