David Papapostolou's Research Page

Design and structural characterisation of peptide-based self-assembling nanomaterials.

Current work

The aim of my project is to decipher the internal order of our Self-Assembling Fibres (SAFs), in order to be able to control their structural features as well as their stability to external factor such as salt, pH or temperature.

An electron micrograph and X-Ray diffraction pattern of SAFs

(a) Electron micrograph of a SAF, positively stained with uranyl acetate. The scale bar is 100nm.

(b) X-ray diffraction pattern of partially aligned SAFs, the values are in angstroms.

A high dose of peptide design is obviously the sole of my work, as it is our main tool when it comes to assess our understanding and misunderstanding of the systems we are studying. My practice in the lab involves the use of vibrational spectroscopy in order to follow the folding of our peptides into well characterised secondary structures (in my case, mainly alpha helices), as well as electron microscopy and x-ray diffraction to follow the formation of higher-order assemblies.

Previous work

I have done my PhD Thesis work in Pr Michele Reboud-Ravaux's Laboratoire d'Enzymologie Moleculaire et Fonctionnelle (Institut Jacques Monod, Paris). I have been concentrating on the design of short peptides and small molecules as proteases inhibitors, as potential new drugs for the treatment of cancer and inflammation. My part of the works was the design of these molecules and/or the enzymatic characterisation of their effects on the eukaryote proteasome (ubiquitous multi-catalytic complexe) [1-3], as well as MMPs and urokinase [4].

[1] Papapostolou D, Basse N, Pagano M, Reboud-Ravaux M, Bernard E, Felten AS, Vanderesse R (2006) "evelopment of lipopeptides for inhibiting 20S proteasomes", Bioorg Med Chem Lett. Jun 15;16(12):3277-3281.

[2] Papapostolou D, Reboud-Ravaux M (2006) "Proteasome and proteolysis", J Soc Biol, 198(3):263-78.

[3] Papapostolou D, Coux O, Reboud-Ravaux M (2002) "Regulation of the 26S proteasome activities by peptides mimicking cleavage products", Biochem Biophys Res Commun, Aug 2;295(5):1090-5.

[4] Kempen I, Papapostolou D, Thierry N, Pochet L, Counerotte S, Masereel B, Foidart JM, Reboud-Ravaux M, Noel A, Pirotte B (2003) "3-Bromophenyl 6-acetoxymethyl-2-oxo-2H-1-benzopyran-3-carboxylate inhibits cancer cell invasion in vitro and tumour growth in vivo", Br J Cancer. 2003 Apr 7;88(7):1111-8.