@article {1522,
	title = {Indoleamine 2,3-dioxygenase inhibitors from the Northeastern Pacific marine hydroid Garveia annulata},
	journal = {Journal of Natural Products},
	volume = {69},
	number = {10},
	year = {2006},
	note = {ISI Document Delivery No.: 098ZQTimes Cited: 17Cited Reference Count: 20Pereira, Alban Vottero, Eduardo Roberge, Michel Mauk, A. Grant Andersen, Raymond J.},
	month = {Oct},
	pages = {1496-1499},
	type = {Article},
	abstract = {Crude extracts of the marine hydroid Garveia annulata show potent inhibition of indoleamine 2,3-dioxygenase (IDO). Fractionation of the extract led to the identification of the new polyketides annulin C (1), 2-hydroxygarveatin E (4), garveatin E (5), and garvin C (9). Annulins A (2), B (3), and C (1) were found to be submicromolar inhibitors of IDO.},
	keywords = {CANCER, chemotherapy, ENZYME, HUMAN LENS, MECHANISM, METABOLITES, NUCLEAR CATARACT, REJECTION, TOLERANCE, TRYPTOPHAN DEGRADATION},
	isbn = {0163-3864},
	url = {<Go to ISI>://000241562700025},
	author = {Pereira, A. and Vottero, E. and Roberge, M. and Mauk, A. G. and Andersen, R. J.}
}
@article {859,
	title = {Active site residues and mechanism of UDP-glucose dehydrogenase},
	journal = {European Journal of Biochemistry},
	volume = {271},
	number = {1},
	year = {2004},
	note = {ISI Document Delivery No.: 756CXTimes Cited: 16Cited Reference Count: 33},
	month = {Jan},
	pages = {14-22},
	type = {Article},
	abstract = {UDP-glucose dehydrogenase catalyzes the NAD(+)-dependent twofold oxidation of UDP-glucose to give UDP-glucuronic acid. A sequestered aldehyde intermediate is produced in the first oxidation step and a covalently bound thioester is produced in the second oxidation step. This work demonstrates that the Streptococcus pyogenes enzyme incorporates a single solvent-derived oxygen atom during catalysis and probably does not generate an imine intermediate. The reaction of UDP-[6",6"-di-H-2]-D-glucose is not accompanied by a primary kinetic isotope effect, indicating that hydride transfer is not rate determining in this reaction. Studies with a mutant of the key active site nucleophile, Cys260Ala, show that it is capable of both reducing the aldehyde intermediate, and oxidizing the hydrated form of the aldehyde intermediate but is incapable of oxidizing UDP-glucose to UDP-glucuronic acid. In the latter case, a ternary Cys260Ala/aldehyde intermediate/NADH complex is presumably formed, but it does not proceed to product as both release and hydration of the bound aldehyde occur slowly. A washout experiment demonstrates that the NADH in this ternary complex is not exchangeable with external NADH, indicating that dissociation only occurs after the addition of a nucleophile to the aldehyde carbonyl. Studies on Thr118Ala show that the value of k(cat) is reduced 160-fold by this mutation, and that the reaction of UDP-D-[6",6"-di-H-2]-glucose is now accompanied by a primary kinetic isotope effect. This indicates that the barriers for the hydride transfer steps have been selectively increased and supports a mechanism in which an ordered water molecule (H-bonded to Thr118) serves as the catalytic base in these steps.},
	keywords = {ACID, ALDEHYDE DEHYDROGENASE, CONSERVED CYSTEINE RESIDUES, DEHYDROGENASE, ENZYME, GDP-MANNOSE DEHYDROGENASE, GROUP-A STREPTOCOCCI, HISTIDINOL, MOLECULAR CHARACTERIZATION, PSEUDOMONAS-AERUGINOSA, URIDINE DIPHOSPHOGLUCOSE DEHYDROGENASE},
	isbn = {0014-2956},
	url = {<Go to ISI>://000187449200002},
	author = {Ge, X. and Penney, L. C. and van de Rijn, I. and Tanner, M. E.}
}
@article {950,
	title = {Identification and mechanism of a bacterial hydrolyzing UDP-N-acetylglucosamine 2-epimerase},
	journal = {Biochemistry},
	volume = {43},
	number = {44},
	year = {2004},
	note = {ISI Document Delivery No.: 868UVTimes Cited: 13Cited Reference Count: 38},
	month = {Nov},
	pages = {14290-14298},
	type = {Article},
	abstract = {This paper reports the first identification of a fully functional hydrolyzing UDP-N-acetylglucosamine 2-epimerase from a bacterial source. The epimerase (known as SiaA or NeuC from Neisseria meningitidis MC58 group B is shown to catalyze the conversion of UDP-GlcNAc into ManNAc and UDP in the first step of sialic acid (N-acetylneuraminic acid) biosynthesis. The mechanism is proposed to involve an anti elimination of UDP to form 2-acetamidoglucal as an intermediate, followed by the syn addition of water. The observation that the alpha-anomer of ManNAc is the true product and that solvent deuterium is incorporated at C-2 is consistent with this mechanism. The use of the O-18-labeled substrate confirms that the overall hydrolysis reaction proceeds via cleavage of the C-O bond. Furthermore, the putative intermediate 2-acetamidoglucal is shown to serve as a catalytically competent substrate and is enzymatically hydrated to give ManNAc exclusively. Isotope effect studies show that cleavage of the C-H bond is not rate limiting during catalysis. Mutagenesis studies show that three active site carboxylate residues are crucial for catalysis. In two of the mutants that were studied (E122Q and D131N), 2-acetamidoglucal was released from the active site during catalysis, providing direct evidence that the enzyme is capable of catalyzing the anti elimination of UDP from UDP-GlcNAc.},
	keywords = {2-EPIMERASE/N-ACETYLMANNOSAMINE, biosynthesis, CELL-INTERACTIONS, ENZYME, ESCHERICHIA-COLI K1, KINASE, POLYSIALIC ACID, PURIFICATION, RAT-LIVER, SIALIC-ACID, STEREOCHEMISTRY},
	isbn = {0006-2960},
	url = {<Go to ISI>://000224939400045},
	author = {Murkin, A. S. and Chou, W. K. and Wakarchuk, W. W. and Tanner, M. E.}
}
@article {1015,
	title = {Triggering DNAzymes with light: A photoactive C8 thioether-linked adenosine},
	journal = {Journal of the American Chemical Society},
	volume = {126},
	number = {40},
	year = {2004},
	note = {ISI Document Delivery No.: 860QITimes Cited: 31Cited Reference Count: 36},
	month = {Oct},
	pages = {12720-12721},
	type = {Article},
	keywords = {BIOLOGICAL-ACTIVITY, DEOXYRIBOZYME, DNA, ENZYME, MESSENGER-RNA, NUCLEOSIDE, PROTEINS, PURINES},
	isbn = {0002-7863},
	url = {<Go to ISI>://000224357700005},
	author = {Ting, R. and Lermer, L. and Perrin,David M.}
}
@article {454,
	title = {Dehydroalanine-based inhibition of a peptide epimerase from spider venom},
	journal = {Journal of Organic Chemistry},
	volume = {67},
	number = {24},
	year = {2002},
	note = {ISI Document Delivery No.: 620AATimes Cited: 17Cited Reference Count: 42},
	month = {Nov},
	pages = {8389-8394},
	type = {Article},
	abstract = {Ribosomally produced peptides that contain D-amino acids have been isolated from a number of vertebrate and invertebrate sources. In each case, the D-amino acids are introduced by a posttranslational modification of a parent peptide containing only amino acids of the L-configuration. The only known enzyme to catalyze such a reaction is the peptide epimerase (also known as peptide isomerase) from the venom of the funnel web spider, Agelenopsis aperta. This enzyme interconverts two 48-amino-acid-long peptide toxins that differ only by the stereochemistry at a single serine residue. In this paper we report the synthesis and testing of two pentapeptide analogues that contain modified amino acids at the site normally occupied by the substrate serine residue. When the L-chloroalanine-containing peptide 3 was incubated with the epimerase it was converted into the dehydroalanine-containing peptide 4 via an elimination of HCl. The dehydroalanine peptide 4 was independently synthesized and found to act as a potent inhibitor of the epimerase (IC50 = 0.5 muM). These results support a direct deprotonation/reprotonation mechanism in which a carbanionic intermediate is formed. The observed inhibition by 4 can be attributed to the sp(2)-hybridization of the a-carbon in the dehydroalanine unit that mimics the planar geometry of the anionic intermediate.},
	keywords = {ACID, ACTIVE-SITE, ENZYME, GLUTAMATE RACEMASE, GRAMICIDIN-S SYNTHETASE, INFLUENZAE DIAMINOPIMELATE EPIMERASE, INITIATION MODULE PHEATE, MECHANISM, PROLINE RACEMASE, RESIDUES},
	isbn = {0022-3263},
	url = {<Go to ISI>://000179509400011},
	author = {Murkin, A. S. and Tanner, M. E.}
}
@article {5138,
	title = {The structure of L-ribulose-5-phosphate 4-epimerase: An aldolase-like platform for epimerization},
	journal = {Biochemistry},
	volume = {40},
	number = {49},
	year = {2001},
	note = {ISI Document Delivery No.: 500CJTimes Cited: 18Cited Reference Count: 45},
	month = {Dec},
	pages = {14763-14771},
	type = {Article},
	abstract = {The structure of L-ribulose-5 -phosphate 4-epimerase from E. coli has been solved to 2.4 Angstrom resolution using X-ray diffraction data. The structure is homo-tetrameric and displays C-4 symmetry. Each subunit has a single domain comprised of a central beta -sheet flanked on either side by layers of alpha -helices. The active site is identified by the position of the catalytic zinc residue and is located at the interface between two adjacent subunits. A remarkable feature of the structure is that it shows a very close resemblance to that of L-fuculose-1-phosphate aldolase. This is consistent with the notion that both enzymes belong to a superfamily of epimerases/aldolases that catalyze carbon-carbon bond cleavage reactions via a metal-stabilized enolate intermediate. Detailed inspection of the epimerase structure, however, indicates that despite the close overall structural similarity to class II aldolases, the enzyme has evolved distinct active site features that promote its particular chemistry.},
	keywords = {CHEMISTRY, CLASS-II, CLEAVAGE, ENZYME, ESCHERICHIA-COLI, EVOLUTION, GALACTOSE, L-FUCULOSE-1-PHOSPHATE ALDOLASE, MECHANISM, SEQUENCE, SUPERFAMILIES},
	isbn = {0006-2960},
	url = {<Go to ISI>://000172608100005},
	author = {Luo, Y. and Samuel, J. and Mosimann, S. C. and Lee, J. E. and Tanner, M. E. and Strynadka, N. C. J.}
}
@article {4750,
	title = {The structure of UDP-N-acetylglucosamine 2-epimerase reveals homology to phosphoglycosyl transferases},
	journal = {Biochemistry},
	volume = {39},
	number = {49},
	year = {2000},
	note = {ISI Document Delivery No.: 383GTTimes Cited: 58Cited Reference Count: 48},
	month = {Dec},
	pages = {14993-15001},
	type = {Article},
	abstract = {Bacterial UDP-N-acetylglucosamine 2-epimerase catalyzes the reversible epimerization at C-2 of UDP-N-acetylglucosamine (UDP-GlcNAc) and thereby provides bacteria with UDP-N-acetylmannosamine (UDP-ManNAc), the activated donor of ManNAc residues. ManNAc is critical for several processes in bacteria, including formation of the antiphagocytic capsular polysaccharide of pathogens such as Streptococcus pneumoniae types 19F and 19A. We have determined the X-ray structure (2.5 Angstrom) of UDP-GlcNAc 2-epimerase with bound UDP and identified a previously unsuspected structural homology with the enzymes glycogen phosphorylase and T4 phage beta -glucosyltransferase. The relationship to these phosphoglycosyl transferases is very intriguing in terms of possible similarities in the catalytic mechanisms. Specifically, this observation is consistent with the proposal that the UDP-GlcNAc 2-epimerase-catalyzed elimination and re-addition of UDP to the glycal intermediate may proceed through a transition state with significant oxocarbenium ion-like character. The homodimeric epimerase is composed of two similar alpha/beta/alpha sandwich domains with the active site-located in the deep cleft at the domain interface. Comparison of the multiple copies in the asymmetric unit has revealed that the epimerase can undergo a 10 degrees interdomain rotation that is implicated in the regulatory mechanism. A structure-based sequence alignment has identified several basic residues in the active site that may be involved in the proton transfer at C-2 or stabilization of the proposed oxocarbenium ion-like transition state. This insight into the structure of the bacterial epimerase is applicable to the homologous N-terminal domain of the bifunctional mammalian UDP-GlcNAc "hydrolyzing" 2-epimerase/ManNAc kinase that catalyzes the rate-determining step in the sialic acid biosynthetic pathway.},
	keywords = {2-EPIMERASE/N-ACETYLMANNOSAMINE KINASE, ACETYLNEURAMINIC ACID BIOSYNTHESIS, BETA-GLUCOSYLTRANSFERASE, BIFUNCTIONAL ENZYME CATALYZES, CELL-SURFACE SIALYLATION, DNA MODIFYING, enterobacterial common antigen, ENZYME, FIRST 2 STEPS, GLYCOGEN-PHOSPHORYLASE, RAT-LIVER},
	isbn = {0006-2960},
	url = {<Go to ISI>://000165875300001},
	author = {Campbell, R. E. and Mosimann, S. C. and Tanner, M. E. and Strynadka, N. C. J.}
}
@article {4553,
	title = {The inactivation of histidine ammonia-lyase by L-cysteine and oxygen: Modification of the electrophilic center},
	journal = {Journal of the American Chemical Society},
	volume = {121},
	number = {46},
	year = {1999},
	note = {ISI Document Delivery No.: 261NBTimes Cited: 10Cited Reference Count: 23},
	month = {Nov},
	pages = {10840-10841},
	type = {Article},
	keywords = {ACTIVE-SITE, DEHYDROALANINE, ENZYME, PRECURSOR, PSEUDOMONAS-PUTIDA, SERINE-143},
	isbn = {0002-7863},
	url = {<Go to ISI>://000084014300026},
	author = {Galpin, J. D. and Ellis, B. E. and Tanner, M. E.}
}
@article {4197,
	title = {Mechanisms of cellulases and xylanases},
	journal = {Biochemical Society Transactions},
	volume = {26},
	number = {2},
	year = {1998},
	note = {ISI Document Delivery No.: ZT170Times Cited: 22Cited Reference Count: 24664th Meeting of the Biochemical-SocietyDEC 15-17, 1997READING, ENGLANDBiochem Soc},
	month = {May},
	pages = {156-160},
	type = {Proceedings Paper},
	keywords = {ACID-SEQUENCE SIMILARITIES, ACTIVE-SITE, BACILLUS-CIRCULANS XYLANASE, CLASSIFICATION, ENZYME, FAMILIES, GLUCOSIDASE, glycosidase, GLYCOSYL HYDROLASES, HYDROLYSIS, nucleophile},
	isbn = {0300-5127},
	url = {<Go to ISI>://000074056400019},
	author = {Birsan, C. and Johnson, P. and Joshi, M. and MacLeod, A. and McIntosh, L. and Monem, V. and Nitz, M. and Rose, D. R. and Tull, D. and Wakarchuck, W. W. and Wang, Q. and Warren, R. A. J. and White, A. and Withers, S. G.}
}
@article {2871,
	title = {SYNTHESES OF 2-DEOXY-2-FLUORO MONOSACCHARIDE AND OLIGOSACCHARIDE GLYCOSIDES FROM GLYCALS AND EVALUATION AS GLYCOSIDASE INHIBITORS},
	journal = {Carbohydrate Research},
	volume = {249},
	number = {1},
	year = {1993},
	note = {ISI Document Delivery No.: MD387Times Cited: 41Cited Reference Count: 34},
	month = {Oct},
	pages = {77-90},
	type = {Article},
	abstract = {Several fluorinated oligosaccharides, including 2-deoxy-2-fluoro derivatives of cellobiose, maltose, and maltotriose were synthesized by the action of fluorine or acetyl hypofluorite on the corresponding glycal peracetates. Temperature effects on the stereoselectivities of these reactions were examined. Addition of acetyl hypofluorite to several 2-substituted glycals in the gluco or galacto series gave 2,2-disubstituted arabino- or lyxo-hexose derivatives; 3,4,6-tri-O-acetyl-2-fluoro-D-glucal or the analogous galactal yielded 2-deoxy-2,2-difluoro arabino- or lyxo-hexose peracetates, whereas 2-acetoxy-3,4,6-tri-O-acetyl-D-glucal or the analogous galactal gave 2(R)-2-acetoxy-2-fluoro-arabino- or lyxo-hexose peracetates, respectively. 2-Acetamido-3,4,6-tri-O-acetyl-D-glucal gave 2(R)-2-acetamido-2-acetoxy-3,4,6-tri-O-acetyl-alpha-D-arabino-hexopyrano syl fluoride. 2,4-Dinitrophenyl 2-deoxy-2-fluoro-beta-cellobioside was an inactivator of the exoglucanase from Cellulomonas fimi while 2-deoxy-2-fluoro-alpha-maltosyl and alpha-maltotriosyl fluorides were slow substrates of human pancreatic alpha-amylase and rabbit muscle glycogen debranching enzyme, respectively.},
	keywords = {ACETYL HYPOFLUORITE, beta-glucosidase, CATALYTIC FLEXIBILITY, DERIVATIVES, ENZYME, GLYCOSYLASES, hydration, INTERMEDIATE, MECHANISM},
	isbn = {0008-6215},
	url = {<Go to ISI>://A1993MD38700007},
	author = {McCarter, J. D. and Adam,Michael J. and Braun, C. and Namchuk, M. and Tull, D. and Withers, S. G.}
}
@article {7321,
	title = {BINDING-ENERGY AND CATALYSIS - FLUORINATED AND DEOXYGENATED GLYCOSIDES AS MECHANISTIC PROBES OF ESCHERICHIA-COLI (LACZ) BETA-GALACTOSIDASE},
	journal = {Biochemical Journal},
	volume = {286},
	year = {1992},
	note = {ISI Document Delivery No.: JN815Times Cited: 86Cited Reference Count: 40Part 3},
	month = {Sep},
	pages = {721-727},
	type = {Article},
	abstract = {Kinetic parameters for the hydrolysis of a series of deoxy and deoxyfluoro analogues of 2{\textquoteright},4{\textquoteright}-dinitrophenyl beta-D-galactopyranoside by Escherichia coli (lacZ) beta-galactosidase have been determined and rates found to be two to nine orders of magnitude lower than that for the parent compound. These large rate reductions result primarily from the loss of transition-state binding interactions due to the replacement of sugar hydroxy groups, and such interactions are estimated to contribute at least 16.7 kJ (4 kcal).mol-1 to binding at the 3, 4 and 6 positions and more than 33.5 kJ (8 kcal).mol-1 at the 2 position. The existence of a linear free-energy relationship between log(k(cat.)/K(m)) for these compounds and the logarithm of the first-order rate constant for their spontaneous hydrolysis demonstrates that electronic effects are also important and provides direct evidence for oxocarbonium ion character in the enzymic transition state. A covalent intermediate which turns over only extremely slowly (t1/2 = 45 h) accumulates during hydrolysis of the 2-deoxyfluorogalactoside, and kinetic parameters for its formation have been determined. This intermediate is nonetheless catalytically competent, since it re-activates much more rapidly in the presence of the transglycosylation acceptors methanol or glucose, thereby providing support for the notion of a covalent intermediate during hydrolysis of the parent substrates.},
	keywords = {ALPHA-D-GLUCOPYRANOSYL, D-GLUCOPYRANOSYL PHOSPHATES, ENZYME, GLYCOGEN-PHOSPHORYLASE, HYDROLYSIS, inhibitors, OLIGOSACCHARIDE, SITE, SPECIFICITY, SUBSTRATE},
	isbn = {0264-6021},
	url = {<Go to ISI>://A1992JN81500010},
	author = {McCarter, J. D. and Adam,Michael J. and Withers, S. G.}
}
@article {6996,
	title = {VERATRYL ALCOHOL AS A MEDIATOR IN LIGNIN MODEL-COMPOUND BIODEGRADATION},
	journal = {Holzforschung},
	volume = {45},
	number = {1},
	year = {1991},
	note = {ISI Document Delivery No.: FC210Times Cited: 7Cited Reference Count: 22},
	month = {Feb},
	pages = {31-35},
	type = {Article},
	abstract = {Veratryl alcohol and 1,4-dimethoxybenzene were found to be ineffective mediators for the oxidation of anisyl alcohol by the lignin peroxidase model, iron meso-tetra(2,6-dichloro-3-sulfonatophenyl)porphyrin chloride (TDCSPPFeCl). However, veratryl alcohol can mediate the electrochemical oxidation of the polymeric dye Poly B-411. The TDCSPPFeCl catalyzed reactions of lignin model compounds were found to be dependent on pH and the solvent being used. The importance of the mediating role of veratryl alcohol in lignin degradation is discussed.},
	keywords = {APPROACH, BASIDIOMYCETE PHANEROCHAETE-CHRYSOSPORIUM, BIOMIMETIC, BURDS, C BOND-CLEAVAGE, DEGRADATION, ENZYME, IRON PORPHYRINS, LIGNIN, MECHANISM, MEDIATOR, OXIDATION, PEROXIDASE, PORPHYRIN, SYSTEM, VERATRYL ALCOHOL},
	isbn = {0018-3830},
	url = {<Go to ISI>://A1991FC21000006},
	author = {Cui, F. T. and Dolphin, D.}
}
