The enzyme Endoglycosidase H Endo N acetylglucosaminidase H, EC number 3.2.1.96 is a highly specific endoglycosidase which cleaves asparagine linked mannose rich oligosaccharides , but not highly processed complex oligosaccharides from glycoproteins . It is used for research purposes to deglycosylate glycoproteins. Structure and Activity Endoglycosidase H is isolated from Streptomyces plicatus or Streptomyces griseus . Its molecular weight is 29 000 Daltons. The primary structure is described by Robbins 1984 ref Robbins P. W., R. B. Trimble, D. F. Wirth, C. Hering, F.Maley , G. F. Maley, R. Das, B. W. Gibson, N. Royal and K. Biemann. Primary structure of the Streptomyces enzyme endo beta N acetylglucosaminidase H. J Biol Chem 259 7577 7583 1984 . ref Endoglycosidase H cleaves the bond in the diacetylchitobiose core of the oligosaccharide between two N acetylglucosamine GlcNAc subunits directly proximal to the asparagine residue, generating a truncated sugar molecule with one N acetylglucosamine residue remaining on the asparagine ref http www.acciusa.com pdfs northstar 100467 1.pdf Endoglycosidase H, North Star ref . It deglycosylates mannose glycoproteins, but the extent and rate of the deglycosylation depends to a high degree on the nature of the glycoproteins. The deglycosylation rate can be increased by denaturation of the glycoproteins e.g., by carboxymethylation, sulfitolysis or by heating in the presence of sodium dodecyl sulfate . Over 0.02 SDS may inactivate the enzyme. The addition of 0.1 M 2 mercaptoethanol highly increases enzyme activity against glycoproteins containing inter or intra molecular disulfide bridges, unlike detergents like Triton X 100, n Octylglucoside, or zwitterionic detergents ref Trimble, R. B. & Maley, F. 1984 Anal. Biochem. 141, 515 522 ref . Biochemical Applications Endoglycosidase H Endo H is commonly used by cell biologists to monitor posttranslational modification in the Golgi apparatus . Most proteins destined for the cell sur ... more details
N acetylgalactosaminidase http www.expasy.org cgi bin nicezyme.pl?3.2.1.49 EC 3.2.1.49 is a glycoside hydrolase from bacteria and animals. The human gene that codes for this enzyme is NAGA gene NAGA . Mutations in this gene and the deficiency in alpha N acetylgalactosaminidase activity have been identified as the cause of Schindler disease . ref name pmid2243144 cite journal author Wang AM, Schindler D, Desnick R title Schindler disease the molecular lesion in the alpha N acetylgalactosaminidase gene that causes an infantile neuroaxonal dystrophy journal J. Clin. Invest. volume 86 issue 5 pages 1752 6 year 1990 month November pmid 2243144 doi 10.1172 JCI114901 issn pmc 296929 ref A N acetylgalactosaminidase or Nagalase http enzyme.expasy.org EC 3.2.1.49 EC 3.2.1.49 is a glycoside hydrolase from bacteria and animals and promotes immune suppression by inactivating Macrophages . Alpha N acetyl galactosaminidase alpha NaGalase has been reported to accumulate in serum of cancer patients and be responsible for deglycosylation of Gc protein, which is a precursor of Gc MAF mediated macrophage activation cascade, finally leading to immunosuppression in advanced cancer patients. Alpha NaGalase The biochemical characterization of alpha NaGalase from several human tumor cell lines were studied. We also examined its effect on the potency of GcMAF to activate mouse peritoneal macrophage to produce superoxide in GcMAF mediated macrophage activation cascade. The specific activity of alpha NaGalases from human colon tumor cell line HCT116, human hepatoma cell line HepG2, and normal human liver cells Chang liver cell line were evaluated using two types of substrates GalNAc alpha PNP exo type substrate and Gal beta GalNAc alpha PNP endo type substrate . Tumor derived alpha NaGalase having higher activity than normal alpha NaGalase, had higher substrate specificity to the exo type substrate than to the endo type substrate, and still maintained its activity at pH 7. GcMAF enhance supe ... more details
Gc MAF or Gc protein derived macrophage activating factor is a partially deglycosylated Vitamin D binding protein VDBP also known as Gc protein. The a functional change in the Gc protein Vitamin D binding protein caused by serial deglycosylation. is known as GcMAF. Gc MAF is extremely potent and will at very low concentrations activate, regulate and expand macrophage s which are the central processing unit of the immune system and capable of modulating and controlling both the innate and cognate immune systems . ref Paul Cheney MD, PhD September 2011 http www.bgli.nl index.php?option com content&view article&id 116 compassionate use of ghp gcmaf in cfs me&catid 6 research&Itemid 2 Compassionate use of GHP GcMAF in CFS M.E. ref A Macrophage Activating Factor MAF is a lymphokine that primes macrophage s to become Cytotoxicity cytotoxic to tumor s. It also controls the expression of Ia antigen s on the macrophage cell surface. ref name pmid12554797 cite journal author Mosser DM title The many faces of macrophage activation journal J. Leukoc. Biol. volume 73 issue 2 pages 209 12 year 2003 month February pmid 12554797 doi 10.1189 jlb.0602325 url issn ref History In 1999 Nobuto Yamamoto published his first report mentioning the use of Gc MAF on Tumor Bearing Mice. ref Yoshihiko Koga , Venkateswara R. Naraparaju & Nobuto Yamamoto 1999 http onlinelibrary.wiley.com doi 10.1046 j.1525 1373.1999.d01 3.x abstract Wiley online Library DOI 10.1046 j.1525 1373.1999.d01 3.x ref The first report of the application of Gc MAF in research on humans dates back to the same year by another research group. Preliminary research projects focused on the function of Gc MAF in cancer and reports were scarce. Since 2010 research has expanded into the application and or the role of Gc MAF or macrophages in HIV, ref Immunotherapy of HIV infected patients with Gc protein derived macrophage activating factor GcMAF http onlinelibrary.wiley.com doi 10.1002 jmv.21376 abstract Immunotherapy of HIV infec ... more details
TOCright Deoxyribozymes or DNA enzymes or catalytic DNA , or DNAzymes are deoxyribonucleic acid DNA molecules with catalyst catalytic action. In contrast to the RNA ribozyme that has many catalytic capabilities, DNA is only associated with gene DNA replication replication and nothing else. The reasons are that DNA lacks specific functional group s and that DNA prefers the double coil conformation in which potential catalytic sites are shielded. In comparison to protein s built up from 20 different monomer s both RNA and DNA have a much more restricted set of monomers 4 to choose from which limits the construction of interesting catalytic sites. For these reasons DNAzymes exist only in the laboratory. Discovery The first deoxyribozyme was discovered in 1994 ref cite journal journal Chem Biol. year 1994 month December volume 1 issue 4 pages 223 9 title A DNA enzyme that cleaves RNA author Breaker RR, coauthors Joyce GF. pmid 9383394 doi 10.1016 1074 5521 94 90014 0 ref by current Yale Professor Ronald R. Breaker while a postdoctoral fellow in the laboratory of Prof. Gerald Joyce at The Scripps Research Institute in La Jolla, CA. This deoxyribozyme assists in lead ion dependent RNA cleaving operations. Catalytic amplification was found to be 100 fold compared to the uncatalysed reaction. Many other deoxyribozymes have since been developed that catalyse DNA phosphorylation, DNA adenylation , DNA deglycosylation , porphyrin metalation , thymine dimer photoreversion and DNA cleavage. Of particular interest are DNA ligase s. ref cite journal title Deoxyribozymes DNA catalysts for bioorganic chemistry author Scott K. Silverman journal Org. Biomol. Chem. year 2004 volume 2 pages 2701 06 url http www.scs.uiuc.edu scott SilvermanPub30.pdf format PDF doi 10.1039 B411910J pmid 15455136 issue 19 ref These molecules have demonstrated remarkable chemoselectivity in RNA branching reactions. Although each repeating unit in a RNA strand owns a free hydroxyl group, the DNA ligase takes ... more details
and the importance of deglycosylation in their crystallization journal Eur. J. Biochem. volume 262 ... complexes of interleukin 10 stoichiometry and the importance of deglycosylation in their crystallization ... more details
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