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Identification and Characterization of Bacterial Cutinase*
The cutinase from Thermobifida fusca was induced by cutin and purified to homogeneity by following p-nitrophenyl butyrate hydrolyzing activity, the first report of cut inase encoding genes from bacterial sources.
KpsF Is the Arabinose-5-phosphate Isomerase Required for 3-Deoxy-d-manno-octulosonic Acid Biosynthesis and for Both Lipooligosaccharide Assembly and Capsular Polysaccharide Expression in Neisseria
The function ofkpsF of Neisseria meningitidis and the homologues of kpsF in encapsulated K1 and K5Escherichia coli is identified and defined and KpsF was shown to be the arabinose-5-phosphate isomerase, an enzyme not previously identified in prokaryotes, that mediates the interconversion of ribulose 5-ph phosphate and arabinoses 5- phosphate.
Modification of Lipopolysaccharide with Colanic Acid (M-antigen) Repeats in Escherichia coli*
It is shown that a highly mucoid strain of E. coli K-12 ligates CA repeats to a significant proportion of lipopolysaccharide (LPS) core acceptor molecules, forming the novel LPS glycoform, which has implications for potential underlying mechanisms coordinating the synthesis of various surface polysaccharides.
Detoxifying Escherichia coli for endotoxin-free production of recombinant proteins
The preparation and characterization of endotoxin-free E. coli strains are described, the direct production of recombinant proteins with negligible endotoxin contamination is demonstrated, and Lipid IVA does not trigger an endotoxic response in humans typical of bacterial LPS chemotypes.
New Insights into the Evolutionary Links Relating to the 3-Deoxy-D-arabino-heptulosonate 7-Phosphate Synthase Subfamilies*
Results suggest that “feedback regulation” may indeed be the evolutionary link between the two classes/subfamilies and it is likely that DAHPSs evolved from a primitive unregulated member of the AroAIβ subfamily.
Structure and Mechanism of 3-Deoxy-d-manno-octulosonate 8-Phosphate Synthase*
In the active site of DAH7P synthase the two substrates PEP and erythrose 4-phosphate appear to bind in a configuration similar to that proposed for PEPand A5P in theactive site of KDO8P synth enzyme, suggesting that KDO 8P synthases evolved from a common ancestor and that they adopt the same catalytic strategy.
Redefining the requisite lipopolysaccharide structure in Escherichia coli.
These results challenge the established E. coli Kdo2-lipid A dogma, indicating that the previously observed and well-documented dependence of cell viability on the synthesis of Kdo stems from a lethal pleiotropy precipitated after the depletion of the carbohydrate, rather than an inherent need for the Kdo molecule itself as an indispensable structural component of the OM LPS layer.
Substrate and Metal Complexes of 3-Deoxy-d-manno-octulosonate-8-phosphate Synthase from Aquifex aeolicus at 1.9-Å Resolution
The crystal structure of the A. aeolicus enzyme is reported, which was determined by molecular replacement using E. coli KDO8PS as a model and which appears to alternate catalysis between the active sites located on one face of the tetramer and those located on the other face.
Structural and mechanistic analysis of the membrane-embedded glycosyltransferase WaaA required for lipopolysaccharide synthesis
WaaA is a key enzyme in the biosynthesis of LPS, a critical component of the outer envelope of Gram-negative bacteria. Embedded in the cytoplasmic face of the inner membrane, WaaA catalyzes the