Movement of a loop in domain 3 of aerolysin is required for channel formation

Biochemistry
J RossjohnJ T Buckley

Abstract

Aerolysin is a channel-forming toxin that must oligomerize in order to become insertion-competent. Modeling based on the crystal structure of the proaerolysin dimer and electron microscopic images of the oligomer indicated that a loop in domain 3 must move away from the beta-sheet that forms the main body of the protein before oligomerization can proceed. In order to determine if movement actually occurs, strategically located amino acids in the loop and in the sheet were replaced with cysteines by site-directed mutagenesis. A double mutant was produced in which the new cysteines, at position 253 on the loop and position 300 in the sheet, were close enough together to allow formation of a disulfide bridge. The double mutant was unable to oligomerize, and it was completely inactive, showing not only that the bridge had formed but also that movement of the loop was essential for formation of the oligomer. The existence of the bridge was confirmed by X-ray crystallography. The reduced form of the protein and the single mutants T253C and A300C were as active as wild type, indicating that the amino acid replacements themselves had no functional consequences. Labeling studies using an environment-sensitive fluorescent sulfhydryl-reac...Continue Reading

References

Apr 20, 1990·Journal of Molecular Biology·A D TuckerJ T Buckley

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Citations

Nov 25, 2004·Progress in Biophysics and Molecular Biology·Michael W Parker, Susanne C Feil
Feb 6, 2004·Toxicon : Official Journal of the International Society on Toxinology·Karina N LaohachaiJoseph I Kourie
Jan 23, 1999·Current Opinion in Structural Biology·D B Lacy, R C Stevens
Sep 2, 2009·The Journal of Biological Chemistry·Teal M Pelish, Mark S McClain
Dec 9, 2010·Acta Crystallographica. Section F, Structural Biology and Crystallization Communications·Lucile PernotF Gisou van der Goot
Jul 27, 1999·Molecular Microbiology·D H NguyenJ E Hildreth
Dec 24, 2005·Proteins·Karine BastardMartin Zacharias
Oct 12, 2004·Biochemical and Biophysical Research Communications·Dong-Jun ShinYeongjin Hong
Feb 27, 2008·Biochimica Et Biophysica Acta·Ioan IacovacheLucile Pernot
Aug 26, 2003·Brazilian Journal of Medical and Biological Research = Revista Brasileira De Pesquisas Médicas E Biológicas·E F SchwartzL C Salomão
Apr 13, 2005·The Journal of Biological Chemistry·Daniel SherEliahu Zlotkin
Jan 21, 2006·The EMBO Journal·Ioan IacovacheF Gisou van der Goot
Dec 14, 1999·The Journal of Biological Chemistry·C LesieurF G van der Goot
Jan 13, 2004·The Journal of Biological Chemistry·Jody A MeltonRodney K Tweten
Apr 30, 2003·Protein Science : a Publication of the Protein Society·Toshimitsu Kawate, Eric Gouaux

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