Characterisation of the heptameric pore‐forming complex of the Aeromonas toxin aerolysin using MALDI‐TOF mass spectrometry

FEBS Letters

Moniatte, M.⁴  Pattus, F.³  van der Goot, F.G.²  Buckley, J.T.¹  van Dorsselaer, A.⁴ 

[1] Department of Biochemistry and Microbiology, University of Victoria, Box 3055, Victoria, B.C., Canada V8W 3P6;Département de Biochimie, Université de Genève, 30 quai E. Ansermet, 1211 Genève, Switzerland;Département Récepteurs et Protéines Membranaires, UPR 9050 CNRS, Rue Sébastien Brant, 67400 Illkirch, France;Laboratoire de Spectrométrie de Masse Bio-Organique associé au CNRS, Université Louis Pasteur, 1, rue B. Pascal, 67008 Strasbourg, France

关键词: Matrix-assisted laser desorption/ionization;    Mass spectrometry;    Aerolysin;    Non-covalent interaction;    Oligomerization;    Pore-forming toxin;    MALDI-TOF;    matrix-assisted laser desorption/ionization;    ESMS;    electrospray mass spectrometry;   

DOI  :  10.1016/0014-5793(96)00328-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Aerolysin, a virulence factor secreted by Aeromonas hydrophila, is representative of a group of β-sheet toxins that must form stable homooligomers in order to be able to insert into biological membranes and generate channels. Electron microscopy and image analysis of two-dimensional membrane crystals had previously revealed a structure with 7-fold symmetry et al. (1992) EMBO J. 11, 2457–2463]. However, this unusual et al. (1992) EMBO J. 11, 2457–2463]. However, this unusual molecularity of the channel remained to be confirmed by an independent method since low-resolution electron crystallography had led to artefactual data for other pore-forming toxins. In this study, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was used to measure the mass of the aerolysin oligomer preparation. A mass of 333 850 Da was measured, fitting very well with a heptameric complex (expected mass: 332 300 Da). These results confirm the earlier evidence that the aerolysin oligomer is a heptamer and also show that MALDI-TOF mass spectrometry could be a valuable tool to study non-covalent association of proteins.

【 授权许可】

Unknown