Cum Laude for chemistry PhD graduate Gaston Richelle

For novel peptide multicyclization strategies enabling next-generation therapeutics

4 December 2018

On Friday 30 November 2018 Gaston Richelle of the Synthetic Organic Chemistry group at the Van 't Hoff Institute for Molecular Sciences successfully defended his PhD thesis on 'Multicyclic peptides manufactured via scaffold-assisted CLIPS/CuAAC technology'. Richelle received his PhD with the distinction 'cum laude', honouring his novel and original research that resulted in landmark papers and has potential for commercial application in combatting infectious diseases.

With this research, Gaston Richelle makes an important contribution to the testing and identification of new active peptides as potential medicines against various complex targets, such as enzymes and bacteria. He has developed a scaffold-assisted technology for the synthesis of multicyclic peptides based on a fairly straightforward one-pot procedure consisting of two orthogonal chemistries, CLIPS and CuAAC. As a result it is now possible to not only synthesize mono- and bicyclic peptides but also more complex tri-, tetra-, penta- and even hexacyclic peptides.

Antimicrobial activity

As a demonstration of the power of the technology, Richelle synthesized and tested a range of 200 tricyclic peptides. Two of these showed antimicrobial activity, one against Staphylococcus aureus (the MRSA bacterium often causing problems in hospitals) and one against Escherichia coli (the human intestinal bacterium found in faeces). Especially the latter peptide proved to be very selective.

Cover of Angewandte Chemie featuring Gaston Richelle's 'hot paper'.

The research presented in Richelle's thesis already led to high impact papers in renowned journals. For example, his paper in Angewandte Chemie was assigned as ‘hot paper’ and was featured on the cover. A follow-up paper in ChemBioChem was also acknowledged with a cover picture, and more papers will follow. Moreover, his research resulted in a patent, which is online since June 2018. 

Richelle is currently working as a senior scientist at Pepscan Therapeutics in Lelystad, the Netherlands, where he will further develop his methodology. Pepscan is a premier provider of peptide-based products together with various drug discovery services i.e. phage display libraries. Pepscan's Chief Scientific Officer Prof. Peter Timmerman supervised Richelle's PhD research along with Prof. Jan van Maarseveen, group leader of Synthetic Organic Chemistry at the Van 't Hoff Institute for Molecular Sciences.

Talented student

Gaston Richelle and his paranymphs Roel Klein Nijenhuis and Maria Luisa Corrado. Photo: HIMS.

Gaston Richelle studied chemistry at the Radboud University (Nijmegen, the Netherlands). For his BSc research project he was awarded the 'Gouden Spatel' in 2010 by KNCV, the professional association of chemists, life scientists and process technologists in the Netherlands. In 2013 he obtained his MSc under supervision of Prof. Floris Rutjes, after which he started his PhD research at the University of Amsterdam's Van 't Hoff Institute for Molecular Sciences. In 2015 he was invited to the Roche Continents conference for top-talented students, and in 2017 he was selected by the American Chemical Society as one of the SciFinder Future Leaders of that year.

Published by  HIMS