Soutenance d’HDR de Marco Ribezzi

21 juin 2022 9:30 » 12:30 — Charpak

Soutenance HDR de Marco Ribezzi, Protein Engineering chez ESPCI Paris - PSL

Resume : Directed evolution for Single-Molecule Technologies


Directed evolution is an experimental approach that mimics Darwinian dynamics by creating a molecular ’niche’ to which populations can adapt through iterative rounds of mutation and screening or selection.
By carefully tuning the properties of the niche, directed evolution can be used to investigate evolutionary dynamics, and to evolve nucleic acids and proteins for research, diagnostic, and therapeutic applications.

Directed evolution (and protein engineering in general) have had a great impact on biotechnology and in particular on sequencing techniques. From classical Sanger sequencing to modern approaches, it is hard to find a method that does not rely on engineered enzymes. Several actors in the fields of nucleic acid and peptide sequencing are currently developing methods that rely on the direct observation of the stochastic dynamics of individual enzymes. These single-molecule technologies pose a problem to standard directed evolution approaches because existing methods rely on bulk measurements, typically based on only a single parameter.

It is thus hard to screen or select based on subtle phenotypic traits, such as functional promiscuity and conformational or kinetic heterogeneity. Nevertheless, traits are extremely important in applications and can also play important evolutionary roles.


In the talk, I will review my work on the directed evolution of proteins for nucleic acid and protein sequencing, highlighting the power of conventional approaches as well as their limitations. Moreover, I will discuss how, combining expertise from the fields of directed evolution and single-molecule microscopy, we are trying to develop a novel directed evolution system, based on single-molecule phenotyping and genotyping, which overcomes many of these limitations.

Infos pratiques :
Le 21/06 à 10h dans l’amphithéâtre Charpak, ESPCI Paris - PSL
10 Rue Vauquelin, 75005 Paris,
Batiment J, rez-de-chaussée, à gauche juste après l’accueil.

Haut de page