Based on the comprehensive membrane protein production platform established through years of experience, scientists form Creative Biostructure can offer tailored Mempro™ major intrinsic protein (MIP)/formate-nitrite transporter (FNT) superfamily production services using detergent-free expression system.
MIPs are a large superfamily of transmembrane protein channels that are found in bacteria, eubacteria, archaea, fungi, plants and animals. The MIP superfamily is divided into three subfamilies: aquaporins (AQP), aquaglyceroporins and S-aquaporins. Members of FNT superfamily can act as anion channels, and which contain a structural domain termed the aquaporin helical fold. Most FNTs have been classified as: formate channels (FocA and FdhC), hydrogen sulphide channels (HSC), and nitrite channels (NirC). The Transport Classification Database (TCDB) show that the FNT superfamily is included in the MIP superfamily. Traditional approaches for transmembrane protein purification need extraction from the membrane into detergent micelles. However, detergent can induce conformational change on transmembrane proteins. Our renewed detergent-free expression system can best preserve the native conformation of MIP/FNT superfamily proteins for further structural studies.
Figure 1. The interactions between protein and lipid in MIP channels. (Methods Enzymol., 2015)
Creative Biostructure has exteinsive expertise in high quality MIP/FNT superfamily production using detergent-free membrane protein expression system, we can employ various strategies for Mempro™ detergent-free protein production, including:
Nanodiscs are the self-assembly system to stabilize membrane proteins removed from the membrane by membrane scaffold proteins (MSPs) in absence of detergent. Creative Biostructure can reconstitute MIP/FNT superfamily proteins into nanodiscs in detergent-free process: Expressing the MIP/FNT superfamily proteins in a cell-free system with the addition of pre-assembled nanodiscs.
The amphipathic amphipols have the ability to “trap” around transmembrane regions of proteins, allowing them to stay folded. Creative Biostructure can use A8-35 to solubilize MIP/FNT superfamily proteins during purification step.
The SMALPs are self-assembled by the simple addition of the SMA co-polymers. At neutral or alkaline pH, a disc-like structure assembles itself, encapsulating MIP/FNT superfamily proteins in a form amenable to be purified.
These novel detergent-free approaches for MIP/FNT superfamily production can be obtained easily, and enabling more comprehensively structural and functional studies.
Creative Biostructure provides other various Mempro™ membrane protein production services. Please feel free to contact us for a detailed quote.
C. Tribet, et al. (1996). Amphipols: Polymers that keep membrane proteins soluble in aqueous solutions. Proc Natl Acad Sci U. S. A. 93: 15047-15050.
M. Jamshad, et al. (2011). Surfactant-free purification of membrane proteins with intact native membrane environment. Biochem. Soc. Trans., 39: 813-818.
N. Yan (2015). Structural biology of the major facilitator superfamily transporters. Annu. Rev. Biophys., 44: 257-283.
R. K. Verma, et al. (2015). Major intrinsic protein superfamily: channels with unique structural features and diverse selectivity filters. Methods Enzymol., 557: 485-520.