Getting Started
You want to purify proteins and you’re going to use gravity columns with affinity resin. This protocol will show you how to set up these columns.
We use Ni-His columns to purify PURE proteins. These columns are packed with microscopic gel beads containing covalently bound Ni in their interior. This resin specifically bind proteins with a poly Histidine tag (e.g., 6xHis). The His residues chelate the Ni and bind tightly. Proteins are then eluted with Imidazole, which competes with the His tags to chelate Ni.
Materials and Equipment
Name | Product | Manufacturer | Part # | Price | Storage Conditions | Link |
Columns | ||||||
Gravity columns | Empty Disposable PD-10 Columns | Cytiva | 17043501 | $258.30 | 4C to 30C | [link] |
Resin | ||||||
Ni-His Resin | NEBExpress Ni Resin | New England Biolabs | S1428S | $358.00 | 1C to 4C | [link] |
Buffers | ||||||
Potassium Hydroxide | Potassium hydroxide - ACS reagent, ≥85%, pellets | Sigma-Aldrich | 221473-1KG | $99.90 | 4C to 30C | [link] |
Hydrochloric acid (1M) | Hydrochloric acid 1 N, Reagent Grade, Packaging=Amber Bottle, Size=500 mL | VWR | E447-500L
| $72.46 | 4C to 30C | [link] |
HEPES | HEPES, Crystalline Powder, ≥99.5% (titration), Poly bottle | Sigma-Aldrich | H3375-500G | $431 | 4C to 30C | [link] |
Imidazole | ReagentPlus® Imidazole, Crystalline, 99% | Sigma-Aldrich | I202-500G | $120 | 4C to 30C | [link] |
Ammonium Chloride | Ammonium chloride,ACS reagent, ≥99.5% | Sigma-Aldrich | 213330-500G | $73.50 | 4C to 30C | [link] |
Sodium Chloride | Sodium Chloride, Redi-Dri™, anhydrous, free-flowing, ACS, ≥99% | Sigma-Aldrich | 746398-1KG | $133.00 | 4C to 30C | [link] |
Magnesium Chloride hexahydrate | BioXtra Magnesium chloride, Hexahydrate, Powder or Crystals, ≥99.0% | Sigma-Aldrich | M2670-100G | $50.50 | 4C to 30C | [link] |
TCEP-HCl (0.5M; presuspended) | Thermo Scientific, Bond-Breaker® Tris[2-Carboxyethyl]phosphine Neutral Solution (TCEP), Application=Water-Soluble Reducing Agent, Molecular Weight=286.65, Size=5 mL | Thermo Scientific | 77720 | $175.65 | 4C to 30C | [link] |
Protocol
Prepare Stock Solutions and P1 Wash Buffer as specified in
Make Protein Purification Buffers and Media
Assemble columns.
Cut tips off of columns off using scissors or a razor blade.
Pack a filter into the bottom of the column (we use the back end of a cell spreader).
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Wash empty columns.
Clamp columns to a lab stand and put a large beaker (≥ 500 mL) underneath to capture flowthrough.
Wash columns and filters with 10 mL Ultrapure water.
Load and Equilibrate Ni2+ affinity Resin into columns
Resuspend Ni2+ resin (50% v/v suspension) by shaking.
Add 2 mL resin by pipette to each column.
Equilibrate columns with 10 CV of cold P1 Wash Buffer (4C) and discard flowthrough.
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Store Columns.
Seal each column with a cap and bung.
Store columns at 4C for up to 48 hrs.
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Resources and References
- Papers
- Original PURE paper
- OnePot PURE
Credits
Yan Zhang, Zoila Jurado, and Miki Yun (Richard Murray Lab, Caltech)
- Developers