Superficial structures involved in the interaction Lactobacillus kefir - Escherichia coli

GERBINO, O; CARASI, P; MOBILI, P; SERRADELL, M; DE URRAZA, P; ARLUISON, V; GÓMEZ-ZAVAGLIA, A

Salta

Congreso; III Latin American Protein Society Meeting; 2010

Latin American 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. Several lactobacilli strains bearing an S-layer structure play an essential role as probiotics for humans and animals. In this work, strategies to analyze the interaction of S-layers with the outer membranes (OM) of Gram(-) will be the aim of understanding the molecular mechanisms involved in certain probiotic properties. S-layer proteins were extracted from bacteria using 5M LiCl. 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.