Creative Biolabs has integrated multiple cutting-edge technologies and established a powerful Magic™ membrane protein antibody platform. In addition to antibody generation, our scientists are also specialized in producing high-quality membrane protein products (both membrane crude or purified proteins) for immunogen preparation, assay development, and various other applications.
Membrane proteins, which constitute over thirty percent of all proteins in human genome, play a vital role in many cellular functions like materials transportation, signal transduction, intercellular recognition ligand-receptor binding, cell adhesion, etc. As such, they represent the absolute majority (over 60%) of current drug targets. Due to their low natural abundance and highly complicated structure (partially or completely associated with plasma membrane), to obtain recombinant membrane protein products with native confirmation and bio-activity has always been a challenging issue.
During the past decade, scientists in Creative Biolabs have devoted to various optimizations and exploration to process development of membrane protein expression, solubilization, purification, and characterization. Our versatile Magic™ membrane protein platform employs diverse state-of-the-art techniques to pursue the best-quality membrane protein products With years of experience, we have gained remarkable success in obtaining a variety of difficult membrane proteins such as G-protein coupled receptors (GPCRs), ion channels, membrane transport proteins, etc.
Magic™ membrane protein platform offers extremely flexible options for expression, solubilization, reconstitution, and characterization, including but not limited to:
The cell-based heterogeneous expression is the most commonly used approach for recombinant proteins. For membrane proteins, it can be problematic as for adequate expression levels, correct membrane insertion, and native confirmation preservation. Using our proprietary vector designs and special protocols, we have successfully generated a broad spectrum of targets. Our impeccable platforms can provide multiple options of host organisms, including:
Instead of using integral cell systems, a cell-free platform which is derived from modified cellular extracts, exert unique beneficial feature for expressing many challenging or “difficult” target, especially multipass membrane proteins or toxic proteins. This highly robust, efficient and controllable system can also be directly reconstituted with lipids or nanodiscs, avoiding the use of detergent. Creative Biolabs now provides versatile cell-free expression service using following systems:
Virus-like particles (VLPs) are multiprotein structures that mimic the organization and conformation of authentic native viruses but lack the viral genome (non-infectious). They are widely applied in vaccinology, immunology, and virology. Currently, we offer VLP construction and purification service in various systems, including bacterial, insect, mammalian, etc. PTMs can also be incorporated.
Membrane Protein Stable Cell Lines
Notably, except recombinant expression, Creative Biolabs is also professional in constructing membrane protein overexpressing stable cell lines. Currently, we have over 200 GPCR/ion channel stable cell lines (CHO/HEK background) with high expression levels up to 5 million per cell. These elegant cell lines can be directly used for membrane isolation, immunization and various assays (like SPR), which significantly saves valuable research time.
Detergent-solubilization is a routine procedure for membrane protein isolation in most cases. Selection of appropriate detergent is very crucial as misuse of detergent might compromise protein structure, resulting in denatured products. With our unique reagents as well as other commercially available detergents, we can perform up to 20 solubilizing conditions to screen for the best outcome. As an alternative, we also offer detergent-free plan using our cell-free platform.
Proteoliposomes are one of the most frequently used formats for stabilizing membrane proteins, which is well applicable to immunization, assays, and diverse usages. We have several different lipid compositions available (natural or artificial) for membrane protein reconstitution. Aided by our well-established protocol and vast experiment, the protein products can be incorporated into lipids with correct folding and high bio-activity.
Similar to proteoliposomes, nanodiscs also aims at stabilizing membrane proteins in mimic lipid bilayer, yet with a more dense environment (formed by membrane scaffold proteins, aka MSPs) that is even closer to natural membrane environment. Therefore, nanodisc technology has several advantages over conventional methods, especially for multipass membrane targets like GPCRs, ion channels, etc.
Creative Biolabs also offers polymer reconstitution service of membrane proteins, using amphipols and poly (styrene-co-maleic acid) lipid particles (SMALPs). Polymer technique can solubilize hydrophobic membrane proteins without detergent, meanwhile maximally preserve native confirmation and bioactivity.
In addition to intact/ full-length membrane proteins, we are also specialized in expressing recombinant peptides/fractions derived from extracellular or intracellular loops. This is particularly suitable for many large, multi-spanner membrane proteins with well-characterized structure. Compared with full-length expression, it will be much easier to obtain recombinant peptide domains of interest, which can also work perfectly in immunization, antibody selection, etc. Moreover, we can also replace the transmembrane domain with a soluble peptide, creating a chimeric soluble protein with indicated extracellular/intracellular domains.
Equipped with multiple leading technologies and abundance expertise, Creative Biolabs is confident in delivering satisfactory membrane protein products with our first-class professional service. We provide quite flexible options about expression, solubilization/reconstitution and purification as well as characterization (such as binding assays, functional assays). A pilot study is strongly recommended to gather some preliminary date, and then we can move to further optimizations and scaling-up stage. Please feel free to contact us for a detailed quote.