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Trypsin is a serine protease that hydrolyses proteins, it is found in the digestive system of numerous vertebrates. Trypsin is produced as the inactive proenzyme trypsinogen in the pancreas. Trypsin cleaves peptide chains at the carboxyl side of the amino acids lysine and arginine, except when either is followed by proline. Trypsin is secreted into the duodenum, where it acts to hydrolyses peptides into amino acids, which is necessary for the uptake of protein in the food even though peptides are smaller than proteins; they are still too big to be absorbed through the lining of the ileum. The optimal operating pH for Trypsins is about 8 and about 37°C temperature. In cystic fibrosis disease there is a deficiency in transport of trypsin and other digestive enzymes from the pancreas. Trypsin is widely used in various biotechnological processes since it’s available in high quantity in the pancreases, and can be purified rather easily.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is wilyde 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.

Tropomyosin alpha-3 chain (TPM3) belongs to the tropomyosin family of actin-binding proteins involved in the contractile system of striated and smooth muscles and the cytoskeleton of non-muscle cells. Tropomyosins are dimers of coiled-coil proteins which polymerize end-to-end along the major groove in most actin filaments. Tropomyosins give stability to the filaments and regulate access of other actin-binding proteins. In muscle cells, tropomyosins regulate muscle contraction by controlling the binding of myosin heads to the actin filament. Mutations in the TPM3 gene cause autosomal dominant nemaline myopathy, and oncogenes formed by chromosomal translocations involving this locus are linked with cancer.

TSG101 is a member of apparently inactive homologs of ubiquitin-conjugating enzymes. TSG101 contains a coiled-coil domain that interacts with stathmin, a cytosolic phosphoprotein implicated in tumorigenesis. TSG101 is involved in cell growth and differentiation and acts as a negative growth regulator. TSG101 in vitro steady-state expression is important for maintenance of genomic stability and cell cycle regulation. TSG101 mutations and alternative splicing occur in high rate in breast cancer and implicate that defects occur during breast cancer tumorigenesis and/or progression. TSG101 is a factor of the ESCRT-I complex, a monitor of vesicular trafficking process. TSG101 binds to ubiquitinated cargo proteins and is needed for the sorting of endocytic ubiquitinated cargos into multivesicular bodies. TSG101 is needed for completion of cytokinesis and is involved in cell growth and differentiation.

PTX-2 or Pentraxin-2 is a phylogenetically conserved protein, commonly moving with homopentameric blood protein or with a protein that recognizes receptors of the innate immune system. The protein’s specific binding abilities may show that PTX-2 is specially bound in sites where injury accrued, therefore helps to eliminate damaged tissue by ways that are not phlogistics.

SRGN is identified as a hematopoietic cell granule proteoglycan. Proteoglycans stored in the secretory granules of various hematopoietic cells also hold a protease-resistant peptide core, and is vital for neutralizing hydrolytic enzymes. SRGN is related to the macromolecular complex of granzymes and perforin that acts as a intermediary of granule-mediated apoptosis.

The signal sequence receptor (SSR) is a glycosylated endoplasmic reticulum membrane receptor related with protein translocation across the ER membrane. The SSR consists of 2 subunits, a 34-kD glycoprotein (alpha-SSR or SSR1) and a 22-kD glycoprotein (beta-SSR or SSR2). The human beta-signal sequence receptor gene (SSR2) maps to chromosome bands 1q21-q23. Diseases correlated with SSR2 include calcaneonavicular coalition, and osteosarcoma, and among its related super-pathways are Viral mRNA Translation and Generic Transcription Pathway.

TCL1A (T-cell leukemia/lymphoma 1A) is a protein with a possible role in intracellular regulation of T cell signaling. TCL1A enhances cell proliferation, stabilizes mitochondrial membrane potential and promotes cell survival. TCL1A is restricted in the T-cell lineage to immature thymocytes and activated peripheral lymphocytes. TCL1A is preferentially expressed early in T and B-lymphocyte differentiation. Chromosomal anomalies activating TCL1A are found in chronic T-cell leukemias (T-CLL).
TCL1A enhances the phosphorylation and activation of AKT1, AKT2 and AKT3. TCL1A promotes nuclear translocation of AKT1. TCL1A binds to the pleckstrin homology domain of Akt (protein kinase B) family proteins, which facilitates Akt dimerization and activity. By increasing Akt activity, TCL1A can enhance the serine/threonine phosphorylation of major Akt signaling substrates, for example Ikk complex, mTOR, BAD, p70S6 kinase, FOXO transcription factors and GSK3b. These substrates regulate cellular differentiation, growth, survival, and metabolism.

IGFBP1 is a member of the insulin-like growth factor binding protein (IGFBP) family and encodes a protein with an IGFBP domain and a thyroglobulin type-I domain. The protein binds both insulin-like growth factors (IGFs) I and II and circulates in the plasma. Binding of this protein prolongs the half-life of the IGFs and alters their interaction with cell surface receptors. Alternate transcriptional splice variants, encoding different isoforms, have been characterized.

CTSW protein belongs to the peptidase C1 family. CTSW is a cysteine proteinase with a detailed role in the regulation and mechanism of T-cell cytolytic activity. The encoded CTSW is linked to the membrane inside the endoplasmic reticulum of natural killer and cytotoxic T-cells. CTSW expression is up-regulated by interleukin-2.

Tyrosine 3-monooxygenase (Th), is a rate-limiting enzyme in catecholamine synthesis. Th utilizes tetrahydrobiopterin as well as molecular oxygen to convert tyrosine to DOPA. Th regulates dopamine (DA) neurotransmission at the biosynthesis and reuptake steps. Th takes a vital part in the physiology of adrenergic neurons. Furthermore, Th effects overexpression in lymphocytes on the differentiation as well as function of T helper cells.

PTHrP is a powerful and discriminating agonist of PTH2R which takes part in adenyl cyclase activation and intracellular calcium levels elevation. PTHrP encourages protein kinase C beta activation, recruitment of beta-arrestin and PTH2R internalization. Additionally, PTHrP inhibits cell proliferation through its contribution to PTH2R activation, activates nociceptors and nociceptive circuits and acts as a neuropeptide in spermatogenesis.

P-Selectin also called Platelet Alpha-Granule Membrane Protein, CD62, and Granulocyte Membrane Protein GRMP belongs to a family of divalent cation-dependent carbohydrate-binding glycoproteins or adhesion molecules. Pselectin is expressed transiently on the surface of activated platelets and endothelial cells. P-Selectin is a 140 kDa protein which is stored in the alpha-granules of platelets and Weibel-Palade bodies of endothelial cells. Secreted P-selectin is thought to play a key role in the adhesion of platelets to monocytes and neutrophils during an inflammatory response. P-Selectin is a calcium-dependent receptor that binds to sialylated forms of Lewis blood group carbohydrate antigens on neutrophils and monocytes. Levels of P-Selectin may be elevated in a number of pathological conditions.

Celiac disease is an enteropathy that is characterized by intestinal lesions of variable severity. Tissue-type transglutaminase (tTG) is believed to be the predominant autoantigen for celiac disease and the corresponding autoantibodies show higher sensitivity and specificity than anti-gliadin antibodies. Highly pure recombinant human tTG is now available to replace the traditionally used tTG fraction from guinea pig.
Tissue-type transglutaminase antigens have been specifically modified for improved handling: exchange of an active site amino acid eliminates the protein cross-linking activity of the enzyme, while maintaining the native three-dimensional structure and the enzyme's secondary GTPase activity. This engineering assures reproducible properties of the antigen preparations through the absence of variable and ill-defined covalent aggregates of tTG antigen and host cell proteins.

TNNI2 is a fast-twitch skeletal muscle protein, belongs to the troponin I gene family, and is part of the troponin complex including troponin T, troponin C and troponin I subunits. The troponin complex, together with tropomyosin, is responsible for the calcium-dependent regulation of striated muscle contraction. TNNI2 is also present in vascular smooth muscle and may play a role in regulation of smooth muscle function. Other than muscle tissues, TNNI2 is found in corneal epithelium, cartilage where it is an inhibitor of angiogenesis to inhibit tumor growth and metastasis, and mammary gland where it functions as a coactivator of estrogen receptor-related receptor alpha. Furthermore, TNNI2 suppresses tumor growth in human ovarian carcinoma. Mutations in the TNNI2 gene cause myopathy and distal arthrogryposis type 2B.

Ro 60 kDa autoantigen is an RNA-binding protein that binds to several small cytoplasmic RNA molecules known as Y RNAs. SSA2 may stabilize these RNAs from degradation. Sera taken from patients with Systemic Lupus Erythematosus (SLE) often contains antibodies that react with the normal cellular SSA2 protein as if this antigen was foreign.

GRPEL1 is a vital component of the PAM complex, a complex necessary for the translocation of transit peptide-containing proteins from the inner membrane into the mitochondrial matrix in an ATP-dependent manner. GRPEL1 protein controls the nucleotide-dependent binding of mitochondrial HSP70 to substrate proteins.

Borrelia belongs to a genus of bacteria of the spirochete phylum. Borrelia causes borreliosis, which is a zoonotic, vector-borne disease transmitted mainly by ticks and some by lice, depending on the species. Of the 36 known species of Borrelia, 12 are distinguished to cause Lyme disease or borreliosis and are transmitted by ticks. The main Borrelia species causing Lyme disease are Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii. The Borrelia genus members have a linear chromosome which is about 900 kbp in length as well as an excess of both linear and circular plasmids in the 5-220 kbp size range. The plasmids are atypical, as compared to most bacterial plasmids, since they contain many paralogous sequences, a large number of pseudogenes and, in some cases, essential genes. Moreover, a number of the plasmids have features suggesting that they are prophages.

The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGF-a , betacellulin, epiregulin, heparin-binding EGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

Proprotein Convertase Subtilisin/Kexin Type 1 Inhibitor (PCSK1N) takes part in the control of the neuroendocrine secretory pathway. PCSK1N inhibits prohormone convertase 1, which regulates the proteolytic cleavage of neuroendocrine peptide precursors. PCSK1Nslows down convertase-mediated processing of proopiomelanocortin and proenkephalin and also monitors the intracellular timing of PCSK1.

TDO2 is a ferrous heme enzyme that catalyzes the first and rate-limiting step in the kynurenine pathway which is the major pathway of tryptophan metabolism. TDO2 integrates oxygen into the indole moiety of tryptophan. TDO2 has broad specificity towards tryptamine and derivatives including D- and L-tryptophan, 5-hydroxytryptophan and serotonin.

TFAM is a mitochondrial transcription factor which is a main activator of mitochondrial transcription and is also a participant in mitochondrial genome replication. TFAM is situated primarily in the nuclei of elongated spermatids and takes part in the regulation of gene expression of the haploid male genome. TFAM is linked to mitochondrial disorder in humans characterized by ocular myopathy, exercise intolerance and muscle wasting.