Interakcije ekvinatoksina II iz morske vetrnice Actinia equina z lipidnimi membranami : doktorska disertacija = Interactions of equinatoxin II from sea anemone Actinia equina with lipid membranes : dissertation thesis
Barlič, Ariana
Equinatoxin II (EqtII) is a basic protein from a sea anemone (Actinia equina L.), composed of 179 amino acids. It belongs to a large group of cytolytic toxins, capable of forming pores in biological ...membranes and artificial lipid bilayers. Despite the fact that molecule is relatively well characterized, details of its insertion into membrane and pore-formation are not known yet. To get more insight into these interactions, EqtIIćs tryptophan mutants had been produced and used in studies with model membrane systems. For the first time, atomic force microscopy was employed to observe oligomeric assemblies and ring-shaped structures of EqtII on supported planar lipid bilayers. Intrinsic fluorescence measurements of native EqtII, which contains five Trp residues, and EqtII mutants Trp45, Trp116.117 and Trp149 (number indicates preserved tryptophan residueč all others were substituted by Phe) showed transfer of residues Trp116 and Trp117 into the lipid bilayer upon membrane binding. Since residue Trp112 is located in immediate vicinity, we propose transfer of the whole hydrophobic cluster (residues 112-117) into the membrane. By the means of fluorescence resonance energy transfer we estimated location of residues Trp116 and Trp117 within the membrane. They are located approximately 2,2 nm from the center of the hydrophobic core, in lipidžwater interface, thus resembling other membrane active proteins. Further characterization of the mutant Trp116.117 included binding studies to SUVs, measured by fluorescence anisotropy. We found out that the mutant binds almost10x stronger than the native toxin. Accordina to ANS fluorescence measurements. one reason for this could be in a more ĆrelaxedĆ conformation ofthe molecule, although secondary structural elements are preserved. The mutant also showed a higher binding affinity for homogenous lipid surfaces. (Abstract truncated at 2000 characters)
Type of material - dissertation
; adult, serious
Publication and manufacture - Ljubljana : [A. Barlič], 2000
National Institute of Biology and BF, Department of Biology, Ljubljana
BF oddelek za biologijo dr 577.2 BARLIČ A. Interakcije IN: 0022251
available - reading room
Shelf entry
Adding material to shelf was successful.
Adding material to shelf failed.
It was not necessary to add the material to the shelf.
Bibliographic material was successfully added on shelf.
Adding bibliographical material on shelf was not successful.
Material is already on the shelf.
Permalink
URL:
Impact factor
Access to the JCR database is permitted only to users from Slovenia. Your current IP address is not on the list of IP addresses with access permission, and authentication with the relevant AAI accout is required.
Year
Impact factor
Edition
Category
Classification
JCR
SNIP
JCR
SNIP
JCR
SNIP
JCR
SNIP
Select the library membership card:
DRS,
in which the journal is indexed
Database name
Field
Year
Links to authors' personal bibliographies
Links to information on researchers in the SICRIS system
Subject headings in COBISS General List of Subject Headings
Select pickup location
The material from the parent unit is free. If the material is delivered to the pickup location from another unit, the library may charge you for this service.
