Electrostatic Study of the Interaction betw een 33-mer Octamer and Biological Membranes

MARÍA JULIA AMUNDARAIN; FERNANDO ZAMARREÑO; JUAN FRANCISCO VISO; VERONICA DODERO; MARCELO DANIEL COSTABEL

Sierra de la Ventana

Congreso; XLIII Reunión Anual de la Sociedad Argentina de Biofísica; 2014

Universidad Nacional del Sur

33-mer is an immunogenic peptide derived from the digestion of the protein α2-gliadin and is proposed to be the trigger of the inflammation process in Celiac disease. In vitro experiments have shown that it presents a supramolecular behavior that could be related to the development of the disease. In this work we applied biophysical and computational techniques to evaluate the interaction between an oligomer of 33-mer peptide and different biological membranes. Firstly, we obtained the octamer from a molecular dynamics simulation of ten 33-mer monomers in water. We saw how eight of them interacted, came close to each other and formed a primitive oligomer. Afterwards we carried on with the simulation of the octamer for 50 ns, obtaining a stable structure of interesting size. The MD simulations were performed with GROMACS package. The interaction with the membrane was assessed through calculations of electrostatic energy of interaction, for different positions and relative orientations, by making use of the software APBS (Adaptative Poisson-Boltzmann Solver).