PEPCF expresses proteins in bacteria, insect and mammalian cells and uses a variety of chromatographic and biophysical techniques for protein purification and characterization.
A large variety of methods is available to lyse cells. Which of these methods is the most optimal one depends on the type of host cells and on the quantity of cells to be lysed. The table below gives an overview of commonly used cell lysis methods and their respective advantages and disadvantages.
| Technique | Principle | Advantages | Disadvantages |
|---|---|---|---|
| Liquid shear pressure: * French press * Homogenizer | Rapid high pressure to low pressure | * Suitable for large volumes * Fast, efficient | Cooling required |
| Ultrasonication | High frequency sound | Easy | * Not for large volumes * Heating up of sample * Can destroy sensitive proteins |
| Freeze / Thawing (+ enzymatic lysis, e.g. lysozyme) | Ice crystals | * Cheap * Easy | * Low yield * Slow * Can damage sensitive proteins (or protein complexes) |
| Glass beads | Mechanical | Good for yeast | Slow |
| Osmotic shock | High to low osmolarity | * Easy * Periplasmic extraction | Only for non-robust cells (e.g. mammalian cells) |
| Chemical lysis | Detergents-based | * High throughput * Easy | Expensive (commercial ones: BPER, BugBuster…) |