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Symmetry requirements for effective blocking of pore-forming toxins: comparative study with alpha-, beta-, and gamma-cyclodextrin derivatives.

ABSTRACT: We compared the abilities of structurally related cationic cyclodextrins to inhibit Bacillus anthracis lethal toxin and Staphylococcus aureus ?-hemolysin. We found that both ?- and ?-cyclodextrin derivatives effectively inhibited anthrax toxin action by blocking the transmembrane oligomeric pores formed by the protective antigen (PA) subunit of the toxin, whereas ?-cyclodextrins were ineffective. In contrast, ?-hemolysin was selectively blocked only by ?-cyclodextrin derivatives, demonstrating that both symmetry and size of the inhibitor and the pore are important.

SUBMITTER: Yannakopoulou K

PROVIDER: S-EPMC3122465 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Symmetry requirements for effective blocking of pore-forming toxins: comparative study with alpha-, beta-, and gamma-cyclodextrin derivatives.

Yannakopoulou Konstantina K Jicsinszky Laszlo L Aggelidou Crysie C Mourtzis Nikolaos N Robinson Tanisha M TM Yohannes Adiamseged A Nestorovich Ekaterina M EM Bezrukov Sergey M SM Karginov Vladimir A VA

Antimicrobial agents and chemotherapy 20110509 7

We compared the abilities of structurally related cationic cyclodextrins to inhibit Bacillus anthracis lethal toxin and Staphylococcus aureus α-hemolysin. We found that both β- and γ-cyclodextrin derivatives effectively inhibited anthrax toxin action by blocking the transmembrane oligomeric pores formed by the protective antigen (PA) subunit of the toxin, whereas α-cyclodextrins were ineffective. In contrast, α-hemolysin was selectively blocked only by β-cyclodextrin derivatives, demonstrating t ...[more]

PMID: 21555769

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