Pseudomonas aeruginosa B-band lipopolysaccharide genes wbpA and wbpI and their Escherichia coli homologues wecC and wecB are not functionally interchangeable.
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wbpI knockout abolishes B-band LPS.
"Specific knockout mutations in the putative UDP-D-N-acetylglucosamine (UDP-D-GlcNAc) epimerase gene,
wbpI, or the putative UDP-D-N-acetylmannosamine dehydrogenase gene, wbpA, resulted in strains that
no longer produced B-band lipopolysaccharide, confirming the essential roles of these genes in B-band
O antigen synthesis."
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The authors propose that the substrate is di-N-acetylated, explaining why E. coli WecB does not complement.
"These results imply that the P. aeruginosa UDP-D-GlcNAc precursor may be di-N-acetylated prior to
further modification, preventing the E. coli enzymes from recognizing it as a substrate."
Identification and biochemical characterization of two novel UDP-2,3-diacetamido-2,3-dideoxy-alpha-D-glucuronic acid 2-epimerases from respiratory pathogens.
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Purified WbpI 2-epimerizes UDP-GlcNAc3NAcA to UDP-ManNAc3NAcA.
"Data collected from one- and two-dimensional NMR experiments showed that His6-WbpI catalysed the
2-epimerization of UDP-alpha-D-GlcNAc3NAcA, converting it into UDP-alpha-D-ManNAc3NAcA."
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WbpI does not use UDP-GlcNAc, UDP-GlcNAcA or UDP-GlcNAc3NAc.
"Neither enzyme utilized UDP-alpha-D-GlcNAc, UDP-alpha-D-GlcNAcA (UDP-2-acetamido-2,3-dideoxy-alpha-D-glucuronic
acid) or UDP-alpha-D-GlcNAc3NAc (UDP-2,3-diacetamido-2,3-dideoxy-alpha-D-glucose) as substrates."
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniPathway vocabulary mapping
Electronic Gene Ontology annotations created by ARBA machine learning models