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Coproporphyrinogen Oxidase (CPOX) which is localized to the internal membrane space of erythrocytes takes part in the 6th phase of heme biosynthesis. CPOX catalyzes the oxidative decarboxylation of propionic acid side chains of rings A and B of coproporphyrinogen III. Mutations in human CPOX gene forecast the clinical result of the disease, with either hepatic hereditary coproporphyria or hematological manifestations of erythropoietic harderoporphyria.

Lysostaphin, an endopeptidase specific for the cell wall peptidoglycan of staphylococci, is an extremely potent anti-staphylococcal agent. Lysostaphin is used as a research and diagnostic tool. Because it lyses staphylococci efficiently, it is widely used when preparing staphylococcal DNA or other cellular components for genetic and biochemical studies and for the preparation of protoplasts for transformation. Preparation and analysis of bacterial DNA has become a powerful tool used by clinical and other microbiologists in epidemiological studies aimed at tracing sources of infection or bacterial contamination.

Inositol monophosphatase 3 (IMPAD1) belongs to the inositol monophosphatase family. IMPAD1 is restricted to the Golgi apparatus and catalyzes the hydrolysis of phosphoadenosine phosphate (PAP) to adenosine monophosphate (AMP). IMPAD1 gene mutations cause the GRAPP type chondrodysplasia with joint dislocations, and a pseudogene of the IMPAD1 gene is located on the long arm of chromosome 1.

Phosphomevalonate kinase (PMVK) is a cytosolic enzyme. PMVK is expressed highly in the heart, liver, skeletal muscle, kidney and pancreas and slightly lower in the brain, placenta, and lung. PMVK catalyzes the conversion of mevalonate 5-phosphate into mevalonate 5-diphosphate in the fifth reaction of the cholesterol biosynthetic pathway. Induced by sterol, PMVK participates in isopentenyl diphosphate biosynthesis via the mevalonate pathway.

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.

GOT1 is a pyridoxal phosphate-dependent enzyme which exists in cytoplasmic and mitochondrial forms, GOT1 and GOT2, which participate in amino acid metabolism and the urea and tricarboxylic acid cycles. Both enzymes are homodimeric and show close homology.

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.

DsbA appears to be necessary for correct formulation of disulfide bonds in exported proteins in vivo. DsbA is useful as a standard in immunoblotting. This protein catalyses the reduction and exchange of disulfide bonds and the oxidation of free sulfhydryl groups in vitro. It is the strongest oxidant of the thioredoxin superfamily. This thio/disulfide oxidoreductase is required for efficient disulfide bond formation in the periplasm of E. coli.

The AsnRS enzyme is a member of the ligases family, specifically those forming carbon-oxygen bonds in aminoacyl-tRNA and related compounds. An asparagine-tRNA ligase is an enzyme which catalyzes the chemical reaction: ATP + L-asparagine + tRNAAsn AMP + diphosphate + L-asparaginyl-tRNAAsn. The three substrates of the AsnRS enzyme are ATP, L-asparagine, and tRNA(Asn), whereas its three products are AMP, diphosphate, and L-asparaginyl-tRNA(Asn).

NQO1 belongs to the NAD(P)H dehydrogenase (quinone) family and encodes a cytoplasmic 2-electron reductase. NQO1 acts as an imperative part of cellular antioxidant defense by detoxifying quinines therefore preventing the formation of reactive oxygen species. It seems that NQO1 serves as a quinone reductase relating to conjugation reactions of hydroquinons involved in detoxification pathways in addition to biosynthetic processes such as the vitamin K-dependent gamma-carboxylation of glutamate residues in prothrombin synthesis. Altered NQO1 expression is seen in many tumors and also linked to Alzheimer’s disease. NQO1 gene mutations are linked to tardive dyskinesia which is an increased risk of hematotoxicity after exposure to benzene, and susceptibility to various forms of cancer.

Epoxide Hydrolase 1 Microsomal (EPHX1) is a vital biotransformation enzyme which transfers epoxides from the degradation of aromatic compounds to trans-dihydrodiols that can be conjugated and excreted from the body. Epoxide hydrolase plays a role in both activation and detoxification of epoxides. Mutations in EPHX1 trigger preeclampsia, epoxide hydrolase deficiency or increased epoxide hydrolase activity.

Kallikreins are a subgroup of serine proteases having various physiological functions. Many kallikreins are implicated in carcinogenesis and some have potential of becoming novel cancer and other disease biomarkers. Kallikrein-13 (KLK13) is one of the fifteen kallikrein subfamily members located in a cluster on chromosome 19. KLK13 gene expression is regulated by steroid hormones and may be useful as a marker for breast cancer.

Kallikrein-15 (KLK15) is one of the 15 kallikrein subfamily members located in a cluster on chromosome 19. KLK15 contains numerous polyadenylation sites and alternative splicing results in multiple transcript variants encoding different isoforms. KLK15 is over expressed in prostate cancer and therefore uses as a diagnostic or prognostic marker for prostate cancer.

Polymerase III Polypeptide K, known as PORL3K, is a small vital subunit of RNA polymerase III. The carboxy-terminal domain of PORL3K owns a sequence which is very similar to the carboxy-terminal domain of an RNA polymerase II elongation factor. PORL3K takes part in sensing and limiting infection by intracellular bacteria and DNA viruses. PORL3K is also plays a role as nuclear and cytosolic DNA sensor which takes part in the innate immune response.

GDA is a member of the ATZ/TRZ family and is in charge for the hydrolytic deamination of guanine. GDA takes part in microtubule assembly. Multiple transcript variants encoding different isoforms have been found for GDA.

Cyclophilin-D is a member of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and speeds up the protein folding. Cyclophilin-D possess PPIase activity and binds to the immunosuppressant cyclosporin-A. Cyclophilin-D is very well known that its overexpression suppresses the apoptosis in cancer cell. Cyclophilin-D suppresses apoptotic cell death by the use of mitochondrial hexokinase-2 dependent mechanism in cancer cells.

Luciferase is a general term for the class of oxidative enzymes used in bioluminescence and is distinct from a photoprotein. Luciferase catalyzes a bioluminescent reaction which involves the substrate luciferin as well as Mg2+ and ATP, produces green light with a wavelength of 562 nm. Luciferase from firefly is broadly used as a reporter for studying gene regulation and function, and for pharmaceutical screening.

Glutathione S-transferase, also known as GST, is an antioxidant enzyme. It is the primary defense mechanism from reactive oxygen in the cell. The enzyme GST reduces hydroperoxides of lipids via a Se-independent glutathione peroxidase actions. GST detoxifies peroxidation of lipids bi-products, for example 4-hydroxynonenal.

Mitogen-Activated Protein Kinase 6 (MAP2K6) is a part of the dual specificity protein kinase family. MAP2K6 phosphorylates and activates p38 MAP kinase in response to inflammatory cytokines or environmental stress. MAP2K6 is a vital component of the MAP kinase signal transduction pathway. MAP2K6 takes part in various cellular processes such as stress induced cell cycle arrest and apoptosis.

Chitodextrinase is a unique membrane-bound endoenzyme. The chitodextrinase enzyme cleaves soluble oligomers, but not chitin, to the di- and trisaccharides. Chitodextrinase is unable to solubilize chitin, but it can catalyze the hydrolysis of high to low molecular weight soluble chitin oligosaccharides.

T7 RNA polymerase active enzyme synthesizes RNA at an increasing degree of that of E. coli RNA polymerase and it terminates transcription often. T7 RNA polymerase is very selective for initiation at its own promoter sequences and is resistant to antibiotics that inhibit E. coli RNA polymerase. In-vitro transcription of mRNA is achieved via bacteriophage T7 RNA polymerase using its ability to produce full-length RNA transcripts with high reliability, thoughT7 RNAP can manufacture as well immunostimulatory by products for example dsRNA which affect protein expression.

Zinc-alpha-2-glycoprotein (ZAG) is found in body fluids such as serum, sweat, and seminal and breast cyst fluids. It is identical in amino acid sequence to tumor-derived lipid mobilizing factor (LMF), a protein associated with the dramatic loss of adipose body stores in cancer cachexia, and has been shown to stimulate lipolysis by adipocytes in vivo and in vitro. A role for ZAG has been proposed in the regulation of body weight, and age-dependent changes in genetically influenced obesity, and also it regulates melanin production by normal and malignant melanocytes. It has also recently been classified as a novel adipokine in that it is produced by both white and brown fat adipocytes and may act in a local autocrine fashion in the reduction of adiposity in cachexia. Controlling ZAG/LMF's activity could be life-saving in the management of certain cancers and other cachexiainducing conditions, and its possible normal role in body fat store homeostasis is deserving of understanding in its own right. ZAG exhibits a class I major histocompatibility complex (MHC) fold but is a soluble protein rather than being anchored to plasma membranes and does not associate with alpha-2-microglobulin in humans. Like antigen-presenting MHC class I proteins, ZAG has an open apical groove, and X-ray crystallography of human derived ZAG revealed an unidentifiable electron density in a similar position to that occupied by antigenic peptides in classical MHC proteins and glycolipids in isoforms of CD1. This presumptive ligand is not a peptide, and the groove is too small to hold a glycolipid such as is presented by CD1 isoforms. By analogy with all other MHC class I-related proteins that have an open apical groove [some do not ], occupancy by a ligand is probably crucial to ZAG's biological function. Despite all of the structural and biochemical evidence that ZAG binds a ligand, none has so far been found by extraction from protein isolated from biological fluids. This difficulty could be because the ligand is labile, heterogeneous, or readily lost during purification procedures. Knowing more about how ZAG interacts with the compounds it has been found to bind, both natural and artificial, will inform searches for the elusive ligand(s) and its/their role in ZAG's signaling function.