Glycosylation is the enzymatic process that attaches glycans to glycoprotein protein s, glycolipid lipid ... biopolymers found in cells along with DNA , RNA , and proteins . Glycosylation is a form of co translational ... reticulum ER undergo glycosylation. It is an enzyme directed site specific process, as opposed to the non enzymatic chemical reaction of glycation . Glycosylation is also present in the cytoplasm ... serine C linked glycans, a rare form of glycosylation where a sugar is added to a carbon on a tryptophan ... on some secreted glycoproteins. Experiments have shown that glycosylation in this case is not a strict requirement for proper folding, but the unglycosylated protein degrades quickly. Glycosylation .... Mechanisms There are various mechanisms for glycosylation, although most share several common features ref name varki Glycosylation, unlike glycation , is an enzymatic process The donor molecule is often an activated nucleotide sugar The process is site specific. Types of Glycosylation N linked glycosylation main N linked glycosylation N linked glycosylation is important for the folding of some eukaryotic proteins. The N linked glycosylation process occurs in eukaryotes and widely in archaea , but very rarely in bacteria . O linked glycosylation main O linked glycosylation O linked glycosylation is a form of glycosylation occurring in the Golgi apparatus . ref name Flynne2008 cite book author ... 45 ref Phospho Serine Glycosylation Xylose , fucose , mannose , and GlcNAc phospho serine glycans ... of the most commonly modified proteins, however this form of glycosylation appears elsewhere as well ... atom like a nitrogen or oxygen . GPI Anchors Glypiation A special form of glycosylation is the GPI anchor . This form of glycosylation functions to attach a protein to a hydrophobic lipid anchor, via ... Chemical glycosylation Fucosylation References Reflist External links http www.ncbi.nlm.nih.gov books bv.fcgi?rid glyco Online textbook of glycobiology with chapters about glycosylation http www.dkfz ... more details
A chemical glycosylation reaction involves the coupling of a sugar to a glycosyl acceptor forming a glycoside . ref Cite book publisher Blackwell Publishing isbn 978 1850759133 last Boons first Geert Jan coauthors Karl J. Hale title Organic synthesis with carbohydrates date 2000 ref ref Crich, D. Lim, L. Org. React. 2004 , 64 , 115. doi http dx.doi.org 10.1002 0471264180.or064.02 10.1002 0471264180.or064.02 ref ref Bufali, S. Seeberger, P. Org. React. 2006 , 68 , 303. doi http dx.doi.org 10.1002 0471264180.or064.02 10.1002 0471264180.or064.02 ref If the acceptor is another sugar, the product is an oligosaccharide . The reaction involves coupling a glycosyl donor to a glycosyl acceptor via activation utilizing a suitable activator. The reactions often result in a mixture of products due to the creation of a new stereogenic centre at the anomer anomeric position of the glycosyl donor . The formation of a glycosidic linkage allows for the synthesis of complex polysaccharides which may play important roles in biological processes and pathogenesis and therefore having synthetic analogs of these molecules ... The glycosylation reaction involves the coupling of a glycosyl donor and a glycosyl acceptor via initiation ... to glucose . To better understand this, the mechanism of a glycosylation reaction must be considered ... outcome of a glycosylation reaction may in certain cases be affected by the type of protecting ... and yield of the glycosylation reaction. Typically, electron withdrawing group s such as acetyl ... were first introduced for use in glycosylation reactions in 1901 by Koenigs Knorr reaction Koenigs ... thumb 600px Thioglycosides used in glycosylation reactions as donours can be activated under a wide ... anomeric hydroxyl group. File TCAPrep.gif centre thumb 600px Typical activating groups for glycosylation ... Notable synthetic products Below are a few examples of some notable targets obtained via a series of glycosylation ... 7388. ref See also Glycosylation Glycosyl transferase Glycorandomization Glycation Carbohydrate ... more details
O linked glycosylation is a form of glycosylation occurring in the Golgi apparatus . ref name Flynne2008 cite book author William G. Flynne title Biotechnology and Bioengineering url http books.google.com books?id WEBBP5IYqJQC&pg PA45 accessdate 13 November 2010 year 2008 publisher Nova Publishers isbn 9781604560671 pages 45 ref O N acetylgalactosamine O GalNAc O linked glycosylation occurs at a later stage during protein processing, probably in the Golgi apparatus . This is the addition of N acetyl galactosamine to serine or threonine residues by the enzyme UDP N acetyl D galactosamine polypeptide N acetylgalactosaminyltransferase EC number 2.4.1.41 , followed by other carbohydrates such as galactose and sialic acid . This process is important for certain types of proteins such as proteoglycan s, which involves the addition of glycosaminoglycan chains to an initially unglycosylated proteoglycan core protein. These additions are usually serine O linked glycoproteins, which seem to have one of two main functions. One function involves secretion to form components of the extracellular matrix , adhering one cell to another by interactions between the large sugar complexes of proteoglycans ... of this form of glycosylation, which clearly appears to act in concert with phosphorylation ... to both prokaryotes and eukaryotes. Collagen Glycosylation Many lysine s in collagen are hydroxylated ... . This glycosylation is required for the proper functioning of collagen. Glycosylation of hydroxlysine occurs in the ER. Hydroxyproline Glycosylation Proline is also hydroxylated in collagen, however, no glycosylation occurs here as the hydroxyprolines are necessary for hydrogen bonding in the collagen ... on hydroxyproline, but this would appear to be an extremely rare form of glycosylation. Otherwise ... being reported in the literature. Glycosylation of Glycogenin Liver and muscle glycogenin carries a glucose .... Glycosylation of Ceramide Either a galactose or a glucose can be added to a hydroxyl on the lipid ... more details
as a glycosylation sequon . After attachment, once the protein is correctly folded, the three glucose ... may take place. However, glycosylation itself does not seem to be as necessary for correct transport targeting of the protein, as one might think. Studies involving drugs that block certain steps in glycosylation, or mutant cells deficient in a glycosylation enzyme, still produce otherwise structurally ... is the only reported example of N linked glycosylation on an amino acid other than asparagine ... more details
Infobox Disease Name Congenital disorders of glycosylation Image Caption DiseasesDB 2012 DiseasesDB mult ... MedlinePlus eMedicineSubj eMedicineTopic MeshID A congenital disorder of glycosylation previously ... in which glycosylation of a variety of Tissue biology tissue protein s and or lipid s is deficient or defective. Congenital disorder s of glycosylation are sometimes known as CDG syndrome s. They often ... for the synthesis of the lipid linked oligosaccharide precursor of N linked glycosylation. In 1998 .... ref Haeuptle, M.A., and Hennet, T. Congenital disorders of glycosylation an update on defects ..., L., and Mundlos, S. Impaired glycosylation and cutis laxa caused by mutations in the vesicular H ATPase subunit ATP6V0A2. 2008 Nat. Genet. 40, 32 4. ref were found to be causing the glycosylation defect in some CDG patients. Also, defects disturbing other glycosylation pathways than the N linked one ... GCS1 2p13 p12 Congenital disorder of glycosylation type IIc 2C OMIM2 266265 SLC35C1 11p11.2 2D OMIM2 ... disorder of glycosylation type 1a journal Ophthalmic Genet. volume 24 issue 2 pages 81 8 year 2003 ... Sun L, Eklund EA, Chung WK, Wang C, Cohen J, Freeze HH title Congenital disorder of glycosylation ... Glycosylation and known defects A biologically very important group of carbohydrates is the asparagine ... life. A vast amount of carbohydrate binding molecules lectins depend on correct glycosylation for appropriate ... in the genes involved in N linked glycosylation constitute the molecular background to most ... polyprenol to dolichol and is mutated in a congenital glycosylation disorder. 2010 Cell ... of Glycosylation Type Ij. 2003 Hum. Mut., 22, 144 50. ref Loss of the first mannosyltransferase ... in the N glycosylation pathway causes congenital disorder of glycosylation type Ik. 2004 Hum. Mol. Genet ..., L., and K rner, C. A new type of congenital disorders of glycosylation CDG Ii provides new insights ... analysis of a defect in the human ALG9 gene definition of congenital disorder of glycosylation ... more details
Infobox disease Name Congenital disorder of glycosylation type IIc Image Alt Caption DiseasesDB ICD10 ICD9 ICDO OMIM 266265 MedlinePlus eMedicineSubj eMedicineTopic MeshID GeneReviewsID GeneReviewsName Congenital disorder of glycosylation type IIc or Leukocyte adhesion deficiency 2 LAD 2 is a type of leukocyte adhesion deficiency attributable to the absence of neutrophil sialyl LewisX , a ligand of P and E selectin on vascular endothelium . ref Etzioni A, Harlan JM. Cell adhesion and leukocyte adhesion defects. In Ochs HD, Smith CIE, Puck JM, eds. Primary immunodeficiency diseases a molecular and genetic approach. Oxford Oxford University Press, 2007 550 564. ref It is associated with SLC35C1 . ref name pmid18541720 cite journal author Yakubenia S, Frommhold D, Sch lch D, et al. title Leukocyte trafficking in a mouse model for leukocyte adhesion deficiency II congenital disorder of glycosylation IIc journal Blood volume 112 issue 4 pages 1472 81 year 2008 month August pmid 18541720 doi 10.1182 blood 2008 01 132035 url http www.bloodjournal.org cgi pmidlookup?view long&pmid 18541720 ref This disorder was discovered in two unrelated Israeli boys 3 and 5 years of age, each the offspring of consanguineous parents. Both had severe mental retardation , short stature, a distinctive facial appearance, and the Bombay hh blood phenotype, and both were secretor and Lewis negative. They both had had recurrent severe bacterial infections similar to those seen in patients with leukocyte adhesion deficiency 1 LAD 1 , including pneumonia, peridontitis, otitis media, and localized cellulitis. Similar to that in patients with LAD 1, their infections were accompanied by pronounced leukocytosis 30,000 to 150,000 mm sup 3 sup but an absence of pus formation at sites of recurrent cellulitis . In vitro ... CDG IIc, a new type of congenital disorders of glycosylation, as a GDP fucose transporter deficiency. Nat Genet. 2001 28 1 73 76. ref See also Congenital disorder of glycosylation References ... more details
Unreferenced stub auto yes date December 2009 Orphan date February 2009 Covalent modulation is the alteration of a protein s shape and function by covalent bonding of chemical groups to it. Types Phosphorylation Glycosylation DEFAULTSORT Covalent Modulation Category Proteins Protein stub ... more details
A consensus site is a term in molecular biology that refers to a site on a protein that is often modified in a particular way. Modifications may be N or O linked glycosylation , phosphorylation ref http www.nature.com nrm journal v2 n10 glossary nrm1001 760a glossary.html ref , tyrosin sulfation or other. References Reflist Categories Category Molecular biology ... more details
Orphan date January 2011 The Helferich method may refer to Glycosylation of an alcohol using a glycosyl acetate as glycosyl donor and a Lewis acid e.g. a metal halide as promoter ref B. Helferich, E. Schmitz Hillebrecht, Ber. 66, 378 1933 ref Glycosylation of an alcohol using a glycosyl halide as a glycosyl donor and a mercury element mercury salt as promoter cf the Koenigs Knorr reaction , which uses silver salts as promoters . ref B. Helferich, J. Zirner, Chem. Ber. 95, 2604 1962 ref References reflist Category Organic reactions chemistry stub ... more details
of oligosaccharide. 6 Release its substrates. Congenital disorder s of glycosylation CDG types CDG syndrome s are genetic disorder s of the glycosylation pathway. They are labelled Type I if the defective ... of OST in the N linked glyocsylation pathway or involves Glycosylation O linked glycosylation O linked glycosylation . ref marquardt03 References How to add a footnote NOTE Footnotes in this article ... duvet02 3 a Glycosylation of the hepatitis C virus envelope protein E1 occurs posttranslationally ... glycosylation the clash of the titans , B. Imperiali, Accounts of Chemical Research 30, 452 459, 1997. Note marquardt03 Congenital disorders of glycosylation review of their molecular bases, clinical ... more details
precursor dolichol PP Man 7 GlcNAc 2 required for protein glycosylation. Mutations in this gene have been associated with congenital disorder of glycosylation type Ig CDG Ig characterized by abnormal N glycosylation. ref name entrez cite web title Entrez Gene ALG12 asparagine linked glycosylation ... of glycosylation CDG update and new developments. journal J. Inherit. Metab. Dis. volume 27 issue ... J, Carchon H title Congenital disorders of glycosylation a booming chapter of pediatrics. journal ... P Man Man7GlcNAc2 PP dolichyl mannosyltransferase causes congenital disorder of glycosylation type ... defect in congenital disorder of glycosylation type lg. journal Hum. Mol. Genet. volume ... Zdebska E, Bader Meunier B, Schischmanoff PO, et al. title Abnormal glycosylation of red cell membrane band 3 in the congenital disorder of glycosylation Ig. journal Pediatr. Res. volume 54 issue ... more details
protein Name glycosylation dependent cell adhesion molecule 1 caption image width HGNCid 18023 Symbol GLYCAM1 AltSymbols EntrezGene 644076 OMIM RefSeq XM 927461 UniProt Q8IVK1 PDB ECnumber Chromosome 12 Arm q Band 13.2 LocusSupplementaryData Glycosylation dependent cell adhesion molecule 1 GLYCAM1 is a proteoglycan ligand expressed on cells of the high endothelial venule s in lymph nodes. It is able to bind to the receptor L selectin during inflammation, acting as a homing beacon for leukocyte s expressing the receptor to enter the site of inflammation. ref name robspath cite book title Robbins Pathologic Basis of Disease last Cotran coauthors Kumar, Collins publisher W.B Saunders Company location Philadelphia id 0 7216 7335 X ref External links MeshName GlyCAM 1 References reflist biochem stub ... more details
Unreferenced date November 2008 Ovotransferrin is a glycoprotein of egg white albumen. Transferrin s are iron binding proteins and acute phase reactant s of animal serum. The sequence of ovotransferrin is similar to that observed for serum transferrin in many species. However, structurally this protein differs from its serum counterpart because of its glycosylation pattern. See also Egg allergy biochem stub Category Proteins ... more details
Unreferenced date April 2009 A glycosyl donor is a carbohydrate mono or oligosaccharide which will react with a suitable glycosyl acceptor to form a new glycosidic bond . By convention, the donor is the member of this pair which contains the resulting anomer ic carbon of the new glycosidic bond. Background Empty section date July 2010 Examples Empty section date July 2010 See also Chemical glycosylation Glycosyl halide Armed and disarmed saccharides Carbohydrate chemistry References reflist Category Carbohydrate chemistry Category Organic reactions ... more details
Fucosylation The process of adding fucose sugar units to a molecule. It is a type of Glycosylation . It is important clinically ref http www.ncbi.nlm.nih.gov pubmed 16973733 ref ref http jb.oxfordjournals.org cgi content abstract 143 6 725 ref , especially in cancer ref http www.springerlink.com content u653792327435h24 ref ref http www.jbc.org cgi content abstract 281 40 29797 ref . It is performed by fucosyltransferase enzymes. References reflist Category Carbohydrate chemistry biochem stub ca Glicosilaci ... more details
Collectin of 46 kDa CL 46 is a collectin protein. It has two cysteine residues on the N terminal segment, a hydrophilic loop near the carbohydrate recognition domain s binding site, and a N glycosylation site in the collagen region. It is expressed in bovine liver and thymus glands and binds to pathogens, prompting elimination by macrophages. ref http www.jimmunol.org cgi content full 169 10 5726 ref References reflist immunology stub Category Proteins Category Collectins ... more details
PBB geneid 440138 Asparagine linked glycosylation protein 11 homolog is an enzyme that in humans is encoded by the ALG11 gene . ref name entrez cite web title Entrez Gene asparagine linked glycosylation 11 url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 440138 accessdate ref See also Congenital disorder of glycosylation References reflist Further reading refbegin 2 cite journal author Rohozinski J, Lamb DJ, Bishop CE title UTP14c is a recently acquired retrogene associated with spermatogenesis and fertility in man. journal Biol. Reprod. volume 74 issue 4 pages 644 51 year 2006 pmid 16354793 doi 10.1095 biolreprod.105.046698 cite journal author Rind N, Schmeiser V, Thiel C, et al. title A severe human metabolic disease caused by deficiency of the endoplasmatic mannosyltransferase hALG11 leads to congenital disorder of glycosylation Ip. journal Hum. Mol. Genet. volume 19 issue 8 pages 1413 24 year 2010 pmid 20080937 doi 10.1093 hmg ddq016 cite journal author Ewing RM, Chu P, Elisma F, et al. title Large scale mapping of human protein protein interactions by mass spectrometry. journal Mol. Syst. Biol. volume 3 issue pages 89 year 2007 pmid 17353931 doi 10.1038 msb4100134 pmc 1847948 refend genetics stub ... more details
PBB geneid 199857 UDP N acetylglucosamine transferase subunit ALG14 homolog is a protein that in humans is encoded by the ALG14 gene . ref name entrez cite web title Entrez Gene asparagine linked glycosylation 14 homolog S. cerevisiae url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 199857 accessdate ref ref name pmid15615718 cite journal author Chantret I, Dancourt J, Barbat A, Moore SE title Two proteins homologous to the N and C terminal domains of the bacterial glycosyltransferase Murg are required for the second step of dolichyl linked oligosaccharide synthesis in Saccharomyces cerevisiae journal J. Biol. Chem. volume 280 issue 10 pages 9236 42 year 2005 month March pmid 15615718 doi 10.1074 jbc.M413941200 url issn ref Asparagine N glycosylation is an essential modification that regulates protein folding and stability. ALG13 and ALG14 this protein constitute the UDP GlcNAc transferase, which catalyzes a key step in endoplasmic reticulum N linked glycosylation. ref name pmid17686769 cite journal author Averbeck N, Keppler Ross S, Dean N title Membrane topology of the Alg14 endoplasmic reticulum UDP GlcNAc transferase subunit journal J. Biol. Chem. volume 282 issue 40 pages 29081 8 year 2007 month October pmid 17686769 doi 10.1074 jbc.M704410200 url issn ref See also Congenital disorder of glycosylation References reflist Further reading refbegin 2 cite journal author Strausberg RL, Feingold EA, Grouse LH, et al. title Generation and initial analysis of more than 15,000 full length human and mouse cDNA sequences. journal Proc. Natl. Acad. Sci. U.S.A. volume 99 issue 26 pages 16899 903 year 2002 pmid 12477932 doi 10.1073 pnas.242603899 pmc 139241 cite journal author Gao XD, Tachikawa H, Sato T, et al. title Alg14 recruits Alg13 to the cytoplasmic face of the endoplasmic reticulum to form a novel bipartite UDP N acetylglucosamine transferase required for the second step of N linked glycosylation. journal J. Biol. Chem. volume 280 i ... more details
disorder of glycosylation type Id CDG Id . journal Hum. Mutat. volume 23 issue 5 pages 477 86 ... al. title Congenital disorder of glycosylation type Id clinical phenotype, molecular analysis, prenatal diagnosis, and glycosylation of fetal proteins. journal Pediatr. Res. volume 58 issue 2 pages 248 ... more details
Orphan date February 2009 Expert subject Molecular and Cellular Biology date February 2009 Unreferenced date February 2009 An antigenic determinant is the molecular aspect or moiety of a molecule that lets an antibody complement it and thus by definition, makes the molecule an antigen classified further, an immunogen within an organism . A Protein can underlie further modification within a biochemical pathway such as glycosylation, phosphorylation or proteolysis. This, by altering the structure of the protein, can produce new epitope s which are called neoantigenic determinants as they give rise to new lat. neo antigenic determinants and require separate, specific antibodies for recognition. References reflist Category Immune system molecular cell biology stub ... more details
A glycosyl acceptor is any suitable nucleophile containing molecule that will react with a glycosyl donor to form a new glycosidic bond . By convention, the acceptor is the member of this pair which did not contain the resulting anomer ic carbon of the new glycosidic bond. Since the nucleophilic atom of the acceptor is typically an oxygen atom, this can be remembered using the mnemonic of the acceptor is the alcohol. A glycosyl acceptor can be a mono or oligosaccharide that contains an available nucleophile, such as an unprotected hydroxyl. Background Empty section date July 2010 Examples Empty section date July 2010 See also Chemical glycosylation Glycosyl halide Armed and disarmed saccharides Carbohydrate chemistry References reflist Category Carbohydrate chemistry Category Organic reactions ... more details
Multiple issues orphan October 2010 context December 2010 unreferenced October 2010 Caspr is a contactin associated protein . Caspr is part of the neurexin family of protiens. It lies in the paranodal section of the myelin sheath , between the Nodes of Ranvier containing Na channels, and K channels in the juxtaparanodal region. Its role is for myelin sheath attachment along with contactin laterally in a cis complex. In staining, it shows up as green with immunohistochemical steps, and along with VNa red shows a red green contrast to stain for defects in myelin sheath, and size of Nodes of Ranvier. In Western Blotting it has a predicted Molecular Weight around 156 kDa but due to a number of potential glycosylation sites, is 180kDa. Category Human proteins ... more details
Entrez Gene ALG6 asparagine linked glycosylation 6 homolog S. cerevisiae, alpha 1,3 glucosyltransferase ... residue to the growing lipid linked oligosaccharide precursor of N linked glycosylation. Mutations in this gene are associated with congenital disorders of glycosylation type Ic. ref name entrez cite web title Entrez Gene ALG6 asparagine linked glycosylation 6 homolog S. cerevisiae, alpha 1,3 glucosyltransferase .... title Multi allelic origin of congenital disorder of glycosylation CDG Ic. journal Hum. Genet. volume ... gene in a patient with congenital disorder of glycosylation Ic. journal Mol. Genet. Metab. volume 70 ... losing enteropathy in a congenital disorder of glycosylation. journal Am. J. Pathol. volume ... N, Barrot S, et al. title A broad spectrum of clinical presentations in congenital disorders of glycosylation ... for molecular diagnosis of congenital disorders of glycosylation CDG . journal Eur. J. Hum. Genet ..., Freeze HH title Identification of a frequent variant in ALG6, the cause of Congenital Disorder of Glycosylation ... disorder of glycosylation Ic due to a de novo deletion and an hALG 6 mutation. journal Biochem. Biophys ... more details
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