Glycosyltransferase

Theb1,3-glycosyltransferase enzymes identi®ed to date share several conserved regions and conserved cysteine res-idues, all being located in the putative catalytic domain. To investigate the importance of these motifs and cysteines for the enzymatic activity, 14 mutants of the murine b1,3-galactosyltransferase-I gene were constructed and expressed in Sf9 insect cells. Seven mutations abolished the galacto-syltransferase activity.

7p research12 29-04-2013 38 3   Download

The plant enzyme arbutin synthase isolated from cell sus-pension cultures ofRauvolfia serpentinaand heterologously expressed inEscherichia coliis a member of the NRD1b family of glycosyltransferases. This enzyme was used to prove, by site-directed mutagenesis, suggested catalytic domains and reaction mechanisms proposed for enzyme-catalyzed glycosylation. Replacement of amino acids far from the NRD domain do not significantly affect arbutin synthase activity.

6p tumor12 20-04-2013 42 3   Download

Cyclodextrin glycosyltransferase (CGTase) uses ana-retain-ingdoubledisplacementmechanismtocatalyze threedistinct transglycosylation reactions. To investigate these reactions as catalyzed by the CGTase fromThermoanaerobacterium thermosulfurigenesthe enzyme was overproduced (8 mgÆL )1 culture) usingBacillus subtilisas a host. Detailed analysis revealed that the three reactions proceed via different kinetic mechanisms.

8p tumor12 20-04-2013 50 4   Download

Saccharomyces cerevisiaeGpi3p is the UDP-GlcNAc-bind-ing andpresumed catalytic subunit of the enzyme that forms GlcNAc-phosphatidylinositol in glycosylphosphatidylinosi-tol biosynthesis. It is anessential proteinwithanEX7 Emotif that is conserved in four families of retaining glycosyl-transferases. All Gpi3ps contain a cysteine residue four residues C-terminal to EX7E. To test their importance for Gpi3p functionin vivo,Glu289 and297 in theEX7 Emotif of S.

8p fptmusic 12-04-2013 31 2   Download

Leukocyte rolling is an important step for the successful recruitment of leu-kocytes into tissue and occurs predominantly in inflamed microvessels and in high endothelial venules of secondary lymphoid organs. Leukocyte roll-ing is mediated by a group of C-type lectins, termed selectins. Three differ-ent selectins have been identified – P-, E- and L-selectin – which recognize and bind to crucial carbohydrate determinants on selectin ligands.

13p inspiron33 25-03-2013 48 4   Download

Cyclodextrin glycosyltransferase catalyzes the formation of a mixture of cyclodextrins from starch by an intramolecular transglycosylation reaction. To manipulate the product specificity of thePaenibacillussp. A11 and Bacillus maceranscyclodextrin glycosyltransferases towards the preferential formation of c-cyclodextrin (CD8), crosslinked imprinted proteins of both cyclodextrin glycosyltransferases were prepared by applying enzyme imprinting and immobilization methodologies.

10p galaxyss3 21-03-2013 43 3   Download

The glycosyltransferase enzymes (Lgts) responsible for the biosynthesis of the lipooligosaccharide-derived oligosaccharide structures from Moraxella catarrhalishave been investigated. This upper respiratory tract pathogen is responsible for a spectrum of illnesses, including otitis media (middle ear infection) in children, and contributes to exacerbations of chronic obstruct-ive pulmonary disease in elderly patients.

14p galaxyss3 19-03-2013 34 4   Download

The dihydrochalcone phlorizin (phloretin 2¢-glucoside) contributes to the flavor, color and health benefits of apple fruit and processed products. A genomics approach was used to identify the geneMdPGT1in apple (Ma-lus x domestica) with homology to the UDP-glycosyltransferase 88 family of uridine diphosphate glycosyltransferases that show specificity towards flavonoid substrates.

11p galaxyss3 07-03-2013 48 3   Download

UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (GalNAc transferases), which initiate mucin-type O-glycan biosynthesis, have broad acceptor substrate specificities, and it is still unclear how they recognize peptides with different sequences.

9p media19 05-03-2013 40 3   Download

Cell wall biosynthesis is a key target for antibacterial drugs. The major constituent of the bacterial wall, peptidoglycan, is a netlike polymer responsible for the size and shape of the cell and for resisting osmotic pres-sure. It consists of glycan chains of repeating disaccharide units cross-linked through short peptide chains.

9p viettel02 19-02-2013 47 3   Download

Nhóm máu di truyền từ cả cha lẫn mẹ. Type nhóm máu ABO được kiểm soát bởi một gene đơn độc có 3 alleles (gen đẳng vị): i, IA, và IB. H1-Các alleles ABO di truyền từ cha mẹ, và kiểu gen (genotype) ABO ở con Gen đơn độc này mã hoá một enzyme glycosyltransferase—là enzyme làm biến đổi lượng carbohydrate của các antigens trong hồng cầu. H2-Cấu trúc hồng cầu thuộc các nhóm máu O, A, B và AB khác nhau Gene này khu trú trên nhánh dài của nhiễm sắc thể thứ 9 (9q34). Allele IA cho ra nhóm...

7p truongthiuyen1 08-06-2011 216 14   Download