Protein Purification

Our expertise extends beyond purifying tagged proteins. We are particularly experienced at purifying non-tagged proteins from recombinant sources and fresh plant and animal tissues.

Before starting a protein purification we do a complete in silico work up that includes:

A BLAST search to identify similar proteins and then a literature search for articles describing the purification of the target and/or related proteins.

In addition to the usual parameters such as isoelectric point, we look for structural homologues and 3D structures to gain some understanding of surface charge distributions as they affect the types and order of chromatographic media used in the purification.

Micro Scouting - once we have a strategy in place we test it on a micro scale using a variety of buffer conditions to verify the strategy. We even micro scout conditions for Ni-NTA binding of a His-tagged proteins since salt and pH adjustments can make a difference.

We have multiple automated chromatography systems for:

Affinity Chromatography - Metal chelate (Ni-NTA), anti-FLAG & GST-fusions.

Ion Exchange Chromatography (IEX) - Q, DEAE, SP, CM-Sepharoses.

Hydrophobic Interaction Chromatography (HIC) - phenyl, butyl, octyl-Sepharoses.

Hydroxyapatite (HA) - PO4, NaCl/KCl, MgCl2 work up on microcrystalline or ceramic-supported media.

Size Exclusion Chromatography on various Sephacryl and Superdex media.

Milligram to Gram Scale Quantities.