PPN Pyrophosphate: A New Reagent for the Preparation of Nucleoside Triphosphates
摘要:
Tris{bis(triphenylphosphoranylidene) ammonium} (PPN) pyrophosphate was accessed via aqueous precipitation and desiccation. The reagent was investigated as a replacement for highly hygroscopic alkylammonium salts in Ludwig-Yoshikawa reactions for the preparation of nucleoside-5 '-triphosphates.
The Shewanella woodyi galactokinase pool phosphorylates glucose at the 6-position
摘要:
Galactokinases are a class of enzymes which belong to the GHMP (galactokinase, homoserine kinase, mevalonate kinase, and phosphomevalonate kinase) superfamily and catalyse the phosphorylation of galactose in the first step of the Leloir pathway. Here we report the discovery of three enzymes from Shewanella woodyi which have been classified as galactokinases based on sequence similarity. However, each of these enzymes show little to no significant activity towards galactose and instead exhibit a strong preference for glucose. Furthermore, in contrast to the usual galactose-1-phosphate product of the galactokinase-catalysed reaction, these enzymes produce glucose-6-phosphate. This radical change in enzyme functionality is postulated to be linked to the mutation of a glycine residue which is conserved in all other sequenced galactokinases. (C) 2017 Elsevier Ltd. All rights reserved.
A chemoenzymatic route to N-acetylglucosamine-1-phosphate analogues: substrate specificity investigations of N-acetylhexosamine 1-kinase
作者:Li Cai、Wanyi Guan、Motomitsu Kitaoka、Jie Shen、Chengfeng Xia、Wenlan Chen、Peng George Wang
DOI:10.1039/b904853g
日期:——
Reports an efficient chemoenzymatic production of an N-acetylhexosamine 1-phophate analogues library by N-acetylhexosamine 1-kinase (NahK) and describes the respective substrate specificity on this enzyme.
The Nonribosomal Peptide Synthetase Enzyme DdaD Tethers <i>N</i><sub>β</sub>-Fumaramoyl-<scp>l</scp>-2,3-diaminopropionate for Fe(II)/α-Ketoglutarate-Dependent Epoxidation by DdaC during Dapdiamide Antibiotic Biosynthesis
作者:Marie A. Hollenhorst、Stefanie B. Bumpus、Megan L. Matthews、J. Martin Bollinger、Neil L. Kelleher、Christopher T. Walsh
DOI:10.1021/ja1072367
日期:2010.11.10
The gene cluster from Pantoea agglomerans responsible for biosynthesis of the dapdiamide antibiotics encodes an adenylation-thiolation didomain protein, DdaD, and an Fe(II)/α-ketoglutarate-dependent dioxygenase homologue, DdaC. Here we show that DdaD, a nonribosomalpeptidesynthetase module, activates and sequesters N(β)-fumaramoyl-l-2,3-diaminopropionate as a covalently tethered thioester for subsequent
A view on phosphate ester photochemistry by time-resolved solid state NMR. Intramolecular redox reaction of caged ATP
作者:Alexey V. Cherepanov、Elena V. Doroshenko、Jörg Matysik、Simon de Vries、Huub J. M. De Groot
DOI:10.1039/b806677a
日期:——
carbocation intermediate is involved in the reaction. The beta-phosphate oxygen atom of ATP is protonated first, indicating its proximity to the reaction center, possibly within hydrogen bonding distance. The residual linewidth kinetics are interpreted in terms of chemical exchangeprocesses, hydrogen bonding of the beta-phosphate oxygen atom and evolution of the hydrolytic equilibrium at the triphosphate
作者:Ry R. Forseth、Saori Amaike、Daniel Schwenk、Katharyn J. Affeldt、Dirk Hoffmeister、Frank C. Schroeder、Nancy P. Keller
DOI:10.1002/anie.201207456
日期:2013.1.28
Biosynthetic crosstalk: Most geneclusters in fungi are orphans with no known associated metabolites. NMR‐based comparative metabolomics was used to identify the products of two highly homologous orphan clusters in Aspergillus flavus. The two clusters encode partially redundant biosynthetic pathways that produce overlapping sets of novel fungal alkaloids, feature NRPS‐like genes with unusual functions,
a group of structurally diverse natural products with distinct activities. Some are synthesized through an inter-molecular esterification step catalysed by nonribosomal peptide synthetase (NRPS). In bacteria, the formation of the intra-molecular ester bond is usually catalysed by a thioesterase domain of NRPS. However, the mechanism by which fungal NRPSs perform this process remains unclear. Herein