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ACP1 is part of the phosphotyrosine protein. ACP1 functions as an acid phosphatase and a protein tyrosine phosphatase (PTPase) existing in all human tissues, including adipocytes. ACP1 enzyme hydrolyzes protein tyrosine phosphate to protein tyrosine and orthophosphate, and also orthophosphoric monoesters to alcohol and orthophosphate. ACP1 is present in adipocytes, thus playing a specific role in the regulation of adipose tissue. High levels of the ACP1 negatively regulate cell proliferation and growth of leiomyomas during dephosphorylation of the PDGF receptor. High significant differences in birth weight-placental weight relationships were observed among acid phosphatase locus 1 phenotypes.

Poly (ADP-Ribose) Polymerase 2 (PARP2) contains a catalytic domain which is homologous to that of poly (ADP-ribosyl) transferase but lacks an N-terminal DNA binding domain which activates the C-terminal catalytic domain of poly (ADP-ribosyl) transferase. PARP2 is capable of catalyzing a poly (ADP-ribosyl)ation reaction. The basic residues within the N-terminal area of this protein can bear potential DNA-binding properties, and can be engaged in the nuclear and/or nucleolar targeting of the protein. There has been found two alternatively spliced transcript variants encoding distinct isoforms.

Cathepsins B, C, H, L, S, V, X/Z/P and 1 are cysteine proteases of the papain family. Cathepsin C is also known as DPPI (dipeptidyl-peptidase I). Cathepsin A is a serine carboxypeptidase and Cathepsin D and E are aspartic proteases. As lysosomal proteases, cathepsins play an important role in protein degradation. Because of their redistribution or increased levels in human and animal tumors, cathepsins may have a role in invasion and metastasis. Cathepsins are synthesized as inactive proenzymes and processed to become mature and active enzymes. Endogenous protein inhibitors, such as cystatins and some serpins, inhibit active enzymes.

PNMT is an enzyme located in the adrenal medulla and it catalyzes the final step of the catecholamine biosynthesis pathway, which methylates norepinephrine to form epinephrine (adrenaline). PNMT has beta-carboline 2N-methyltransferase activity. PNMT takes part in regulating epinephrine production. Glucocorticoid receptors form multimers of PNMT independent of the DNA binding domain. PNMT expression is regulated late in mouse gestation by AP2-alpha and glucocorticoids.

Carboxymethylenebutenolidase homolog (CMBL) is a cysteine hydrolase of the dienelactone hydrolase family which is highly expressed in the liver cytosol. CMBL is the human homolog of Pseudomonas dienelactone hydrolase, which is a protein that participates in the bacterial halocatechol degradation pathway. CMBL which preferentially cleaves cyclic esters activates medoxomil-ester prodrugs in which the medoxomil moiety is coupled with an oxygen atom. CMBL is inhibited by PCMB (p-chloromercuribenzoate) and is encoded by a gene which maps to human chromosome 5p15.2. Furthermore, CMBL converts the prodrug olmesartan medoxomil into its pharmacologically active metabolite olmerstatan, which is an angiotensin receptor blocker, in the liver and intestine. CMBL can also activate beta-lactam antibiotics faropenem medoxomil and lenampicillin. CMBL is widely expressed, with the highest levels in the liver, followed by the kidney, small intestine and the colon.

Matrix Metalloproteinase-13 (MMP-13) is an enzyme that is a member of the MMP extracellular protease family. Extracellular protease enzymes, by virtue of their broad substrate specificities1, play a role in both normal and disease states of tissue proliferation. Among the targets of MMP-13 are collagen, gelatin, entactin, pro-TNF-a, and chemokine SDF-11-4.
MMP-13 is found in its latent form as a 52-56 kDa glycosylated proenzyme. Upon cleavage the 22-46 kDa5 MMP-1 becomes active in extracellular matrix remodeling.
Because of the prominent role that MMP-1 plays in cell migration and metastasis, it is an important target for inhibition screening.

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.

Pyridoxine-5'-phosphate oxidase (PNPO) is the rate-limiting enzyme in vitamin B6 synthesis. Vitamin B6 (Pyridoxal 5-prime-phosphate or PLP) is vital for normal cellular function, and some cancer cells have notable differences in vitamin B6 metabolism compared to their normal counterparts.Vitamin B6 is an essential co-factor for enzymes involved in both homocysteine metabolism and synthesis of neurotransmitters such as catecholamine. Mutations in the PNPO gene result in PNPO deficiency, a form of neonatal epileptic encephalopathy.

The 26S proteasome is a multicatalytic proteinase complex with a well ordered structure composed of two complexes- a 20S core and a 19S regulator. PSMD11 is a non-ATPase subunit of the 19S regulator. The 20S core is composed of four rings of 28 non-identical subunits; two rings are composed of 7 alpha subunits and two rings are composed of 7 beta subunits. The 19S regulator is composed of a base that contains six ATPase subunits and two non-ATPase subunits, and a lid that contains up to ten non-ATPase subunits. Proteasomes are spread throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An indispensable function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides.

Isocitrate Dehydrogenase is an enzyme of the oxidoreductase class that catalyzes the conversion of isocitrate and NAD+ to yield 2-ketoglutarate, carbon dioxide, and NADH. It occurs in cell mitochondria. The enzyme requires Mg2+, Mn2+; it is activated by ADP, citrate, and Ca2+, and inhibited by NADH, NADPH, and ATP. The reaction is the key rate-limiting step of the citric acid (tricarboxylic) cycle.

Protein Phosphatase 2C alpha is a member of the PP2C family of Ser/Thr protein phosphatases. PP2C family members are known to be negative regulators of cell stress response pathways. This phosphatase dephosphorylates, and negatively regulates the activities of, MAP kinases and MAP kinase kinases. It has been shown to inhibit the activation of p38 and JNK kinase cascades induced by environmental stresses. This phosphatase can also dephosphorylate cyclin-dependent kinases, and thus may be involved in cell cycle control. Overexpression of this phosphatase is reported to activate the expression of the tumor suppressor gene TP53/p53, which leads to G2/M cell cycle arrest and apoptosis. Three alternatively spliced transcript variants encoding two distinct isoforms have been described. Protein phosphatase 2C(PP2Cα) is a Mn2+- or Mg2+-dependent protein serine/threonine phosphatase that is essential for regulating cellular stress response in eukaryotes.

Prolyl Endopeptidase , also known as PREP is a cytosolic prolyl endopeptidase which cleaves peptide bonds on the C-terminal side of prolyl residues within peptides which are up to about 30 a.a long. In addition, Prolyl endopeptidases have been shown to be implicated in the maturation and degradation of peptide hormones and neuropeptides.

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.

Adenosylmethionine decarboxylase proenzyme (AMD1) is synthesized originally as an inactive proenzyme. Putrescine stimulates both the proenzyme processing and the catalytic activity. The catalytic activity is inhibited by iodoacetic acid. The active enzyme formation entails a self-maturation process in which the active site pyruvoyl group is produced from an internal serine residue using an autocatalytic post-translational modification.

NEDD8-activating enzyme E1 regulatory subunit (NAE1) is a member of the ubiquitin-activating E1 family. NAE1 binds to the beta-amyloid precursor protein. Beta-amyloid precursor protein is a cell surface protein with signal-transducing properties, and it is believed to have a role in the pathogenesis of Alzheimer's disease. NAE1 participates in a unique ubiquitinylation-related pathway involving the ubiquitin-like molecule NEDD8. Furthermore, the NAE1 protein is essential for cell cycle progression through the S/M checkpoint.

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.

Myoglobin is a member of the globin superfamily and exists in skeletal and cardiac muscles. Myoglobin is a haemoprotein that contributs to intracellular oxygen storage and transcellular facilitated diffusion of oxygen. 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.

DBH catalyzes the chemical reaction. DBH is an oxidoreductase which belongs to the copper type II, ascorbate-dependent monooxygenase family, in particular those performing on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated can not be derived from O2 with reduced ascorbate as one donor, as well as incorporation of one ato of oxygen into the other donor.

PPM1G is part of the PP2C family of Ser/Thr protein phosphatases which are known to be negative regulators of cell stress response pathways. PPM1G is accountable for the dephosphorylation of Pre-mRNA splicing factors, an important factor for the formation of functional spliceosome. PPM1G regulates cell cycle progression. PPM1G mediates histone dephosphorylation/exchange in response to DNA damage or checkpoint recovery in higher eukaryotes. The degradation of p21/WAF1 induced by PPM1G is mediated in a proteasome-dependent manner. Protein phosphatase 1G regulates assembly and function of the beta-catenin degradation complex.

AK3L1 is an affiliate of the adenylate kinase family of enzymes. AK3L1 enzyme is restricted to the mitochondrial matrix. Adenylate kinases-3 regulates the adenine and guanine nucleotide compositions within a cell by means of catalyzing the reversible transfer of phosphate group among these nucleotides. 5 different isozymes of adenylate kinase have been identified in vertebrates. The enzyme expression of various adenylate kinase isozymes is growth regulated and tissue-specific.

DCTD is an allosteric enzyme that exists as a homohexamer and is part of the cytidine and deoxycytidylate deaminase protein family. DTCD uses zinc as a cofactor to catalyze the deamination of dCMP to dUMP, thus making the nucleotide substrate (dUMP) that is used by thymidylate synthase.

PRDX1 is part of the peroxiredoxin family of antioxidant enzymes, which reduce hydrogen peroxide and alkyl hydroperoxides. PRDX1 is an important protector of red blood cells against reactive oxygen species and in tumor prevention. PRDX1 is antioxidant protective in cells, and contributes to the antiviral activity of CD8(+) T-cells. PRDX1 has a proliferative effect and is involved in cancer development or progression. Peroxiredoxin-1 is plays a role in redox regulation of the cell. Peroxiredoxin decreases peroxides with reducing equivalents provided through the thioredoxin system but not from glutaredoxin. Peroxiredoxin is involved in eliminating peroxides generated during metabolism. Peroxiredoxin participates in the signaling cascades of growth factors and TNF-alpha by regulating the intracellular concentrations of h(2)o(2).

PPME1 catalyzes the demethylation and inactivation of protein phosphatase (PP2A), a multimeric phosphoserine/ threonine protein phosphatase related to growth inhibition and cell cycle arrest. PPME1 can demethylate PP2A catalytic subunit in vitro and okadaic acid treatment can inhibit this reaction. It is conserved from yeast to human and holds a motif found in lipases having a catalytic triad activated serine as their active site nucleophile.

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.