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AK1 is a small ubiquitous enzyme which is essential for maintenance and cell growth. It is involved in the regulation of adenine nucleotide composition within a cell by catalyzing the reversible transfer of the terminal phosphate group between ATP and AMP. The AK1 protein is found in the cytosol of skeletal muscle, brain and erythrocytes. Defects in the AK1 gene are the cause of a form of hemolytic anemia.

Akt1, also known as Akt or else protein kinase B (PKB) is an important molecule in mammaliancellular signaling. In humans, there are three genes in the "Akt family": Akt1, Akt2, and Akt3. Moreover, these enzymes are members of the serine/threonine-specific protein kinase family (EC2.7.11.1). Akt1 is involved in cellular survival pathways, by inhibiting apoptoticprocesses. Akt1 is also able to induce protein synthesis pathways, and is therefore a key signaling protein in the cellular pathways which lead to skeletal muscle hypertrophy, and general tissue growth. Since it can block apoptosis, and thereby promote cell survival, Akt1 has been implicated as a most important factor in numerous types of cancer. Akt (now also called Akt1) was at first identified as the oncogenein the transforming retrovirus, AKT8.

Aldolase A (ALDOA) is a glycolytic enzyme, which catalyzes the reversible conversion of fructose-1,6-bisphosphate to glyceraldehyde 3-phosphate and dihydroxyacetone phosphate. ALDOA is found in the developing embryo and is produced in even greater amounts in adult muscle. ALDOA expression is repressed in the adult liver, kidney and intestine and similar to ALDOC levels in the brain and other nervous tissue. ALDOA deficiency has been linked with myopathy and hemolytic anemia.

SNTA1 is a member of the syntrophin gene family. SNTA1 is a peripheral membrane protein found linked with dystrophin and dystrophin-related proteins. Dystrophin is a large, rod-like cytoskeletal protein located at the inner surface of muscle fibers. Dystrophin is absent in Duchenne Muscular Dystrophy patients, however it is present in reduced amounts in Becker Muscular Dystrophy patients. Syntrophins are cytoplasmic peripheral membrane scaffold proteins and components of the dystrophin-associated protein complex. The N-terminal PDZ domain of SNTA1 interacts with the C-terminus of the pore-forming alpha subunit (SCN5A) of the cardiac sodium channel Nav1.5. In addition, SNTA1 associates cardiac sodium channels with the nitric oxide synthase-PMCA4b (plasma membrane Ca-ATPase subtype 4b) complex in cardiomyocytes. The SNTA1 gene is a predisposition locus for Long-QT syndrome (LQT) - an inherited disorder associated with sudden cardiac death from arrhythmia - and sudden infant death syndrome (SIDS). SNTA1 also associates with dystrophin and dystrophin-related proteins at the neuromuscular junction and modifies intracellular calcium ion levels in muscle tissue.

Trypsin (EC3.4.21.4) is part of the serine protease family. Trypsin cleaves lysine and arginine at the C-terminal side of the peptide. The hydrolysis rate is slower if an acidic residue is on either sides of the cleavage site and no cleavage occurs if a proline residue is on the carboxyl side of the cleavage site. Trypsin optimum pH is pH-7 to 9. Trypsin will also hydrolyze ester and amide linkages of synthetic derivatives of amino acids such as: benzoyl L-arginine ethyl ester (BAEE), p-toluenesulfonyl- L-arginine methyl ester (TAME), tosyl-L-arginine methyl ester, N-α-benzoyl-L-arginine p-nitroanilide (BAPNA), L-lysyl-p-nitroanilide, and benzoyl-L-tyrosine ethyl ester (BTEE). Serine protease inhibitors that inhibit recombinant trypsin include TLCK (N-p-tosyl-L-lysine chloromethyl ketone), PMSF (phenylmethanesulfonyl fluoride), benzamidine, soybean trypsin inhibitor, and ovomucoid.

Protein Phosphatase 1D (PPM1D) belongs to the PP2C family of Ser/Thr protein phosphatases whose members are negative regulators of cell stress response pathways. PPM1D is induced by tumor suppressor protein TP53/p53 in response to multiple environmental stresses. PPM1D is a negative regulator of the activity of p38 MAP kinase through which it reduces the phosphorylation of p53 and suppresses p53-mediated transcription and apoptosis. PPM1D is located in a chromosomal area which enlarges in breast cancer.

Protein Phosphatase 1, Regulatory Subunit 8 (PPP1R8) is the RNA-binding subunit of a key species of protein phosphatase-1 in the nucleus. The PPP1R8 enzyme is an inhibitor subunit of the main nuclear protein phosphatase-1 (PP-1). PPP1R8 has RNA-binding activity however it doesn’t cleave RNA and may target PP-1 to RNA-associated substrates. Two isoforms of the PPP1R8 protein are specific inhibitors of type 1 serine/threonine protein phosphatases which can bind but not cleave RNA. The third isoform of the PPP1R8 protein is deficient in of the phosphatase inhibitory activity nonetheless it is a single-strand endoribonuclease comparable to RNase E of E. coli.

Treponema pallidum is a gram-negative spirochaete bacterium and is considered to be metabolically crippled. There are at least four known subspecies: T. pallidum pallidum, T. pallidum pertenue, T. pallidum carateum and T. pallidum endemicum. The helical structure of T. pallidum pallidum allows it to move in a corkscrew motion through viscous mediums such as mucus. Treponema pallidum sub sp. pallidum has one of the smallest bacterial genomes at 1.14 million base pairs (Mb) and has limited metabolic capabilities, reflecting its adaptation through genome reduction to the rich environment of mammalian tissue.

PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and accelerate the folding of proteins. Cyclophilin-A is a cyclosporin binding-protein and may play a role in cyclosporin A-mediated immunosuppression. Cyclophilin-A can also interact with several HIV proteins, including p55 gag, Vpr, and capsid protein, and has been shown to be necessary for the formation of infectious HIV virions. Multiple pseudogenes that map to different chromosomes have been reported.

Methionine sulfoxide reductase A (MSRA) is a member of the MsrA Met sulfoxide reductase family. The MSRA enzyme has a vital function as a repair enzyme for proteins which have been inactivated by oxidation. MSRA catalyzes the reversible oxidation-reduction of methionine sulfoxide in proteins to methionine. The three substrates of the MSRA enzyme are peptide-L-methionine, thioredoxin disulfide, and H2O, while its 2 products are peptide-L-methionine (R)-S-oxide and thioredoxin. The MSRA protein is ubiquitous and extremely conserved. Human and animal studies have shown the ultimate levels of expression in kidney and nervous tissue.

Chemokine (C-X-C motif) ligand (CXCL7) is a small cytokine belonging to the CXC chemokine family. It is a protein that is released in large amounts from platelets following their activation. It stimulates various processes including mitogenesis, synthesis of extracellular matrix, glucose metabolism and synthesis of plasminogen activator.

Cysteine protease ATG4B (ATG4B) belongs to the autophagin protein family. Autophagy is the manner by which endogenous proteins and damaged organelles are destroyed intracellularly. Autophagy is vital for cell homeostasis and cell remodeling during differentiation, metamorphosis, non-apoptotic cell death, and aging. ATG4B is a cysteine protease necessary for autophagy, which cleaves the C-terminal part of either MAP1LC3, GABARAPL2 or GABARAP, allowing the liberation of form I. A subpopulation of form I is then transformed to a smaller form (form II). Form II, with an exposed C-terminal glycine, is deemed to be the phosphatidylethanolamine (PE)-conjugated form, and is capable of binding to autophagosomes. Reduced levels of autophagy are seen in some malignant tumors; therefore autophagy may have a role in controlling the unregulated cell growth linked to cancer.

PTGES2 is a membrane-associated prostaglandin E synthase, which catalyzes the conversion of prostaglandin H2 to prostaglandin E2. Additionally, PTGES2 activates the transcription regulated by a gamma-INF-activated transcription element. PTGES2 is widely expressed- in the heart, including apex, inter-ventricular septum, both atria and ventricles, but not in the aorta. PTGES2 is also expressed in fetal heart. PTGES2 is detected in various regions of the brain: cerebellum; occipital, frontal and parietal lobes. It is also expressed in the lymph nodes, skeletal muscle, kidney and trachea, but not in the thymus or lung. PTGES2 is overexpressed in colorectal cancer.

GSTM3 belongs to the glutathione s-transferase (GST) family of proteins. There are eight GST proteins families, named alpha, kappa, mu, omega, pi, sigma, theta and zeta. Each one of the GST families has several proteins with different functions throughout the cell. The mu type of enzymes takes part in the detoxification of electrophilic compounds, including therapeutic drugs, carcinogens, environmental toxins and products of oxidative stress, by conjugation with glutathione.

XIAP Associated Factor 1 (XAF1) is a protein which binds to and counteracts the inhibitory effect of a member of the IAP (inhibitor of apoptosis) protein family. IAP proteins bind to and inhibit caspases which are activated in the course of apoptosis. The ratio of IAPs and proteins which interfere with their activity, such as the XAF1 protein, influence the progress of the apoptosis signaling pathway. Additionally, XAF1 inhibits anti-caspase activity of BIRC4. XAF1 induces cleavage and inactivation of BIRC4 independent of caspase activation. Furthermore, XAF1 mediates TNF-alpha-induced apoptosis and is involved in apoptosis in trophoblast cells.

RND3 is a small GTPase which is part of the Ras superfamily that controls the association of the actin cytoskeleton in reaction to extracellular growth factors. RND3 activity causes a decrease in stress fibers and an increase in cell migration, at least in part through regulation of the Rho-dependent kinase ROCK1. RND3 inhibits DNA-damage induced apoptosis and cell cycle arrest. RND3 binds GTP and is resistant to Rho-specific GTPase-activating proteins.

Iduronate 2-Sulfatase also known as IDS, belongs to the highly-conserved sulfatase family of enzymes which catalyze the hydrolysis of O-sulfate and N-salfate esters from a variety of substrates. IDS is essential for the lysosomal degradation of the glycosaminoglycans (GAG) heparan sulfate as well as dermatan sulfate. Furthermore, IDS hydrolyzes the 2-sulfate group of the IDS units of the GAG.

EPH Receptor A2 (EPHA2) is a member of the ephrin receptor subfamily of the protein-tyrosine kinase family. EPHA2 is a protein which binds ephrin-A ligands. EPH and EPH-related receptors are associated with mediating developmental events, particularly in the nervous system. Receptors in the EPH subfamily normally have a single kinase domain and an extracellular region containing a Cys-rich domain and 2 fibronectin type III repeats. The ephrin receptors are divided into two groups based on the similarity of their extracellular domain sequences and their affinities for binding ephrin-A and ephrin-B ligands. EPHA2 gene mutations are the cause of certain genetically-related cataract disorders.

PPA1 is a member of the PPase family. PPA1 catalyzes the conversion of one molecule of pyrophosphate to two phosphate ions. Many biochemical pathways use the hydrolysis of PPi to two phosphate ions to make the reactions permanently irreversible. A prominent illustration of this phenomenon is the inorganic pyrophosphatase catalyzation in the hydrolysis reaction at the beginning of lipid degradation. Inorganic pyrophosphatase provides the motivation for the activation of fatty acids destined for oxidation by stimulating the rapid hydrolysis of pyrophosphate.

Human Phosphoserine phosphatase (hPSP) is an important enzyme in the phosphorylated pathway of serine biosynthesis, which contributes a major portion of the endogenous L-serine. Similar to known L-3-phosphoserine phosphatases, it catalyzed the Mg2+-dependent hydrolysis of L-phosphoserine and an exchange reaction between L-serine and L-phosphoserine. Recently, its complex structures reveal that the open-closed environmental change of the active site, generated -helical bundle domain, is important to substrate by local rearrangement of the recognition and hydrolysis.

Cathepsin-Z (CTSZ) is a lysosomal cysteine proteinase and a member of the peptidase C1 family. CTSZ, which is known also as cathepsin X and cathepsin P, exhibits carboxy-monopeptidase and carboxy-dipeptidase activities. CTSZ is expressed ubiquitously in cancer cell lines and primary tumors and as other members of this family, takes part in tumorigenesis.

Pyruvate Dehydrogenase Complex, Component X, also known as PDHX, encodes the E3 binding protein subunit of the PDH complex which contains 3 catalytic subunits. PDHX tethers E3 dimers to the E2 core of the pyruvate dehydrogenase complexes of eukaryotes. This specific binding is critical for a functional PDH complex.

NANS is a 359 amino acid protein that contains one AFP (antifreeze proteins)-like domain and functions in the biosynthesis of sialic acids. The ubiquitously expressed NANS enzymatically catalyzes the H2O-dependent formation of N-acetylneuraminic acid (Neu5Ac) and 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN), both of which are sialic acids. NANS uses N-acetylmannosamine 6-phosphate as a substrate for Neu5Ac synthesis and mannose 6-phosphate as a substrate for KDN synthesis.