Gene Ontology annotation through association of InterPro records with GO terms
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Prediction of lipoprotein signal peptides in Gram-negative bacteria.
An ABC transport system that maintains lipid asymmetry in the gram-negative outer membrane.
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Defines the Mla pathway (including MlaA/VacJ) as preventing phospholipid accumulation in the outer leaflet of the OM.
"We have identified an ABC transport system in Escherichia coli with predicted import function that serves to prevent PL accumulation in the outer leaflet of the OM."
Osmoporin OmpC forms a complex with MlaA to maintain outer membrane lipid asymmetry in Escherichia coli.
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MlaA interacts specifically with OmpC and OmpF, and the porin interaction suffices to target unlipidated MlaA to the OM.
"This interaction is sufficient to localize MlaA lacking its lipid anchor to the OM."
Architectures of Lipid Transport Systems for the Bacterial Outer Membrane.
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Purified MlaA forms a stable complex with OmpF that binds MlaC; model in which MlaA-OmpC/F extracts lipids and hands them to MlaC.
"Binding of MlaC to the lipid-bound MlaA-OmpC/OmpF complex results in lipid transfer to the hydrophobic pocket of MlaC, where it is protected from solvent."
Structural basis for maintenance of bacterial outer membrane lipid asymmetry.
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Crystal structures and MD show MlaA is a monomeric alpha-helical OM protein in the inner leaflet with a central amphipathic pore that selectively accepts outer-leaflet phospholipids.
"MlaA represents a lipid transport protein that selectively removes outer leaflet phospholipids to help maintain the essential barrier function of the bacterial OM."
The architecture of the OmpC-MlaA complex sheds light on the maintenance of outer membrane lipid asymmetry in Escherichia coli.
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MlaA sits entirely within the OM bilayer bound to OmpC and forms a hydrophilic channel gated by a hairpin loop.
"In addition, MlaA forms a hydrophilic channel, likely enabling PL translocation across the OM."
Molecular mechanism of phospholipid transport at the bacterial outer membrane interface.
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MlaC docks on the periplasmic base of MlaA, juxtaposing the MlaA channel with the MlaC lipid-binding cavity; MlaC binding opens the MlaA channel; cryo-EM of OmpC-MlaA-MlaC.
"Here, we biochemically and structurally characterize the MlaA-MlaC transient complex."
Disruption of lipid homeostasis in the Gram-negative cell envelope activates a novel cell death pathway.
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The dominant mlaA* allele increases OM permeability, LPS levels and stationary-phase death.
"a dominant mutation (designated mlaA*, maintenance of lipid asymmetry) that alters MlaA, a lipoprotein that removes phospholipids from the outer leaflet of the OM of Escherichia coli, increases OM permeability, lipopolysaccharide levels, drug sensitivity, and cell death in stationary phase"
Structure of the MlaC-MlaD complex reveals molecular basis of periplasmic phospholipid transport.
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In vitro reconstitution with MlaA-containing donor proteoliposomes, MlaC and MlaFEDB acceptor proteoliposomes supports MlaC-mediated lipid movement from MlaA-containing membranes.
"Readout of transport is reported by the reduction of quenching of NBD labelled phosphatidyl glycerol (PE) by Rhodamine-PE after transport from donor MlaA containing proteoliposomes to acceptor MlaFEDB proteoliposomes by the MlaC chaperone."
ATP disrupts lipid-binding equilibrium to drive retrograde transport critical for bacterial outer membrane asymmetry.
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Reconstitution establishes ATP-driven retrograde phospholipid transport by the OmpC-Mla system (context for MlaA's role).
"ATP binding and/or hydrolysis shift this equilibrium to ultimately drive retrograde PL transport by the OmpC-Mla system"