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Melittin as model system for probing interactions between proteins and cyclodextrins.

Mazdak Khajehpour·Thomas Troxler·Vikas Nanda·Jane M Vanderkooi
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Abstract

Cylcodextrin sugars are cyclic sugars that have a hydrophilic exterior and a hydrophobic center. This enables cyclodextrins to solubilize hydrophobic molecules in aqueous media. Cyclodextrins may inhibit aggregation by intercalating surface aromatic residues and competing with interprotein aromatic clusters (pi-pi interactions). In order to investigate this concept, the interaction of hydroxypropyl-beta-cyclodextrin (HPBCD) with melittin is studied with steady-state and time-resolved fluorescence, fluorescence polarization, circular dichroism, and IR spectroscopy. HPBCD inhibits the aggregation of melittin. This inhibition and the spectroscopic results are consistent with the lone aromatic tryptophan of the peptide being intercalated within HPBCD.

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2-Hydroxypropyl-beta-cyclodextrinAnisotropyCircular DichroismCold TemperatureCyclodextrinsFluorescence PolarizationHydrogen BondingHydrophobic and Hydrophilic InteractionsMelittenModels, MolecularProtein BindingSaltsSpectrophotometry, InfraredTime FactorsTryptophanbeta-CyclodextrinsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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Mazdak Khajehpour, Thomas Troxler, Vikas Nanda, Jane M Vanderkooi. 2004-05-01. Melittin as model system for probing interactions between proteins and cyclodextrins.. https://doi.org/10.1002/prot.20036

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