"Superficial Structures Involved in the Interaction Lactobacillus kefir - Escherichia coli"

E. GERBINO, P. CARASI, P. MOBILI, M. SERRADELL, P. DE URRAZA, V. ARLUISON AND A. GÓMEZ ZAVAGLIA

Salta

Congreso; Latin American Protein Society Meeting. Salta. Argentina. 13-16/10/2010.; 2010

Latinoamerican Protein Society

The S-layer is a crystalline bidimensional array of (glyco)proteic subunits, linked non-covalently to each other underlying cell-wall of some bacteria [1]. Several lactobacilli strains bearing an S-layer structure play an essential role as probiotics for humans and animals [2]. In this work, strategies to analyze the interaction of S-layers with the outer membranes (OM) of Gram(-) will be presented with the aim of understanding the molecular mechanisms involved in certain probiotic properties. S-layer proteins were extracted from bacteria using LiCl 5M. FTIR spectroscopy was used to study the secondary structure of S-layer proteins from lactobacilli. The differences in the secondary structures of the investigated S-layers proteins were correlated with the investigated probiotic properties. The assembly of these various macromolecular structures and strategies adopted to analyze the interaction of E. coli OM with L. kefir S-layer will be presented herein, with the aim to understand the molecular mechanisms involved in the interaction.