CONTEXT

The study of ligand binding to membrane proteins (MPs) requires that the proteins be immobilised on a substrate. Current immobilisation protocols frequently result in non-specific adsorption or MP denaturation. No method currently exists to immobilise MPs without denaturation via a simple and general protocol.

TECHNICAL DESCRIPTION

The present invention overcomes this limitation thanks to synthetic molecules called « amphipols » (APols), which can mediate the immobilisation of functional MPs onto virtually any kind of supports. APols are amphipatic polymers designed to bind spontaneously and tenaciously to the transmembrane surface of MPs, while stabilizing them biochemically. APols can be made to carry any desired function e.g. one that will drive immobilization by associating to a complementary function presented by the support. The claims include products consisting of a support and at least one MP fixed on its surface through an APol. They also include kits comprising the support and the APol for the preparation of such devices, using MPs produced in-house by the customer.

BENEFITS

The key advantages of this invention are:

=> the universality of this approach: functionalised APols can be used as universal adapters to associate any MP to virtually any kind of support while stabilising its native state;

=> it is easy to implement, extremely mild, technologically very light (it requires minimal quantities of reagents), remarkably versatile (a large panel of observation techniques can be used to examine MP/ligand interactions due to the vast variety of tags or chemical functions mediating the attachment on the support), and it does not call for any genetic or chemical modification of the target protein;

=> it is suitable for multiplexing and high-throughput screening.

INDUSTRIAL APPLICATIONS

This invention opens the way to a wide range of applications related to the study of protein/ligand interaction (protein chips, search for natural biological partners of MPs, immunodetection, drug screening, diagnostics, creation of biosensors…), but can also include the design of biomaterials or bioreactors.

DEVELOPMENT STAGE

The generality and versatility of this approach has been demonstrated by using 5 different target proteins, 2 types of supports (chips and beads), 2 types of ligands (antibodies and a snake toxin), and 2 detection methods (surface plasmon resonance and fluorescence microscopy)1.

Reference: Charvolin et al., 2009, PNAS, 106:405-410