Proteomics often starts from a mixture of proteins while only some of them might be of interest to you. Therefore, protein fractionation or depletion can be desirable. This can be performed in many ways at ProGenTomics:
- based on molecular weight: ultrafiltration, size-exclusion chromatography, gel (SDS-PAGE)
- based on specific ligand: affinity chromatography (for example purification of His-tag labelled proteins)
- based on charge: ion exchange chromatography
- based on hydrophobicity: reversed phase chromatography
- based on abundance: Proteominer protein enrichment technology to dilute abundant proteins and concentrate low-abundant proteins
Chromatography experiments are performed on an ÄKTA purifier 10 (GE Healthcare).
Advantages of protein separation
- Can be used to isolate a (set of) protein(s) of interest
- Makes it possible to dig deeper into the proteome in broad screening experiments, leading to more identified proteins
Workflow
You provide us with your protein mixture of interest with the exact composition of the buffer. Depending on the chosen separation technique a protein quantification will be performed upfront. The number of fractions can be determined by the customer.
Prior to any chromatographic separation on the ÄKTA purifier, samples will be filtered (0.45 µm) and centrifuged. Purified fractions will be collected in falcon tubes or protein lo-bind eppendorfs. For protein separation by gel (SDS-PAGE), the composition of the buffer should be mentioned and the salt concentration of the samples should be as low as possible.