Molecular-scale biophysical approaches are a privileged link between the atomic-level structural descriptions and the spatiotemporal in situ studies, providing invaluable information about the energetics and dynamics of biological macromolecules and assemblies in a relatively short time-scale and in close-to-physiological conditions.

Created in 2002, the Centre of Biophysics of Macromolecules and their Interactions (PFBMI) aims to group state-of-the-art equipment, adapted to the needs of the research teams of the Pasteur Institute and its International Network, together with the corresponding technical and methodological know-how, thereby providing a scientific environment conducive to world-class research in the field of macromolecular science.

The following technologies are presently available:

1) Analytical ultracentrifugation: ProteomeLab XL I & Optima XL-A ultracentrifuges (Beckman-Coulter).

2) Circular dichroism: Aviv 215 spectropolarimeter (Aviv Biomedical), with fluorescence and titration accessories; CD6 spectropolarimeter (Jobin-Yvon) with a “stopped-flow” accessory (Bio-Logic).

3) Fluorescence spectroscopy: Quantamaster C60 fluorimeter (Photon Technology International), with a polarisation module; KinetAsyst SF61-DX2 “stopped flow” instrument (Hi-Tech Scientific), with a polarisation module.

4) Infrared spectroscopy: MB104 spectrometer (ABB Bomem), with a DuraSamplIR II attenuated total reflectance accessory (SensIR).

5) Light scattering: DynaPro MS800 dynamic light scattering instrument (Wyatt); TDA 302 light scattering-intrinsic viscosity-refractive index triple detector array (Viscotek), coupled to a GPCmax size exclusion chromatography system.

6) Microcalorimetry: VP-ITC & MCS-ITC isothermal titration calorimeters; VP-DSC differential scanning calorimeter, with a Pressure Perturbation Calorimetry accessory (PPC) (MicroCal).

7) Surface plasmon resonance: Biacore 2000 biosensor (Biacore).

People wishing to use the instruments of the PFBMI, or seeking expert advice related to these technologies, must send an e-mail to a centralized address, biophysique@pasteur.fr . Instructions and down-loadable forms are available as a support for these applications, which can be made at any time.

Experiments can be carried out according to 3 different schemes: 1) instrument allocation after user training; 2) service provision; 3) scientific collaboration.

The 13 instruments and the know-how of the PFBMI have attracted more than 110 projects altogether, in association with 29 Research Units of the Pasteur Institute (from 9 out of 10 Scientific Departments) and 27 laboratories from other institutions (French or foreign), leading to 28 peer-reviewed publications.

Below is a very small sample of subjects covered by scientific collaborations and having lead to publications:

* Elucidation of the role of several post-translational modifications in the tethering of protein HP1 to histone tails

* Characterization of the coupling between the trimerization of the rabies virus glycoprotein and its interaction with nerve growth factor receptor p75^NTR

* Determination of the effect of natural pathogenic mutations of the NF-κB modulator protein NEMO on its stability and oligomerization properties

* Calorimetric characterization of the oligomeric structure of E. coli GMP kinase

* Optimization of the determination of the secondary structure of proteins by ATR infrared spectroscopy

* Federative Horizontal Program on Mycobacterium tuberculosis target discovery and drug design