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Glycosyltransferases: structures, functions, and mechanisms.
The expected two-step double-displacement mechanism is rendered less likely by the lack of conserved architecture in the region where a catalytic nucleophile would be expected, and a mechanism involving a short-lived oxocarbenium ion intermediate now seems the most likely, with the leaving phosphate serving as the base. Expand
Mechanisms of enzymatic glycoside hydrolysis.
The determination of a large number of three-dimensional structures of glycosidases, both free and in complex with ligands, has provided valuable new insights into glycosidase catalysis, especiallyExpand
Crystal structure of the retaining galactosyltransferase LgtC from Neisseria meningitidis in complex with donor and acceptor sugar analogs
The 2 Å crystal structures of the complex of LgtC with manganese and UDP 2-deoxy-2-fluoro-galactose in the presence and absence of the acceptor sugar analog 4′-deoxylactose give valuable insights into the unique catalytic mechanism and, as the first structure of a glycosyltransferase in complex with both the donor and acceptor sugars, provide a starting point for inhibitor design. Expand
Structural analysis of the sialyltransferase CstII from Campylobacter jejuni in complex with a substrate analog
The first structure of a sialyltransferase is reported, CstII from Campylobacter jejuni, a highly prevalent foodborne pathogen, and structural, mutagenesis and kinetic data provide support for a novel mode of substrate binding and glycosyl transfer mechanism, including essential roles of a histidine and two tyrosine residues. Expand
Mechanistic and Structural Analysis of a Family 31 α-Glycosidase and Its Glycosyl-enzyme Intermediate*
We have determined the first structure of a family 31 α-glycosidase, that of YicI from Escherichia coli, both free and trapped as a 5-fluoroxylopyranosyl-enzyme intermediate via reaction withExpand
Catalysis by hen egg-white lysozyme proceeds via a covalent intermediate
A general catalytic mechanism for all retaining β-glycosidases that includes substrate distortion, formation of a covalent intermediate, and the electrophilic migration of C1 along the reaction coordinate is formulated. Expand
Mutagenesis of glycosidases.
Surprisingly little progress has been made on altering specificities through mutagenesis, although recent results suggest that gene shuffling coupled with effective screens will provide the most effective approach. Expand
The Donor Subsite of Trehalose-6-phosphate Synthase
Both complexes unveil the donor subsite interactions, confirming a strong similarity to glycogen phosphorylases, and reveal substantial conformational differences to the previously reported complex with UDP and glucose 6-phosphate. Expand
The structure of human pancreatic α‐amylase at 1.8 Å resolution and comparisons with related enzymes
It is notable that the N‐terminal glutamine residue of human pancreatic α‐amylase undergoes a posttranslational modification to form a stable pyrrolidone derivative that may provide protection against other digestive enzymes. Expand
The Structure of Clostridium perfringens NanI Sialidase and Its Catalytic Intermediates*
The crystal structures suggested that NanI is able to hydrate 2-deoxy-2,3-dehydro-N-acetylneuraminic acid to N-acetelneuramic acid, and this was confirmed by NMR, and a mechanism for this activity is suggested. Expand