Development and Optimization of Endolysins Purification Process to Fight against Antimicrobial Resistant S. aureus Bacteria
Summary
Biopharmaceutical Biotechnology
Public
Micreos GmbH, Zugerstrasse 76, Wädenswil, CH-8820, Switzerland
Carmen Jungo Rhême
Skills directory
December 2024 - October 2025
The project aims to develop a standardized, industrially scalable process for purifying recombinant endolysins produced intracellularly in genetically modified E. coli. Production will be carried out in 5L fed-batch cultures using a strain from Micreos, with a focus on transitioning from a semi-defined to a fully chemically defined medium to reduce variability and impurities. The purification process will involve cell lysis by sonication, followed by chromatography (including cation exchange), ultrafiltration/diafiltration, and potentially additional steps for endotoxin removal. Initial upstream and downstream process steps have already been successfully implemented at the Biofactory Competence Center (BCC).
This project will contribute to the further development of a robust process for the purification of recombinant endolysins expressed intracellularly with E. coli strains. Endolysins have shown great potential as an alternative to traditional antibiotics, especially in combating multi-resistant bacteria.
After successful technology transfer of the current lab-scale purification process used by the Discovery Labs of Micreos Pharmaceuticals located in Wädenswil to the Biofactory Competence Center, the different purification process steps, including mainly chromatography and ultrafiltration/diafiltration steps, will be further developed and optimized taking into account industrial scalability and regulatory aspects.
The recombinant endolysins will be produced under well-controlled growth conditions in state-of-the-art bioreactors including on-line monitoring and control of critical process parameters. The use of fully chemically defined medium was evaluated first to exclude undefined components like yeast extract with the goal to ensure consistent and reproducible results, as well as to minimize process-related impurities. Downstream purification steps are optimized by identifying the process parameters that have the greatest influence on product yield and quality.