Creative Biolabs provides professional detergent-free membrane protein production/reconstitution service using novel polymers technology.
Stabilization of membrane protein is the essential process for membrane protein preparation, which is usually achieved via conventional water-soluble (detergent-lipid-protein) complex method. However, detergent, a kind of surfactants, has the potential risk of inducing subunit disassociation, misfolding, leading to protein denaturation or inactivation. To overcome this issue, an alternative polymer approach is designed to isolate and solubilize membrane protein in most native format, completely without the use of detergents. Currently, Creative Biolabs offers two amphipathic polymer solutions for membrane proteins (purified or not purified) to our global clients:
Amphipols (e.g. A8-35) are synthesized via the formation of amide bonds between octylamine and the carboxylic groups of low-molecular-weight polyacrylic acid precursors. The end-products are co- or terpolymers, in which the grafted side chains or groups are randomly distributed along the main chain. The amphipols have the ability to make the transmembrane regions of proteins “trapped” around by these polymers, so as to keep hydrophobic domains stay folded. Amphipols have been used to successfully solubilize a number of proteins, such as GPCRs, with no biological function change (Figure 1).
Figure 1. An example of amphipol A8-35 purifying procedure. (Zoonens, et al. 2005)
Poly (styrene-co-maleic acid) lipid particles (SMALPs), also a kind of low-molecular-weight chemical, are able to reversibly encapsulate membrane protein. The polymer itself is made of alternating hydrophilic (maleic acid) and hydrophobic (styrene) moieties. SMALPs are ideally suited to purification and further biochemical studies (such as drug discovery) due to its characteristics of high-temperature resistance and pH sensitivity. The SMALPs are synthesized by the simple addition of SMA co-polymer to the membrane circumstance containing the protein of interest. At neutral or alkaline pH, a disc-like structure assembles itself, encapsulating the membrane protein in a form amenable to be purified. At acidic pH, the polymer disassociates from the particle to leave the membrane protein containing complex alone (Figure 2).
Figure 2. Diagrammatic representation of lipid and membrane protein encapsulation by SMALPs. (Jamshad, et al. 2011)
Creative Biolabs now offers all-around, custom-oriented service of Magic™ membrane protein production. We are more than happy to leverage our advanced techniques and extensive expertise in this field to satisfy every single custom demand. Please feel free to contact us for more details.