Based on the comprehensive protein engineering platform established through years of experiences, scientists form Creative Biostructure provides costum Mempro™ protein production services for annexins based on cell-free expression system.
Mempro™ cell-free protein production system is the innovated system to produce membrane proteins, which overcome the difficulties that encountered in cell-based production system, such as host cell toxicity, low yield and solubilization and purification using detergents. Annexins are a family of Ca2+/phospholipid-binding proteins that are mostly found in eukaryotic organisms. The significant characteristic of annexins is their Ca2+-regulated binding to the periphery of cell membranes containing acidic phospholipids. The conserved Ca2+- and membrane-binding module is the annexin core domain, which is composed of four annexin repeats, each of which is around 70 amino acids in length. Annexin repeats have the surface containing the Ca2+- and membrane-binding sites, which also play important roles in vesicle transport and calcium ion channel formation. In vertebrates, twelve annexin subfamilies (A1-A11 and A13) have been identified.
Figure 1. Model of membrane domain stabilization mediated by annexin A2. (J. Cell Sci., 2004)
Creative Biostructure has rich experience in high-quality annexins production using cell-free protein expression system, we can provide various strategies for Mempro™ cell-free protein production, including:
Among Mempro™ cell-free membrane protein production systems, E. coli S30 extract is widely used for annexins production. Wheat germ extract can provide eukaryotic translation system for annexins expression. Baculovirus expression system from Autographa californica nucleopolyhedrovirus (AcNPV) is also a major system for annexins expression. Rabbit reticulocyte lysate is an important tool for eukaryotic cell-free integral membrane protein expression. To employ an appropriate source of the extract, many factors, such as the availability of materials, protein origin and complexity, downstream processing, etc., should be considered. Of note, one challenge associated with MemproTM cell-free membrane protein production is that degradation of the DNA by endogenous nucleases. Creative Biostructure can optimize MemproTM cell-free membrane protein production for annexins using plasmids due to they are circular and have no end for the exonucleases to attach.
With the Mempro™ cell-free protein production platform, Creative Biostructure are capable of expressing, purifying and crystallizing annexins to perform further structural and functional studies.
Creative Biostructure provides other various Mempro™ membrane protein production services. Please feel free to contact us for a detailed quote.
F. Bernhard, et al. (2013). Cell-free expression - making a mark. Cur. Opin. Struct. Biol., 23: 374-380.
U. Rescher and V. Gerke (2004). Annexins - unique membrane binding proteins with diverse functions. J. Cell Sci., 117: 2631-2639.
V. Gerke and S. E. Moss (2002). Annexins: from structure to function. Physiol. Rev., 82(2): 331-371.