%0 Journal Article
%T Protein Interactions Investigated by the Raman Spectroscopy for Biosensor Applications
%A R. P. Kengne-Momo
%A Ph. Daniel
%A F. Lagarde
%A Y. L. Jeyachandran
%A J. F. Pilard
%A M. J. Durand-Thouand
%A G. Thouand
%J International Journal of Spectroscopy
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/462901
%X Interaction and surface binding characteristics of staphylococcal protein A (SpA) and an anti-Escherichia coli immunoglobulin G (IgG) were studied using the Raman spectroscopy. The tyrosine amino acid residues present in the ¦Á-helix structure of SpA were found to be involved in interaction with IgG. In bulk interaction condition the native structure of proteins was almost preserved where interaction-related changes were observed in the overall secondary structure (¦Á-helix) of SpA. In the adsorbed state, the protein structure was largely modified, which allowed the identification of tyrosine amino acids involved in SpA and IgG interaction. This study constitutes a direct Raman spectroscopic investigation of SpA and IgG (receptor-antibody) interaction mechanism in the goal of a future biosensor application for detection of pathogenic microorganisms. 1. Introduction Creating protein-protein and protein-surface interactions is the primary step of biological processes in bioimplants, bio-fouling, immunoassays, and biosensors [1]. Therefore, in the past few years, a great deal for research has been focussed on the understanding of the fundamental structure and physicochemical properties involved in these interactions [2, 3], because the applications are strongly connected in the good knowledge of these mechanisms. Structure and orientation changes are often a part of proteins interaction due to various factors such as specific/nonspecific attachment, hydration/dehydration, steric hindrance, competitive adsorption/desorption processes, and experimental conditions [4, 5]. However it appears that the protein interactions and their resulting structural conformations are very complicated processes. Facing protein interaction complexity, various analytical tools have been developed to characterize the exhibited different phenomena, physico-chemical behaviors, and interaction structures [4, 6¨C8]. Among these tools, the vibrational spectroscopic techniques, such as Raman spectroscopy, are considered as extremely useful tools to chemically and structurally investigate all material compounds, of which protein analysis now constitute a possible and interesting field of applications, more particularly, to determine secondary conformations and interaction structures [9¨C11]. Actually the Raman scattering technique is a vibrational molecular spectroscopy which, derives from an inelastic light scattering process. With the Raman spectroscopy, a laser photon is scattered by a sample molecule and loses (or gains) energy during the process. The amount of energy lost is seen as a
%U http://www.hindawi.com/journals/ijs/2012/462901/