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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.

HSPA9 is part of the heat shock protein 70 family which contains both heat-inducible and constitutively expressed members that are also called heat-shock cognate proteins. HSPA9 encodes a heat-shock cognate protein that is involved in the control of cell proliferation and acts as a chaperone. HSPA9 was restricted to chromosome 5, band q31, a region that is often deleted in myeloid leukemias and myelodysplasia (MDS), making it a candidate tumor suppressor gene, which is consistent with the biological function of its murine homologue. HSPA9 supresses nuclear translocation, transcriptional activation, and control of centrosome-duplication functions of p53.

FIS1 is part of the mitochondrial complex that promotes mitochondrial fission. FIS1 induces cytochrome C discharge from the mitochondrion to the cytosol, eventually leading to apoptosis. FIS1 participates in peroxisomal growth and division. The C terminus is required for mitochondrial localisation, while the N teminus is necessary for mitochondrial fission.

Human immunodeficiency virus type-1 (HIV-1) regulatory Tat protein plays an essential role in viral replication and infectivity. The HIV-1 TAT is a molecule of 86 aminoacids encoded by two exons. The product of the first exon is sufficient for the transactivation of the HIV-1 promoter. Biotin molecules can be coupled easily to either antigens (such as avidin, streptavidin, Fc binding proteins like Protein A or G) or antibodies and they can be used in a variety of detection systems.
Biotin can be conjugated to many proteins without significantly changing their biological activity. Biotin binds with high affinity to avidin, streptavidin and NeutrAvidin protein.
Every single protein can react with several molecules of biotin, each of which, in turn, can bind a molecule of avidin. This greatly increases the sensitivity of many assay procedures. The avidin-biotin interaction is the strongest known noncovalent biological interaction (Ka = 1015 M-1) between protein and ligand. The bound formation between biotin and avidin is very rapid and, once formed, withstands extremes of pH, organic solvents and other denaturing agents. The avidinbiotin complex can withstand up to 3 M guanidine•HCl. Biotin can be released by 8 M guanidine•HCl at pH 1.5, or by autoclaving.

Pleiotrophin (Osteoblast-Specific Factor-1, OSF-1) contains 136 amino acid residues. The sequence is very rich in cationic amino acids (24% of the residues); lysine cluster sequences are found in the N-terminal and C-terminal ends of the structure.
The OSF-1 gene was shown by Northern blotting analysis to be expressed in mouse calvarial osteoblast-enriched cells and in mouse brain tissues, but not in thymus, spleen, kidney, liver, lung, testis or heart. Pleiotrophin has the ability to promote adhesion, migration, expansion, and differentiation of human osteoprogenitor cells. In addition to certain types of cancer, the embryonic growth and differentiation factor pleiotrophin is found also in adults in inflammatory diseases. In osteoarthritis, pleiotrophin is especially expressed in early stages, and its concentrations in the synovial fluid could serve as a marker for the progress of the disease. Pleitrophin might be involved in cartilage repair in osteoarthritis, in particular, in earlier stages.

Syntaxin is membrane integrated Q-SNARE protein participating in exocytosis. Syntaxin is composed of an N-terminal regulatory domain (Habc), a SNARE domain (known as H3), and a single C-terminal transmembrane domain. The SNARE (H3) domain binds to both synaptobrevin and SNAP-25 forming the core SNARE complex. Synaptic vesicles store neurotransmitters that are released during calcium-regulated exocytosis. The specificity of neurotransmitter release requires the localization of both synaptic vesicles and calcium channels to the presynaptic active zone. Syntaxins function in this vesicle fusion process. Syntaxins also serve as a substrate for botulinum neurotoxin type C, a metalloprotease that blocks exocytosis and has high affinity for a molecular complex that includes the alpha-latrotoxin receptor which produces exocytosis.

Myoglobin is a member of the globin superfamily and can be found in skeletal and cardiac muscles. It is a haemoprotein that contributs to intracellular oxygen storage and transcellular facilitated diffusion of oxygen. Myoglobin has a single-chain globular structure of 153 amino acids, containing a heme prosthetic group (iron-containing porphyrin) in the core around which the remaining apoprotein folds. Myoglobin has 8 alpha helices and a hydrophobic core. Myoglobin’s molecular weight is 16.7 kDa, and it is the primary oxygen-carrying pigment of muscle tissues. The binding of oxygen in myoglobin is different from the cooperative oxygen binding in hemoglobin, since positive collaboration is a property of multimeric/oligomeric proteins only. Instead, the binding of oxygen by myoglobin is uninfluenced by the oxygen pressure in the surrounding tissue. Myoglobin is frequently referred to as having an "instant binding tenacity" to oxygen given its hyperbolic oxygen dissociation curve. Different organisms are able to hold their breaths longer due to high concentrations of myoglobin in their muscle cells. Myoglobin is responsible for the pigments that make meat red. The color of the meat is partly determined by the charge of the iron atom in myoglobin and the oxygen attached to it. Myoglobin is found in Type I muscle, Type II A and Type II B, but it is mostly deemed that myoglobin is not found in smooth muscle. Myoglobin is discharged from damaged muscle tissue (rhabdomyolysis), which contains very high concentrations of myoglobin. Even though the released myoglobin is filtered by the kidneys, it is toxic to the renal tubular epithelium and thus may cause acute renal failure.

Thyrotroph embryonic factor (TEF) is a nuclear transcription factor which is a part of the bZIP (basic region/leucine zipper) family and PAR subfamily. TEF binds DNA as either a homodimer or heterodimer, and is known to transactivate the TSH beta promoter. TEF accumulates according to a robust circadian rhythm and is also inhibits cell growth by down-regulating beta chain expression of cytokine receptors.

The Trefoil Factor peptides (TFF1, TFF2 and TFF3) are stable secretory proteins expressed in the gastrointestinal tract (gastric mucosa), and are involved in intestinal mucosal defense and repair. TFF1 is an essential protein for normal differentiation of the antral and pyloric gastric mucosa and functions as a gastric-specific tumor suppressor gene. TFF1 is a stabilizer of the mucous gel overlying the gastrointestinal mucosa that provides a physical barrier against various noxious agents. TFF1 protects the mucosa from isults, stabilizes the mucus layer, & affects healing of the epithelium. TFF1 is commonly expressed in tumors. TFF1 is related with the cell membrane of MCF-7 cells. High levels of TFF1 and TFF2 are found in serum from inflammatory bowel disease.

Mediator complex subunit 4 (MED4) is a component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. MED4 is a component of the vitamin D receptor-interacting protein (DRIP) complex which functions as a nuclear receptor coactivator. The DRIP complex is able to activate nuclear receptors in a ligand-dependent manner. MED4 functions as a link to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription apparatus. MED4 is recruited to promoters by direct interactions with regulatory proteins and serves as a scaffold for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors.

Secretoglobin Family 1D, Member 1 (SCGB1D1) belongs to the lipophilin subfamily, part of the uteroglobin superfamily, and is an ortholog of prostatein (which is the major secretory glycoprotein of the rat ventral prostate gland). SCGB1D1 binds androgens and other steroids. In addition SCGB1D1 binds chemotherapeutic drugs during the prostate cancer treatment. Steroid hormones regulate the SCGB1D1 transcription. SCGB1D1 is secreted into extracellular space. SCGB1D1 gene product represents one component of a heterodimeric molecule found in human tears whose elution profile is consistent with prostatein (which is a tetrameric molecule comprised of 3 peptide components in heterodimers).

Methionine sulfoxide reductase B1 (SEPX1 or MSRB1), is a selenoprotein that contains a selenocysteine (Sec) residue at its active site. The selenocysteine is encoded by the UGA codon that usually signals translation termination. SEPX1 is a member of the methionine sulfoxide reductase B (MsrB) family, and is expressed in an assortment of adult and fetal tissues. MSRs (Methionine sulfoxide reductases) catalyze the reduction of free and protein-bound methionine sulfoxides to corresponding methionines. The oxidation of methionine by ROS creates a diastereomeric mixture of methionine-S-sulfoxide (Met-S-SO) and methionine-R-sulfoxide (Met-R-SO). Two separate enzyme families evolved for reduction of these sulfoxides, with methionine-S-sulfoxide reductase (MsrA) being stereospecific for Met-S-SO and methionine-R-sulfoxide reductase (MsrB) for Met-R-SO.

SPINT2 is a transmembrane protein acts as an inhibitor of HGF activator. SPINT2 inhibits plasmin, plasma and tissue kallikrein, and factor XIa. SPINT2 has two extracellular Kunitz domains that inhibit few serine proteases. SPINT2 is assumed tumor suppressor, mutations in SPINT2 leads to a congenital sodium diarrhea.

HCV is a small 50nm, enveloped, single-stranded, positive sense RNAvirus in the family Flaviviridae.
HCV has a high rate of replication with approximately one trillion particles produced each day in an infected individual. Due to lack of proofreading by the HCV RNA polymerase, the HCV has an exceptionally high mutation rate, a factor that may help it elude the host's immune response. Hepatitis C virus is classified into six genotypes(1-6) with several subtypes within each genotype. The preponderance and distribution of HCV genotypes varies globally. Genotype is clinically important in determining potential response to interferon-based therapy and the required duration of such therapy. Genotypes 1 and 4 are less responsive to interferon-based treatment than are the other genotypes (2, 3, 5 and 6).

Plasma protease C1 inhibitor (SERPING1) is a part of the serpin superfamily of serine protease inhibitors. SERPING1 plays an important role in regulating activation of both the complement and contact systems. That isdue to the fact that SERPING1 regulates the activation of complement factor C1 in addition to the activity of activated C1 by coupling with the active catalytic site at the light chains of C1r and C1s. SERPING1 insufficiency results in hereditary angioedema, which is characterized by recurrent episodes of localized angioedema of the skin, gastrointestinal mucosa or upper respiratory mucosa.

C8, a component of the complement system consists of three polypeptides C8A, C8B and C8G and takes part in the formation of Membrane Attack Complex (MAC). Patients with C8 deficiency are exposed to several bacteria infections. C8G, a member of the lipocalin family and calycin superfamily, is a secreted protein that can bind retinol. C8G is created in the liver, monocytes and fibroblast and has a role in clearing pathogens from an infected host.

GTF2B is one of the ubiquitous factors needed for transcription initiation by RNA polymerase II preinitiation factor. GTF2B localizes to the nucleus where it forms a complex (the DAB complex) with transcription factors IID and IIA. GTF2 plays a role as a bridge between IID, which initially recognizes the promoter sequence, and RNA polymerase II. GTF2B is involved in the selection of the transcription start site.

The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms, β, γ, ε, σ, ζ, τ and η that have been identified in mammals. The 14-3-3 epsilon, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with CDC25 phosphatases, RAF1 and IRS1 proteins, suggesting its role in diverse biochemical activities related to signal transduction, such as cell division and regulation of sensitivity. It has also been implicated in the pathogenesis of small cell lung cancer.

Prefoldin subunit 2 (PFDN2) belongs to the prefoldin beta subunit family. The PFDN2 protein is one of 6 subunits of prefoldin, which is a molecular chaperone complex that binds and stabilizes newly synthesized polypeptides, thus allowing them to fold correctly. PFDN2 binds specifically to cytosolic chaperonin (c-CPN) and transfers target proteins to it. PFDN2 also binds to a nascent polypeptide chain and promotes folding in an setting in which there are many competing pathways for nonnative proteins.

TFPI is a protease inhibitor which controls the tissue factor (TF)-dependent pathway of blood coagulation. The coagulation process starts with the creation of a factor VIIa-TF complex, that proteolytically triggers additional proteases (factors IX and X) and eventually results in a fibrin clot. TFPI inhibits the activated factor X and VIIa-TF proteases in an autoregulatory loop. TFPI is glycosylated and predominantly located in the vascular endothelium and plasma in both free forms and complexed with plasma lipoproteins. A number of alternatively spliced transcript variants of this gene have are known, however the full-length nature of several of these variants were not yet established.

STMN2 is a neuronal growth-associated protein which shares a majority of its amino acid sequence with the phosphoprotein stathmin. STMN2 is involved in neuronal differentiation and in modulating membrane interaction with the cytoskeleton through neurite outgrowth. STMN2 is necessary for maintaining the anchorage-independent growth state of beta-catenin/TCF-activated hepatoma cells. SCG10 is a novel indicator of osteogenesis and osteoblast that takes part in the regulation of the adipocyte/osteoblast balance. STMN2 plays a role as an effector downstream of Rnd1 to regulate axon extensions by modulating microtubule organization.

U2 small nuclear ribonucleoprotein A (SNRPA1), a 255 amino acid protein, is a component of the U2 snRNP which forms a complex with U2 snRNP B (U2B). U2 snRNP A and U2 snRNP B form together a complex which binds to the U2 snRNA hairpin IV. The configuration of the U2 snRNP A/U2 snRNP B dimer and the delicate variations of a few key residues regulate the snRNP-RNA-binding specificity.

ESM1, also knows as, Endothelial cell-specific molecule 1 is a protein encoded by a gene called ESM1 in humans. ESM1 is a secreted protein that is highly expressed in human kidney and lung tissues (in the endothelial cells). There are suggestions regarding the protein’s involvement in endothelium-dependent pathological diseases, due to his regulation that is performed by cytokines.