A practical reference on recombinant-protein: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-09-16. Anything still debated is marked as such rather than presented as settled.
Affimers are recombinant proteins. As they are manufactured using recombinant bacterial production processes, the batch-to-batch consistency for Affimers is improved compared to polyclonal antibodies, overcoming some of the issues of reproducibility and security of supply. These synthetic antibodies were engineered to be stable, non-toxic, biologically neutral and contain no post-translational modifications or disulfide bridges. Two separate loop sequences, incorporating a total of 12 to 36 amino acids, form the target interaction surface so interaction surfaces can range form 650–1000 Å. The large interaction surface results allows binding to target proteins. Affimer technology has been commercialised and developed by Avacta, which is developing these affinity reagents as tools for diagnostics and as biotherapeutics.
Immobilized metal ion affinity chromatography (IMAC) is based on the specific coordinate covalent bond of amino acids, particularly histidine, to metals. This technique works by allowing proteins with an affinity for metal ions to be retained in a column containing immobilized metal ions, such as cobalt, nickel, or copper for the purification of histidine-containing proteins or peptides, iron, zinc or gallium for the purification of phosphorylated proteins or peptides. Many naturally occurring proteins do not have an affinity for metal ions, therefore recombinant DNA technology can be used to introduce such a protein tag into the relevant gene. Methods used to elute the protein of interest include changing the pH, or adding a competitive molecule, such as imidazole.
Recombinant DNA technology arose as a result of advances in biology that began in the 1950s and '60s. During these decades, a tradition of merging the structural, biochemical, and informational approaches to the central problems of classical genetics became more apparent. Two main underlying concepts of this tradition were that genes consisted of DNA and that DNA encoded information that determined the processes of replication and protein synthesis. These concepts were embodied in the model of DNA produced through the combined efforts of James Watson, Francis Crick, Rosalind Franklin, and Maurice Wilkins. Further research on the Watson-Crick model yielded theoretical advances that were reflected in new capacities to manipulate DNA. One of these capacities was recombinant DNA technology.
ADAMTS7 was identified as a protease that binds and cleaves COMP in a yeast two-hybrid screen using the epidermal growth factor (EGF) domain of COMP as the bait. However, this initial finding has been contested; a 2025 study demonstrated that purified ADAMTS7 does not exhibit proteolytic cleavage activity toward purified COMP. Furthermore, three independent unbiased N-terminal amine isotopic labeling of substrates (N-TAILS) proteomic studies identified a number of candidate substrates for ADAMTS7 but did not identify COMP as a potential substrate. Consequently, there is as yet no scientific consensus on the physiological function of ADAMTS7. Tissue inhibitor of metalloproteinases 4 (TIMP-4) appears to be the physiological inhibitor of ADAMTS7.
Sources: en.wikipedia.org
Biopharmaceuticals may be produced from microbial cells (e.g., recombinant E. coli or yeast cultures), mammalian cell lines (see Cell culture) and plant cell cultures (see Plant tissue culture) and moss plants in bioreactors of various configurations, including photo-bioreactors. Important issues of concern are cost of production (low-volume, high-purity products are desirable) and microbial contamination (by bacteria, viruses, mycoplasma). Alternative platforms of production which are being tested include whole plants (plant-made pharmaceuticals).
Blood factors (Factor VIII and Factor IX) Thrombolytic agents (tissue plasminogen activator) Hormones (insulin, glucagon, growth hormone, gonadotrophins) Haematopoietic growth factors (Erythropoietin, colony-stimulating factors) Interferons (Interferons-α, -β, -γ) Interleukin-based products (Interleukin-2) Vaccines (Hepatitis B surface antigen) Monoclonal antibodies (Various) Additional products (tumour necrosis factor, therapeutic enzymes) Research and development investment in new medicines by the biopharmaceutical industry stood at $65.2 billion in 2008. A few examples of biologics made with recombinant DNA technology include: Many vaccines are grown in tissue cultures. Viral gene therapy involves artificially manipulating a virus to include a desirable piece of genetic material. Viral gene therapies using engineered plant viruses have been proposed to enhance crop performance and promote sustainable production.
Possibly the most common use of affinity chromatography is for the purification of recombinant proteins. Proteins with a known affinity are protein tagged in order to aid their purification. The protein may have been genetically modified so as to allow it to be selected for affinity binding; this is known as a fusion protein. Protein tags include hexahistidine (His), glutathione-S-transferase (GST), maltose binding protein (MBP), and the Colicin E7 variant CL7 tag. Histidine tags have an affinity for nickel, cobalt, zinc, copper and iron ions which have been immobilized by forming coordinate covalent bonds with a chelator incorporated in the stationary phase. For elution, an excess amount of a compound able to act as a metal ion ligand, such as imidazole, is used. GST has an affinity for glutathione which is commercially available immobilized as glutathione agarose. During elution, excess glutathione is used to displace the tagged protein. CL7 has an affinity and specificity for Immunity Protein 7 (Im7) which is commercially available immobilized as Im7 agarose resin. For elution, an active and site-specific protease is applied to the Im7 resin to release the tag-free protein.
Sources: en.wikipedia.org