Gene Ontology annotation based on Enzyme Commission mapping
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniPathway vocabulary mapping
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Electronic Gene Ontology annotations created by ARBA machine learning models
Functional characterization of WaaL, a ligase associated with linking O-antigen polysaccharide to the core of Pseudomonas aeruginosa lipopolysaccharide.
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waaL knockout LPS lacks A-band and B-band O antigen and SR-LPS, restored by complementation; the mutant has swimming and twitching defects.
"waaL is required for the attachment of O-antigen repeat units to the core"
WaaL of Pseudomonas aeruginosa utilizes ATP in in vitro ligation of O antigen onto lipid A-core.
Membrane topology mapping of the O-antigen flippase (Wzx), polymerase (Wzy), and ligase (WaaL) from Pseudomonas aeruginosa PAO1 reveals novel domain architectures.
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Reporter fusions and GFP fusions place WaaL in the inner membrane with a large periplasmic loop carrying essential His303.
"Protein orientation in the inner membrane was confirmed via C-terminal fusion to green fluorescent protein."
The WaaL O-antigen lipopolysaccharide ligase has features in common with metal ion-independent inverting glycosyltransferases.
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WaaL ligation needs no ATP or Mg2+, and E. coli and P. aeruginosa WaaL do not hydrolyse ATP; WaaL resembles metal-independent inverting GTs.
"E. coli and Pseudomonas aeruginosa WaaL proteins cannot catalyze ATP hydrolysis in vitro"
Escherichia coli and Pseudomonas aeruginosa lipopolysaccharide O-antigen ligases share similar membrane topology and biochemical properties.
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PEG-Mal labeling gives a common topology for E. coli and P. aeruginosa WaaL; P. aeruginosa WaaL shares the functional properties of E. coli WaaL.
"we also demonstrate that P. aeruginosa WaaL shares similar functional properties with E. coli WaaL"
The effect of loss of O-antigen ligase on phagocytic susceptibility of motile and non-motile Pseudomonas aeruginosa.
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waaL deletion in PA14 and PAK removes O antigen but does not abolish swimming or biofilm formation.
"ΔwaaL mutation in P. aeruginosa did not abrogate swimming motility nor ability of the bacteria to form biofilms"