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Prion protein (PRNP) is a ubiquitous membrane glycoprotein whose abnormal self-replicating, misfolded form is widely believed to cause several central nervous system disorders, together known as Transmissible Spongiform Encephalopathies (TSE). PRNP contains a highly unstable region of five tandem octapeptide repeat. Mutations in PRNP protein’s repeat region as well as elsewhere have been associated with Creutzfeldt-Jakob disease, fatal familial insomnia, Gerstmann-Straussler disease, Huntington disease-like 1, and kuru.

PRND is a membrane glycosylphosphatidylinositol-anchored glycoprotein which exists mainly in testis. PRND is expressed during embryogenesis, although in the central nervous system it is expressed minimally .Mutations in PRND may cause neurological disorders. PRND located on chromosome 20, about 20 kbp downstream of the gene encoding cellular prion protein, to which it is biochemically and structurally analogous.

The recombinant Protein A/G is a genetically engineered protein comprised of 7 IgG-binding domains EDABC-C1C3, corresponding to the Protein A and G domains which are included in the recombinant sequence. The Protein A part is from Staphylococcus aureus segments E, D, A, B and C. The Protein G part is from Streptococcus segments C1 and C3. The recombinant Protein A/G has a broader binding capacity than either Protein A or Protein G alone. The recombinant Protein A/G is ideal for purification of monoclonal or polyclonal IgG antibodies. Protein A/G binds to various human, mouse and rat IgG subclasses such as the human IgG1, IgG2, IgG3, IgG4; mouse IgG2a, IgG2b, IgG3 and rat IgG2a, IgG2c. In addition, Protein A/G binds to total IgG from cow, goat, sheep, horse, rabbit, guinea pig, pig, dog and cat.

Protein A is a cell wall protein deriving from Staphylococcus aureus which exhibits unique binding properties for IgG from a variety of mammalian species and for some IgM and IgA as well. It binds with the Fc region of immunoglobulins through interaction with the heavy chain. It couples to a wide variety of reporter molecules including fluorescent dyes, enzyme markers, biotin, colloidal gold and radioactive iodine without affecting the antibody binding site. Recombinant Protein A was developed to increase the specificity of the molecule for IgG and is widely used both in research and bioprocessing. The recombinant protein A is produced by expressing a modified protein A gene in E.coli. A specific purification process with strict quality control was taken to get the recombinant protein A with the purity of more than 98% , no human IgG affinity step is used during validated fermentation and purification and devoid of bacterial contaminant found normally in native Protein A. (Free of Staphylococcus endotoxins and hemolysin).

Recombinant Protein A/G fusion protein joins IgG binding domains of both Protein A and Protein G.
Protein A/G includes four Fc binding domains from Protein A and two from Protein G, yielding a final mass of 50.4 kDa. The binding dependency to pH of Protein A/G lower than Protein A, but has the additive properties of Protein A and G together. Protein A/G binds to all subclasses of human IgG, making it helpful for purifying polyclonal or monoclonal IgG antibodies whose subclasses have not been identifieed. Protein A/G binds to IgA, IgE, IgM and IgD. Protein A/G binds to all subclasses of mouse IgG excluding mouse IgA, IgM or serum albumin. This permits Protein A/G to be used in purification and detection of mouse monoclonal IgG antibodies, with no interference from IgA, IgM and serum albumin. Mouse monoclonal antibodies normally have a stronger affinity to the chimeric Protein A/G than to either Protein A or Protein G. Protein A/G also has been used for purification of macaque IgG.

The recombinant Protein A/G/L is a genetically engineered protein which combines the IgG binding profiles of all Protein A, Protein G and Protein L. Protein A/G/L is a gene fusion product. Recombinant fusion protein A/G/L is comprised of 5 Ig-binding regions of protein L (B1-B2-B3-B4-B5), 5 IgG binding domains from Protein A (E-D-A-B-C) and 2 Ig-binding region of protein G (C1-C3). The recombinant Protein A/G/L is ideal for purification of monoclonal or polyclonal IgG antibodies. Protein A/G/L binds to IgG from humans, mice, rats, cows, goats, sheep, rabbits, guinea pigs, pigs, dogs and cats.

Pirin (PIR) which belongs to the cupin superfamily, is an Fe(II)-containing nuclear protein expressed in all tissues of the body and concentrated within dot-like subnuclear structures. Pirin may function as a transcriptional cofactor and is involved in the regulation of DNA transcription and replication, as a result of interactions with nuclear factor I/CCAAT box transcription factor as well as B cell lymphoma 3-encoded oncoprotein.

Transmembrane protein PRRT2 holds a proline-rich domain in its N-terminal half. PRRT2 is known to be primarily expressed in brain and spinal cord in embryonic and postnatal stages. Alterations in this gene are the cause for paroxysmal kinesigenic dyskinesia. PRRT2 mutations were found in nearly 30% of sporadic PKC patients.

Aprotinin inhibits the activity of several proteolytic enzymes such as chymotrypsin, kallikrein, plasmin and trypsin. Aprotinin is present in blood and in most tissues, with a high concentration in lung. Aprotinin inhibits pro-inflammatory cytokine release and maintains glycoprotein homeostasis. In platelets, aprotinin reduces glycoprotein loss (e.g., GpIb, GpIIb/IIIa), while in granulocytes it prevents the expression of pro-inflammatory adhesive glycoproteins (e.g., CD11b).

Sprouty Homolog 4 (SPRY4) is an inhibitor of the receptor-transduced mitogen-activated protein kinase (MAPK) signaling pathway. SPRY4 is positioned upstream of RAS activation. SPRY4 protein functions include suppressing the EGFR-transduced MAPK signaling pathway as well as impairing the formation of GTP-Ras.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

Speckle-type POZ protein (SPOP) belongs to the Tdpoz family containing one N-terminal MATH (Meprin and TRAF homology) domain and one C-terminal BTB/POZ domain. SPOP inhibits IPF1/PDX1 transactivation of established target promoters, may be by recruiting a repressor complex. SPOP is involved in ubiquitinylation and protein degradation as a result of an interaction with CUL-3.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

Collagen, a major component of the extracellular matrix, is a fibrous protein that provides tensile strength to tissues giving them structural integrity. Collagen and its derivative, gelatin, have been widely used in medical, pharmaceutical and consumer products for more than 100 years. The supply of these materials, created from animal remains, is both abundant and inexpensive. However, most formulations are not highly purified and have the potential to cause an inflammatory reaction in some product users. In addition, concerns have been raised over the last several years about the potential for contamination of bovine products with the agent that causes mad cow disease and its human variant, Creutzfeldt-Jakob Disease. Animal collagens are subject to extensive modifications that continue over the life of the molecule in the extracellular space. These differences influence both the extractability of collagens from tissue and the biophysical characteristics of these collagens. As a result, collagens isolated from tissues exhibit significant lot-to-lot variability and, as bulk materials, are often analytically intractable. Products that contain animal-derived collagen can induce potentially harmful inflammatory or immune responses in humans and pose risk of contamination with viruses or prions, potentially life-threatening pathogens. Recombinant collagens are essentially identical to the native collagen protein thereby reducing the risk of inflammation, immune response, and disease as compared to animal-sourced collagen.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

The recombinant Protein A/G/L is a genetically engineered protein which combines the IgG binding profiles of all Protein A, Protein G and Protein L. Protein A/G/L is a gene fusion product. Recombinant fusion protein A/G/L is comprised of 5 Ig-binding regions of protein L (B1-B2-B3-B4-B5), 5 IgG binding domains from Protein A (E-D-A-B-C) and 2 Ig-binding region of protein G (C1-C3). The recombinant Protein A/G/L is ideal for purification of monoclonal or polyclonal IgG antibodies. Protein A/G/L binds to IgG from humans, mice, rats, cows, goats, sheep, rabbits, guinea pigs, pigs, dogs and cats.

SRP54 is a 54-kDa subunit of the signal recognition particle (SRP), a cytoplasmic ribonucleoprotein complex which leads the translocation of newly synthesized secretory proteins from the polysome to the endoplasmic reticulum. SRP is composed of six polypeptides and a tRNA-like molecule known as 7SL RNA. SRP54 is a GTP-binding protein that directly binds the signal sequences of nascent secretory and membrane proteins. Anti-SRP autoantibodies take place in patients with an autoimmune chronic muscle inflammation called polymyositis. These auto-antibodies predominantly recognize the SRP54 subunit and in addition are able to immunoprecipitate several of the SRP subunits and the RNA component. Nearly 5% of myositis patients are positive for anti-SRP autoantibodies, increasing to 18% in the subgroup of Jo-1 autoantibody-negative patients. The classic 'anti-SRP syndrome' is a severe form of polymyositis in which the myositic inflammation is acute and aggressive onset, with common myalgias and cardiac involvement. Normally there is a poor reaction to therapy with a 5-year survival rate of about 25%.

Troponin is a fundamental regulatory protein of striated muscle contraction, and together with tropomyosin, is positioned on the actin filament. Troponin has 3 subunits: TnI- the inhibitor of actomyosin ATPase; TnT- contains the binding site for tropomyosin; and TnC- the protein encoded by the TNNC1 gene. The binding of calcium to TnC stops the inhibitory action of TnI, consequently allowing the interaction of actin with myosin, the hydrolysis of ATP, and the generation of tension. Mutations in the TNNC1 gene are linked to cardiomyopathy dilated type 1Z.

The PARK7 is a ubiquitously expressed protein involved in various cellular processes including spermatogenesis and fertilization, cancer, RNA-binding, androgen-receptor signaling and oxidative stress. Mutations in the PARK7 are the cause of autosomal recessive early-onset Parkinson’s disease 7 (Park7).

SKP is a 17kDa trimeric periplasmic chaperone that supports outer membrane proteins in their folding and insertion into membranes. SKP protein is necessary for the normal release of ompA from the inner membrane, the maintenance of its solubility in the periplasm, and, in association with lipopolysaccharide (LPS), for the efficient folding and insertion of ompA into the outer membrane.