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The OmpA protein is one of the main outer-membrane proteins of a large array of Gram-negative bacteria such as A.salmonicida, Shigella dysenteriae and E.coli.OmpA’s major physiological functions include maintenance of the structural integrity and morphology of the cells and porin activity, as well as a role in conjugation and bacteriophage binding.Achromogenic atypical Aeromonas salmonicida is the causative agent of goldfish ulcer disease.Virulence of this bacterium is associated with the production of a paracrystalline outer membrane A-layer protein.The species specific structural gene for the monomeric form of A-protein was cloned into a pET-3d plasmid in order to express and produce a recombinant form of the protein in E.coli BL21(DE3). The induced protein was isolated from inclusion bodies by a simple solubilization-renaturation procedure and purified by ion exchange chromatography on Q-Sepharose to over 95% pure monomeric protein.Recombinant A-protein was compared by biochemical, immunological and molecular methods with the A-protein isolated from atypical A.salmonicida bacterial cells by the glycine and the membrane extraction methods.

Ubiquitin-conjugating enzyme E2S (UBE2S) belongs to the ubiquitin-conjugating enzyme family. UBE2S is able to form a thiol ester linkage with ubiquitin in a ubiquitin activating enzyme-dependent manner, a typical property of ubiquitin carrier proteins. UBE2S catalyzes the covalent attachment of ubiquitin to other proteins. UBE2S acts as a crucial factor of the anaphase promoting complex/cyclosome (APC/C), which is a cell cycle-regulated ubiquitin ligase that controls progression through mitosis. UBE2S acts by purposely elongating 'Lys-11'-linked polyubiquitin chains initiated by the E2 enzyme UBE2C/UBCH10 on APC/C substrates, augmenting the degradation of APC/C substrates by the proteasome and promoting mitotic exit. UBE2S also acts by elongating ubiquitin chains initiated by the E2 enzyme UBE2D1/UBCH5 in vitro; it is nevertheless uncertain whether UBE2D1/UBCH5 acts as an E2 enzyme for the APC/C in vivo. UBE2S is also involved in ubiquitination and consequent degradation of VHL, resulting in an accumulation of HIF1A.

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

Gankyrin (proteasome 26S subunit) is a multicatalytic proteinase oncoprotein commonly overexpressed in most hepatocellular carcinomas. Proteasomes are found throughout eukaryotic cells at a high concentrations and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. Gankyrin interacts with S6 ATPase of the 19S regulatory particle of the 26S proteasome. Gankyrin is involved in theregulation of the phosphorylation of the retinoblastoma protein by CDK4, and to enhance the ubiquitinylation of p53 by MDM2. Gankyrin consists of 7 ankyrin repeats and is structurally similar to I kappa Bs. Gankyrin acts as a regulatory subunit of the 26s proteasome which is involved in the atp-dependent degradation of ubiquitinated proteins. Gankyrin is involved in progression of esophageal squamous cell carcinoma. gankyrin plays an oncogenic role especially in early stages of human epatocarcinogenesis. Gankyrin binds to NF-kappaB and suppresses its activity at the transcription level by modulating acetylation through SIRT1. Structural comparison between Gankyrin & p16(INK4A) identified numerous residues of gankyrin that are potentially important for CDK4 binding.

Short/branched chain specific acyl-CoA dehydrogenase (ACADSB) belongs to the acyl-CoA dehydrogenase family of enzymes which catalyze the dehydrogenation of acyl-CoA derivatives in the metabolism of fatty acids or branch chained amino acids. ACADSB catalyzes the degradation of L-isoleucine while having the highest affinity for (s)-2-methylbutyryl-CoA, isobutyryl-CoA and 2-methylhexanoyl-CoA as substrates. ACADSB may use valproyl-CoA as substrate. ACADSB gene defects cause the short/branched-chain acyl-CoA dehydrogenase deficiency (SBCADD), which is an autosomal recessive disorder characterized by an increase of 2-methylbutyrylglycine and 2-methylbutyrylcarnitine in blood and urine.

UGDH is part of the UDP-glucose/GDP-mannose dehydrogenase family and is a widely expressed enzyme localized in the liver. UGDH transfers UDP-glucose to UDP-glucuronate and thus takes part in the biosynthesis of glycosaminoglycans such as hyaluronan, chondroitin sulfate, and heparan sulfate. These glycosylated products are ordinary molecules of the extracellular matrix and participate in signal transduction, cell migration, and cancer growth and metastasis.

The Defensin family are highly similar in their protein sequence and are microbicidal & cytotoxic peptides made by neutrophils. Beta Defensin-1 is an antimicrobial peptide having the resistance of epithelial surfaces to microbial colonization. Beta Defensin-1 has close proximity to Defensin Alpha-1 and has been implicated in the pathogenesis of cystic fibrosis.
Skin of patients having atopic dermatitis patients and mycosis fungoides (non-lesional and lesional) show lower human Beta Defensin-1 mRNA expression and higher human Beta Defensin-2 and human Beta Defensin-3 mRNA expression.
Beta Defensin is highly expressed by epithelial cells.
Beta-defensin 1 may play a role in the pathogenesis of severe sepsis.

GAPDH is a catalytic enzyme normally known to play a role in glycolysis. GAPDH exists as a tetramer composed of 36-kDa subunits and has a range of intracellular functions. GAPDH catalyzes the reversible reduction of 1,3-bisphosphoglycerate to glyceraldehyde 3-phosphophate in the presence of NADPH. Besides functioning as a glycolytic enzyme in cytoplasm, GAPDH has function in intracellular processes such as membrane fusion, microtubule bundling, phosphotransferase activity, nuclear RNA export, DNA replication and DNA repair. GAPDH catalyzes a vital energy-yielding step in carbohydrate metabolism, the reversible oxidative phosphorylation of glyceraldehyde-3-phosphate in the presence of inorganic phosphate and nicotinamide adenine dinucleotide (NAD). The enzyme exists as a tetramer of identical chains.

MMP-3 enzyme is also known as Stromelysin-1or as Transin-1 which hydrolyzes natural collagen at physiological pH and temperature. It dissolves the intervertebral nucleus pulposus and annulus fibrosus of Herniated Lumbar Intervertebral Disk . MMP-3 hydrolyzes components of the extracellular matrix like proteoglycan, laminin, fibronectin, gelatin and collagen types III, IV and IX. It also activates pro-MMP-9 and pro-MMP-8 and superactivates plasmin activated MMP-1. MMP-3 is secreted as a latent proenzyme and is activated by a variety of proteinases, e.g. plasmin, trypsin, chymotrypsin, cathepsin G or human neutrophil elastase. MMP-3 was found to be capable of activating the precursor of IL1-beta.

Peroxiredoxin 6 (PRDX6) belongs to the thiol-specific antioxidant protein family. PRDX6 is a bifunctional enzyme with 2 distinct active sites. PRDX6 is involved in redox regulation of the cell and can reduce Hydrogen peroxide and short chain organic, fatty acid, and phospholipid hydroperoxides. PRDX6 may have a role in the regulation of phospholipid turnover as well as in protection against oxidative injury. Furthermore, PRDX6 eases the oxidative stress and TGF-beta-induced abnormalities of human trabecular meshwork cells. In addition, PRDX6 is necessary for blood vessel integrity in injured skin.
At acidic pH, PRDX6 binds to reduced phospholipids, however at cytosolic pH PRDX6 binds only to phospholipids that are oxidized which is compatible with the role for PRDX6 in the repair of peroxidized cell membranes. Hydrogen peroxide-mediated hyperoxidation of PRDX6 induces cell cycle arrest at the G2/M transition via up-regulation of iPLA2 activity. Overexpression of PRDX6 is linked to oligodendroglioma.

Cathepsin D is synthesized as a 54kDa precursor, which is proteolytically processed to an intermediate 48kDa single chain, which matures into more stable 34kDa and 14kDa two chain form. It is an estrogen-regulated lysosomal protease that has been suggested to facilitate cancer cell migration and invasion by digesting the basement membrane, extracellular matrix, and xonnective tissue. Because of its mitogenic and proteolytic activities, it has been implicated as a prognostic marker in many tumor types. Cathepsin D is expressed in epithelial cells as well as in macrophages.

Elastase-2 (ELANE) is a serine protease that belongs to the chymotrypsin family. ELANE breaks down elastin, an elastic fiber together with collagen and controls the mechanical properties of connective tissue. The neutrophil form breaks down the Outer membrane protein A (OmpA) of E. coli and other Gram-negative bacteria. ELANEis inhibited by the acute-phase protein alpha 1-antitrypsin (A1AT), which binds almost irreversibly to the active site of elastase and trypsin.A1AT is usually secreted by the liver cells into the serum. A1AD leads to uninhibited destruction of elastic fiber by elastase.

E2 17-beta-dehydrogenase 1 (HSD17B1) is a member of the short-chain dehydrogenases/reductases (SDR) family. The HSD17B1 protein advances the reduction of estrogens and androgens. In addition, the HSD17B1 has a 20-alpha-HSD activity. HSD17B1 preferentially uses NADH.

ASS1 is involved in the urea cycle, which is a sequence of chemical reactions that is localized in liver cells. The urea cycle processes excess nitrogen that is generated as the body uses proteins. The surplus nitrogen is used to create a molecule called urea, which is excreted from the body in urine.

Suppressor of Cytokine Signaling 3, also known as SOCS3 belongs to the SOCS family; in addition SOCS3 is a member of the STAT-induced STAT inhibitor (SSI). The SSI family members are cytokine-inducible negative regulators of cytokine signaling. The expression of SOCS3 is induced by different cytokines, including IL6 and IL10. SOCS3 can bind to JAK2 kinase, and inhibit the activity of JAK2 kinase. Studies of the mouse counterpart of SOCS3 have shown the roles of SOCS3 in the negative regulation of fetal liver hematopoiesis, and placental development.

Pin 1 is a peptidyl-prolyl cis/trans isomerase (PPIase) which interacts with NIMA and essential for cell cycle regulation Pin1 is nuclear PPIase containing a WW protein interaction domain, and is structurally and functionally related to Ess1/Ptf1, an essential protein in budding yeast. PPIase activity is necessary for Ess1/Pin1 function in yeast. Pin1 is thus an essential PPIase that regulates mitosis presumably by interacting with NIMA and attenuating its mitosis-promoting activity. Substrates of Pin1 include the mitotic regulators (Cdc25 phosphatase and NIMA, PLK I, Wee, and Myt1 kinases), several transcription factors like b-Catenin, c-Jun, and the tumor suppressor protein p53, and some specific proteins like the RNA Pol II, the cytoskeleton protein tau, and the G1/S protein Cyclin D1.

Glutamate Decarboxylase 1 (GAD1) is one of several forms of glutamic acid decarboxylase. GAD1 is responsible for catalyzing the production of gamma-aminobutyric acid from L-glutamic acid. A pathogenic role for the GAD1 enzyme has been identified in the human pancreas since it has been detected as an autoantigen and an autoreactive T cell target type II diabetes. The GAD1 protein may also have a role in the stiff man syndrome. GAD1 enzyme deficiency leads to pyridoxine dependency with seizures. GAD1 also catalyzes the production of GABA.

AHCY is an enzyme that catalyzes the reversible hydrolysis of S-adenosylhomocysteine (AdoHcy) to adenosine (Ado) and L-homocysteine (Hcy). AHCY controls the intracellular S-adenosylhomocysteine (SAH) concentration that is crucial for transmethylation reactions. AHCY deficiency causes hypermethioninemia.

Aldolase C Fructose-Bisphosphate (ALDOC) belongs to the class I fructose-bisphosphate aldolase family. ALDOC is a glycolytic enzyme which catalyzes the reversible aldol cleavage of fructose-1,6-biphosphate and fructose 1-phosphate to dihydroxyacetone phosphate and either glyceraldehyde-3-phosphate or glyceraldehydes respectively. ALDOC is expressed exclusively in the hippocampus and Purkinje cells of the brain.

DUSP10 is a member of the protein-tyrosine phosphatase family. DUSPs inactivate their target kinases by dephosphorylating both the phosphoserine/threonine and phosphotyrosine residuesb and negatively regulate members of the MAPK superfamily which is linked with cellular proliferation and differentiation. DUSP10 interacts with MAPK14 and MAPK8. DUSP10 blocks in mammalian cells the enzymatic activation of MAP kinases with the selectivity p38 approximately JNK/SAPK >> ERK.

Phosphoribosylaminoimidazole Carboxylase (PAICS) is an enzyme involved in nucleotide biosynthesis and particularly in purine biosynthesis. PAICS is a bifunctional enzyme containing phosphoribosylaminoimidazole carboxylase activity at its N-terminal region and phosphoribosylaminoimidazole succinocarboxamide synthetase at its C-terminal region. PAICS catalyzes the conversion of 5'-phosphoribosyl-5-aminoimidazole(AIR) into 5'-phosphoribosyl-4-carboxy-5-aminoimidazole (CAIR) as described in the reaction. PAICS catalyzes steps six and seven of purine biosynthesis.

6PGD is the second dehydrogenase in the pentose phosphate shunt. Pentose is neccesary for nucleic acid biosynthesis. The pentose phosphate cycle is a major source of NADPH 6PGD deficiency is usually asymptomatic, and the inheritance of this disorder is autosomal dominant. PGD deficiency raises the erythrocyte pyruvate kinase levels of activity and decreases glutathione synthetase, resulting in hemolysis.

Caspase 2 Apoptosis-Related Cysteine Peptidase (CASP2) is a part of the cysteine-aspartic acid protease (caspase) family. CASP2 takes part in the activation cascade of caspases responsible for apoptosis execution. CASP2 is also responsible for inactivating proteins essential for cell survival. The proteolytic cleavage of CASP2 is induced by a variety of apoptotic stimuli.