Membrane interactions and surface hydrophobicity of Bacillus thuringiensis δ‐endotoxin CryIC

FEBS Letters

Surewicz, Witold K.¹  Pusztai-Carey, Marianne¹  Cournoyer, Micheline¹  Butko, Peter¹ 

[1] Institute for Biological Sciences, National Research Council, Ottawa, Ontario K1A 0R6, Canada

关键词: δ-Endotoxin;    Fluorescence probes;    Membrane permeabilization;    Surface hydrophobicity;    Bacillus thuringiensis;    bis-ANS;    1;    1'-bi(4-anilino)naphthalene-5;    5'-disulfonic acid;    CAPS;    3-(cyclohexylamino)-1-propanesulfonic acid;    diSC2(5);    3;    3'-diethylthiadicarbocyanine iodide;    HEPES;    N-(2-hydroxyethyl)-piperazine-N'-(2-ethanesulfonic acid);    LUV;    large unilamellar vesicles;    PC;    l-α-phosphatidylcholine;    PG;    1-palmitoyl-2-oleoyl-ssn-glycero-3-[phospho-rac-(1-glycerol)];   

DOI  :  10.1016/0014-5793(94)80178-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The interaction between Bacillus thuringiensis insecticidal 5-endotoxin CryIC and phospholipid vesicles was studied by fluorescence spectroscopy. The toxin dissipates the diffusion potential across vesicular membranes, presumably by creating ion permeable channels or pores. This effect is pH-dependent and strongly increases under acidic conditions. The enhanced membrane-perturbing activity of CryIC at low pH correlates with the increased surface hydrophobicity of the toxin molecule. The membrane permeabilizing effect of the toxin is further increased by the presence of acidic phospholipids. These findings are discussed in relation to the mode of insecticidal action of the toxin.

【 授权许可】

Unknown