Based on the comprehensive membrane protein production platform established through years of experience, scientists from Creative Biostructure can offer tailored Mempro™ peptide fragments of water-soluble proteins production services using detergent-free expression system.
Peptide fragments of water-soluble proteins is a superfamily which consists of 10 protein families as shown in the following table.
Major Prion protein
Viral protein R
Human immunodeficiency virus type 1
Amyloidogenic peptide of phosphatase
Litopenaeus vannamei (Whiteleg shrimp)
Table 1. Families in the peptide fragments of water-soluble proteins superfamily.
Viral protein R also named Vpr is a Human immunodeficiency viral gene and protein product. It is a 14-kDa protein with 96 amino acids and is crucial in the process of regulating nuclear import of the HIV-1 pre-integration complex. G2 cell cycle arrest and apoptosis in proliferating cells are induced by Vpr, the process of which may lead to immune dysfunction. Vpr is also immunosuppressive due to its capacity to isolate a proinflammatory transcriptional activator in the cytoplasm. Moreover, Vpr is needed for virus replication in non-dividing cells such as macrophages. HIV-2 includes a Vpr protein and a correlative (by sequence homology) Vpx protein (viral protein x).
Figure 1. The structure of viral protein R. (Nano Letters, 2002)
Creative Biostructure has extensive expertise in high quality peptide fragments of water-soluble proteins production using detergent-free membrane protein expression system, we can employ various strategies for Mempro™ detergent-free protein production, including:
Nanodiscs are soluble nanoscale phospholipid bilayers, which are composed of membrane scaffold proteins (MSPs). They provide an inartificial phospholipid bilayer environment for target membrane proteins in the solubilized state. Otherwise, nanodiscs are under the existence of phospholipids and MSPs, meanwhile they are generally used for structural, enzymatic and biophysical researches. The structure of nanodiscs is extremely similar to high-density lipoproteins (HDL).
Amphipols are absolutely practicable tools for handling membrane proteins in detergent-free water solutions, and essentially it’s a new class of surfactants. Besides, amphipols enable to stabilize in aqueous solution with their inartificial nature state four well-authenticate integral membrane proteins.
SMALPs are disc-like structures including a protein in a lipid bilayer, parceled by the amphipathic styrene maleic acid polymer (SMA). Compared with nanodiscs, bicelles and amphipols, the most significant advantage of SMALPs is that there is no need to extract proteins from membranes with possibly destabilizing detergents.
These novel detergent-free approaches for peptide fragments of water-soluble proteins 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.
Bayburt, T. H., Grinkova, Y. V., & Sligar, S. G. (2002). Self-assembly of discoidal phospholipid bilayer nanoparticles with membrane scaffold proteins. Nano Letters, 2(8), 853-856.
Bayburt, T. H., & Sligar, S. G. (2010). Membrane protein assembly into Nanodiscs. FEBS letters, 584(9), 1721-1727.
Skar-Gislinge, N., Simonsen, J. B., Mortensen, K., Feidenhans’l, R., Sligar, S. G., Lindberg Møller, B., Arleth, L. (2010). Elliptical structure of phospholipid bilayer nanodiscs encapsulated by scaffold proteins: casting the roles of the lipids and the protein. Journal of the American Chemical Society, 132(39), 13713-13722.
Tribet, C., Audebert, R., & Popot, J.-L. (1996). Amphipols: polymers that keep membrane proteins soluble in aqueous solutions. Proceedings of the National Academy of Sciences, 93(26), 15047-15050.