Membrane protein production

Unlocking membrane protein research

Our protein scientists have optimised a screening platform to identify the best approach to purify your membrane protein, whether that is a detergent-based or detergent-free strategy.

Membrane proteins such as ion channels, GPCRs and transporters are key targets for drug discovery. The transmembrane regions of such proteins interact directly with the membrane phospholipid bilayer, enabling them to perform tasks such as transporting ions and small molecules, or relaying signals from extracellular stimuli to the internal environment of the cell. 

Despite the prominent role played by membrane proteins in multiple disease modalities, membrane protein drug discovery remains challenging. Extraction of membrane proteins is critical to elucidating their structural and functional roles within complex biological systems. However, their localisation and the hydrophobic nature of transmembrane regions presents unique challenges in purifying correctly folded and functional protein samples for use in drug discovery. Our experienced team can support all aspects of your membrane protein programme from protein expression and purification, atomic structure determinationcompound design and synthesis, through to cell-based and biophysical screening.

Membrane protein molecular image

Customised Protein Production

  • Protein expression:
    • Custom construct design
    • Multiple expression systems (E.coli, insect and mammalian cells)
    • Co-expression of multi-protein complexes (e.g. GPCR-Gαβγ complexes)
    • In vivo biotinylation for downstream screening applications
  • Solubilisation methods:
    • Detergents
    • Polymer native nanodiscs
  • Protein purification:
    • Affinity chromatography
    • Size exclusion chromatography (SEC)
    • Tag cleavage
  • Protein specific QC:

Membrane Protein Applications

Protein can be provided directly to you for your antibody discovery, small molecule drug discovery or structural biology projects:

Protein Expression

Our scientists will work with you to design bespoke expression constructs that suit your downstream applications, including truncations or point mutations and addition of purification/detection tags or stabilising fusions. The constructs can be cloned into a range of vectors for expression in bacterial, insect or mammalian (Expi293™) cells.

Small scale expression studies are performed to identify suitable constructs and an expression host that can be used for optimisation of the solubilisation and purification conditions.

Membrane Protein Solubilisation Methods

At Domainex we are focused on finding the right extraction method for your target and downstream application, be that detergent, or synthetic polymers forming nanodiscs. Our expert scientists have optimised a screening platform to identify detergent-based or detergent-free strategies to purify GPCRs, ion channels and solute carriers to enable drug discovery programmes.

Detergent Extraction

Efficient solubilisation

Detergent extraction

 

Detergent extraction is a traditional and efficient membrane protein extraction method suitable for many downstream applications.

Advantages:

  • Established methods
  • Highly effective at solubilising membrane proteins
  • Suitable for biochemical and biophysical assays 

Polymer nanodiscs

Native-like environment

Polymer Nanodiscs

 

Amphipathic co-polymers, such as SMA, DIBMA, AASTY and amphipols, are able to insert directly into cell membranes and spontaneously form nanodiscs. Proteins embedded in the membrane are excised within these nanodiscs, allowing purification without disrupting the native phospholipid environment.

Advantages:

  • Detergent free
  • Membrane protein is within its natural membrane environment maintaining high biological activity
  • Protein maintains solubility without further addition of polymer or detergents
  • Suitable for biochemical and biophysical assays 

Membrane Protein Case Studies

Cryo-EM analysis of agonist-activated ion channel TrpML3

Ion Channel - Mammalian (Expi293™) expression – Detergent extraction

Cryo Em case study graphs

Adenosine A2a receptor: Fragment screening using Polymer-encapsulated nanodiscs

GPCR - Insect expression (Sf9) – Polymer nanodisc extraction

Adenosine A2a receptor: Fragment screening using Polymer-encapsulated nanodiscs