Range of Services
Technologies & Know how
Expression Systems
Production Capacities
Molecular Biology
High-Throughput Production
Protein Engineering
Refolding
Purification Methods
Protein Analytics
Other Analytical Services

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Protein Engineering   
 
Bioinformatics
Our custom protein database helps us to gather protein-related information and to capitalize on our accumulated experience.
Combined with classic bioinformatics tools, it allows us
to perform sequence analyses and alignments, molecular modelling or structural predictions and/or optimize the choice of expression vectors, constructs and production parameters.
Through our protein engineering expertise, we can modulate and optimize challenging protein properties such as activity, affinity, selectivity, stability, resistance to proteolytic degradation, and even improve protein expressability and solubility.




 
Proprietary Approaches   
Besides custom protein engineering programmes, we also offer proprietary engineering approaches.

Limited Proteolysis
By using a combination of limited proteolysis, chromatography and mass spectrometry technologies, we can identify and separate individual functional domains (minimal active fragment) within multi-domain proteins (recalcitrant proteins, poorly soluble proteins, mix of folded proteins / locally unfolded proteins / unfolded proteins).
Protein Design
In order to increase the solubility, stability or ability
to crystallize of a given protein, we can use a protein compaction technology based on the deletion of the protein’s non-essential floppy loops.
The resulting functional mini-protein will display a better therapeutic value (therapeutic proteins, antigens) or a superior ability to crystallise (target proteins).
This approach has been successfully applied by Protein’eXpert to both viral antigens for vaccines development and anti-bacterial targets for drug discovery applications.


  

 
Example of Protein Engineering Application   
 
Crystal structure of the PBP2x
Andréa Dessen, Nicolas Mouz, Elspeth Gordon, Julie Hopkins and Otto Dodeberg, (2001) The journal of Chemistry, 276, 45106-45112.

Penicillin-binding proteins (PBPs) are the main targets for ß-lactam antibiotics, such as penicillins and cephalosporins, in a wide range of bacterial species. PBP2x is a primary resistance determinant in Streptococcus pneumoniae, and its modification is an essential step in the development of high level ß-lactam resistance.

To understand such a mechanism, we used our protein engineering tools to improve the solubility of the protein and to solve the X-Ray structure.

 

Protein'eXpert SA - PX'Pharma SA - Zone Minatec Entreprises -
7 Parvis Louis Néel – BP50 F - 38040 Grenoble
Phone: +33 (0)438 023 650 - Fax: +33 (0)476 961 038