Dr. Radwan Al Faouri

Dr. Radwan Al Faouri |Clyto Access

University of Arkansas, Fayetteville, USA

Speaker

Expertise:

Biography: He is working as a faculty at University of Arkansas which is located at Fayetteville in USA,

Presentation:

Title: Potential Use of Lysenin Channels in Drug Release from Liposomes

Abstract:

Lysenin is a 297 amino acid protein isolated from the coelomic fluid of the earthworm Eisenia foetida, which inserts,as a channel protein, large conductance pores (~3nm) into bilayer lipid membranes containing sphingomyelin. Controlling this ability would greatly enhance the potential to develop new means to deliver or release medication or clean-up toxic material in the body.  Lysenin channels show voltage induced gating and activity modulation by ionic strength and pH, suggesting that electrostatic interaction plays a major role in establishing their electrical activity.Based on the electrostatic representation of lysenin, we propose a dipole moment model that explains the voltage induced gating of lysenin and the ligand induced gating. Both of these gating mechanismscouldtrigger conformational changes in the structure of this protein that lead to block the pathway of lysenin channel. More importantly, we suggest that the movement of the C-Terminus of lysenin under any oriented external electrical influence (electric field or ions) is responsible for the gating of lysenin. In this line of inquiries, we hypothesize that multivalent cations may affect the conducting characteristics of lysenin channels by modulating the electrostatic interaction. The negative charge that lysenin has in its lumen suggests it as a possible binding siteand would interact electrostatically with multivalent cations resulting in a conductance response due to the charge of multivalent cations. In this work, we show that multivalent cations interact with the lysenin (ligand induced gating) and inhibited the macroscopic conductance of a population of lysenin channels in a concentration dependent manner.The higher sensitivity encountered towards low monovalent ions concentration suggests a competition between monovalent and multivalent cations on the binding site of lysenin. Revealing the characteristics of this binding site will be supportive in better understanding of the mechanism of ligand induced gating and voltage induced gating. These results will have a direct impact on drug delivery applications when using these pores (lysenin channels) in liposomes as drug carriers.

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Related Conferences :

World Summit on Nanotechnology and Nanomedicine Research