Custom service
E. coli Protein Expression & Purification
Most E. coli projects fail on solubility, not on expression — so we screen for it before committing to scale.
E. coli remains the fastest and cheapest route to a recombinant protein, provided the protein does not need glycosylation. The usual failure mode is not low expression but aggregation: the band on the gel is strong and all of it sits in the pellet.
Our workflow starts with a small-scale solubility matrix — host strain, temperature, IPTG concentration, and fusion tag — before any fermentation is committed. If the target stays insoluble, we move to refolding or switch the project to a eukaryotic host and tell you why.
What you receive
- 1–10 mg purified protein, ≥90% by SDS-PAGE.
- Solubility screening report covering the conditions tested.
- Construct map, expression and purification records.
- Optional tag removal, endotoxin testing and lyophilisation.
How the work runs
Construct design
Codon optimisation, tag placement (N- or C-terminal His, SUMO, GST) and cleavage site selection.
Expression screening
BL21(DE3), Rosetta and SHuffle hosts at 16 °C, 25 °C and 37 °C, soluble fraction analysed by SDS-PAGE.
Fermentation
Shake flask or 10–100 L fed-batch fermentation with dissolved oxygen and feed-rate control.
Purification
Ni-NTA or glutathione affinity capture, ion exchange polishing and size exclusion as needed.
QC release
Purity by SDS-PAGE and HPLC, identity by mass spectrometry, endotoxin and concentration reporting.
Specifications & timeline
- Scale
- 0.1 L screening to 100 L fermentation
- Yield
- Typically 5–50 mg/L for soluble targets
- Purity
- ≥90%, ≥95% with polishing step
- Timeline
- 4–6 weeks from gene to purified protein
Reagents to pair with it
- Recombinant ProteinsGrowth factors, cytokines and antigens expressed in E. coli, yeast, insect and mammalian platforms — 10,000+ proteins in stock.
- Native ProteinsPurified from natural sources to keep post-translational modifications and true conformational epitopes intact.
- Monoclonal AntibodiesRecombinant and hybridoma monoclonal antibodies validated for WB, IHC, IF, ELISA and flow cytometry.
Next step
Tell us the target, we will tell you what is feasible
Send the sequence, assay format and sensitivity you need. You will get a technical assessment — recommended platform, timeline and the risks worth knowing before you commit budget.