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Early Viral Entry Assays for the Identification and Evaluation of Antiviral Compounds
Published on: October 29, 2015
Protein modification during antiviral heat bioprocessing
C M Smales1, D S Pepper, D C James
1Research School of Biosciences, University of Kent at Canterbury, Canterbury CT2 7NJ, Kent, UK. c.m.smales@ukc.ac.uk
Biotechnology and Bioengineering
|December 11, 1999
Summary
Viral inactivation via heat treatment can modify therapeutic proteins. This study shows wet-heat treatments, especially with sucrose, cause glycation in lysozyme, impacting protein quality.
Area of Science:
- Biopharmaceutical manufacturing
- Protein chemistry
- Viral inactivation
Background:
- Heat treatment is crucial for viral inactivation in biopharmaceutical production.
- Maintaining protein integrity during heat treatment is a key challenge.
- Balancing viral kill with protein quality requires understanding modification pathways.
Purpose of the Study:
- To investigate protein modifications in hen egg-white lysozyme under various heat treatment conditions.
- To explore the impact of formulation (sucrose) and heat type (wet/dry) on protein integrity.
- To identify specific covalent modifications occurring during antiviral heat treatments.
Main Methods:
- Utilized hen egg-white lysozyme as a model protein.
- Applied industrially relevant wet- and dry-heat treatments with sucrose formulations.
- Employed liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and peptide mapping for analysis.
Main Results:
- No aggregation or crosslinking of lysozyme was observed.
- Wet-heat treatments induced covalent modifications, primarily glycation at Lys(97).
- Glycation involved glucose or fructose from hydrolyzed sucrose; fructose led to more advanced glycation end products (AGEs).
Conclusions:
- Heat treatment conditions significantly influence protein modification, particularly glycation.
- Sucrose hydrolysis and subsequent glycation are key concerns in wet-heat processing.
- Understanding these modifications is vital for optimizing bioprocesses and ensuring therapeutic protein quality.
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