Characterization of a membrane-active peptide from the Bordetella pertussis CyaA toxin.
Bordetella pertussis, the pathogenic bacteria responsible for whooping cough, secretes several virulence factors, among which is the adenylate cyclase toxin (CyaA) that plays a crucial role in the early stages of human respiratory tract colonization. CyaA invades target cells by translocating its catalytic domain directly across the plasma membrane and overproduces cAMP, leading to cell death. The molecular process leading to the translocation of the catalytic domain remains largely unknown. We have previously shown that the catalytic domain per se, AC384, encompassing residues 1-384 of CyaA, did not interact with lipid bilayer, whereas a longer polypeptide, AC489, spanning residues 1-489, binds to membranes and permeabilizes vesicles. Moreover, deletion of residues 375-485 within CyaA abrogated the translocation of the catalytic domain into target cells. Here, we further identified within this region a peptidic segment that exhibits membrane interaction properties. A synthetic peptide, P454, corresponding to this sequence (residues 454-485 of CyaA) was characterized by various biophysical approaches. We found that P454 (i) binds to membranes containing anionic lipids, (ii) adopts an α-helical structure oriented in plane with respect to the lipid bilayer, and (iii) permeabilizes vesicles. We propose that the region encompassing the helix 454-485 of CyaA may insert into target cell membrane and induce a local destabilization of the lipid bilayer, thus favoring the translocation of the catalytic domain across the plasma membrane.
From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France.
Orso
O
Subrini
From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France.
Ana-Cristina
AC
Sotomayor-Pérez
From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France.
Audrey
A
Hessel
From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France.
Johanna
J
Spiaczka-Karst
the Institut Pasteur, CNRS UMR 3528, Unité de Bio-Informatique Structurale, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France.
Edithe
E
Selwa
the Commissariat à l'Energie Atomique, Direction des Sciences de la Vie, Institut de Recherches en Technologies et Sciences pour le Vivant, Laboratoire de Chimie et Biologie des Métaux, CEA Grenoble, 17 Rue des Martyrs, 38054 Grenoble, France.
Nicolas
N
Sapay
the Institut Charles Gerhardt, UMR 5253 CNRS/ENSCM/UM2/UM1, Equipe "Matériaux Avancés pour la Catalyse et la Santé", UFR des Sciences Pharmaceutiques et Biologiques, 15 Avenue Charles Flahault-BP 14 491, 34093 Montpellier Cedex 05, France.
Rémi
R
Veneziano
the Institut Charles Gerhardt, UMR 5253 CNRS/ENSCM/UM2/UM1, Equipe "Matériaux Avancés pour la Catalyse et la Santé", UFR des Sciences Pharmaceutiques et Biologiques, 15 Avenue Charles Flahault-BP 14 491, 34093 Montpellier Cedex 05, France.
Jonathan
J
Pansieri
the Institut Charles Gerhardt, UMR 5253 CNRS/ENSCM/UM2/UM1, Equipe "Matériaux Avancés pour la Catalyse et la Santé", UFR des Sciences Pharmaceutiques et Biologiques, 15 Avenue Charles Flahault-BP 14 491, 34093 Montpellier Cedex 05, France; the Université de Nîmes, Rue Docteur Georges Salan, 30021 Nîmes, France.
Joel
J
Chopineau
From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France,. Electronic address: daniel.ladant@pasteur.fr.
Daniel
D
Ladant
From the Institut Pasteur, CNRS UMR 3528, Unité de Biochimie des Interactions Macromoléculaires, Département de Biologie Structurale et Chimie, 28 Rue du Dr. Roux, 75724 Paris Cedex 15, France,. Electronic address: alexandre.chenal@pasteur.fr.
Alexandre
A
Chenal
D037361:Adenylate Cyclase Toxin / Q000737:chemistry* / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001886:Bordetella pertussis / Q000737:chemistry* / Q000378:metabolism; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008051:Lipid Bilayers / Q000737:chemistry* / Q000378:metabolism; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D017433:Protein Structure, Secondary; D021381:Protein Transport
D037361:Adenylate Cyclase Toxin; D001426:Bacterial Proteins; D008051:Lipid Bilayers; D010455:Peptides
Adenylate Cyclase (Adenylyl Cyclase); Bacterial Toxins; Circular Dichroism (CD); Infrared Spectroscopy; Membrane; Molecular Dynamics; Peptide Conformation; Phospholipid Vesicle