Activating Compound | Comment | Organism | Structure |
---|---|---|---|
additional information | ATPase activity is substantially higher with the full complex | Escherichia coli | |
additional information | ATPase activity is substantially higher with the full complex | Pseudomonas aeruginosa | |
additional information | ATPase activity is substantially higher with the full complex | Neisseria meningitidis serogroup B / serotype 15 | |
novobiocin | LptB2FG activity and subsequent LPS transport are further enhanced in the presence of the antibiotic novobiocin, a hydrophobic DNA gyrase inhibitor | Pseudomonas aeruginosa | |
novobiocin | LptB2FG activity and subsequent LPS transport are further enhanced in the presence of the antibiotic novobiocin, a hydrophobic DNA gyrase inhibitor | Neisseria meningitidis serogroup B / serotype 15 | |
novobiocin | LptB2FG activity and subsequent LPS transport are further enhanced in the presence of the antibiotic novobiocin, a hydrophobic DNA gyrase inhibitor. Novobiocin binds to the Q-loop and directly interacts with F90 and R91, strongly indicating that LptF/G's effect on LptB ATPase activity is mediated directly through their coupling interaction | Escherichia coli |
Crystallization (Comment) | Organism |
---|---|
analysis of the crystal structures of the LptB2FG tetramer | Escherichia coli |
analysis of the crystal structures of the LptB2FG tetramer | Pseudomonas aeruginosa |
analysis of the crystal structures of the LptB2FG tetramer | Neisseria meningitidis serogroup B / serotype 15 |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
additional information | the LptB2FG complex interacts with the other IM-bound subunit, LptC, and influences LPS extraction. LptC reduces the ATPase of the activity of the complex in vitro | Escherichia coli | |
additional information | the LptB2FG complex interacts with the other IM-bound subunit, LptC, and influences LPS extraction. LptC reduces the ATPase of the activity of the complex in vitro | Neisseria meningitidis serogroup B / serotype 15 | |
additional information | the LptB2FG complex interacts with the other IM-bound subunit, LptC, and influences LPS extraction. LptC reduces the ATPase of the activity of the complex in vitro | Pseudomonas aeruginosa |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
inner membrane | - |
Escherichia coli | - |
- |
inner membrane | - |
Pseudomonas aeruginosa | - |
- |
inner membrane | - |
Neisseria meningitidis serogroup B / serotype 15 | - |
- |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Escherichia coli | |
Mg2+ | required | Pseudomonas aeruginosa | |
Mg2+ | required | Neisseria meningitidis serogroup B / serotype 15 |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + H2O + lipopolysaccharide[side 1] | Escherichia coli | - |
ADP + phosphate + lipopolysaccharide[side 2] | - |
? | |
ATP + H2O + lipopolysaccharide[side 1] | Pseudomonas aeruginosa | - |
ADP + phosphate + lipopolysaccharide[side 2] | - |
? | |
ATP + H2O + lipopolysaccharide[side 1] | Neisseria meningitidis serogroup B / serotype 15 | - |
ADP + phosphate + lipopolysaccharide[side 2] | - |
? | |
ATP + H2O + lipopolysaccharide[side 1] | Neisseria meningitidis serogroup B / serotype 15 H44/76 | - |
ADP + phosphate + lipopolysaccharide[side 2] | - |
? | |
additional information | Escherichia coli | the Lpt (LPS transport) system forms a continuous protein bridge across the inner membrane, periplasm and outer membrane. LptB, LptG, and LptF extract LPS (lipopolysaccharide) from the inner leaflet of the IM (inner membrane) through an ATPase-dependent mechanism | ? | - |
? | |
additional information | Pseudomonas aeruginosa | the Lpt (LPS transport) system forms a continuous protein bridge across the inner membrane, periplasm and outer membrane. LptB, LptG, and LptF extract LPS (lipopolysaccharide) from the inner leaflet of the IM (inner membrane) through an ATPase-dependent mechanism | ? | - |
? | |
additional information | Neisseria meningitidis serogroup B / serotype 15 | the Lpt (LPS transport) system forms a continuous protein bridge across the inner membrane, periplasm and outer membrane. LptB, LptG, and LptF extract LPS (lipopolysaccharide) from the inner leaflet of the IM (inner membrane) through an ATPase-dependent mechanism | ? | - |
? | |
additional information | Neisseria meningitidis serogroup B / serotype 15 H44/76 | the Lpt (LPS transport) system forms a continuous protein bridge across the inner membrane, periplasm and outer membrane. LptB, LptG, and LptF extract LPS (lipopolysaccharide) from the inner leaflet of the IM (inner membrane) through an ATPase-dependent mechanism | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | P0A9V1 | - |
- |
Neisseria meningitidis serogroup B / serotype 15 | E6MYT4 | - |
- |
Neisseria meningitidis serogroup B / serotype 15 H44/76 | E6MYT4 | - |
- |
Pseudomonas aeruginosa | A0A071L2Z5 | - |
- |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
ATP + H2O + lipopolysaccharide[side 1] = ADP + phosphate + lipopolysaccharide[side 2] | LptB2FG tetramer mechanism: 1. Resting: the LptB nucleotide-binding sites are unoccupied, and the LptF/G cavity is oriented inwards. 2. Open: ATP binds LptB, inducing the LptF/G cavity to open away from the IM, and receives the Lipid A moiety of LPS, which is still embedded in the IM. 3. Close: LptB hydrolyzes ATP, inducing the LptF/G cavity to close again. LPS is forced out of the IM into the periplasm | Escherichia coli | |
ATP + H2O + lipopolysaccharide[side 1] = ADP + phosphate + lipopolysaccharide[side 2] | LptB2FG tetramer mechanism: 1. Resting: the LptB nucleotide-binding sites are unoccupied, and the LptF/G cavity is oriented inwards. 2. Open: ATP binds LptB, inducing the LptF/G cavity to open away from the IM, and receives the Lipid A moiety of LPS, which is still embedded in the IM. 3. Close: LptB hydrolyzes ATP, inducing the LptF/G cavity to close again. LPS is forced out of the IM into the periplasm | Pseudomonas aeruginosa | |
ATP + H2O + lipopolysaccharide[side 1] = ADP + phosphate + lipopolysaccharide[side 2] | LptB2FG tetramer mechanism: 1. Resting: the LptB nucleotide-binding sites are unoccupied, and the LptF/G cavity is oriented inwards. 2. Open: ATP binds LptB, inducing the LptF/G cavity to open away from the IM, and receives the Lipid A moiety of LPS, which is still embedded in the IM. 3. Close: LptB hydrolyzes ATP, inducing the LptF/G cavity to close again. LPS is forced out of the IM into the periplasm | Neisseria meningitidis serogroup B / serotype 15 |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + H2O + lipopolysaccharide[side 1] | - |
Escherichia coli | ADP + phosphate + lipopolysaccharide[side 2] | - |
? | |
ATP + H2O + lipopolysaccharide[side 1] | - |
Pseudomonas aeruginosa | ADP + phosphate + lipopolysaccharide[side 2] | - |
? | |
ATP + H2O + lipopolysaccharide[side 1] | - |
Neisseria meningitidis serogroup B / serotype 15 | ADP + phosphate + lipopolysaccharide[side 2] | - |
? | |
ATP + H2O + lipopolysaccharide[side 1] | - |
Neisseria meningitidis serogroup B / serotype 15 H44/76 | ADP + phosphate + lipopolysaccharide[side 2] | - |
? | |
additional information | the Lpt (LPS transport) system forms a continuous protein bridge across the inner membrane, periplasm and outer membrane. LptB, LptG, and LptF extract LPS (lipopolysaccharide) from the inner leaflet of the IM (inner membrane) through an ATPase-dependent mechanism | Escherichia coli | ? | - |
? | |
additional information | the Lpt (LPS transport) system forms a continuous protein bridge across the inner membrane, periplasm and outer membrane. LptB, LptG, and LptF extract LPS (lipopolysaccharide) from the inner leaflet of the IM (inner membrane) through an ATPase-dependent mechanism | Pseudomonas aeruginosa | ? | - |
? | |
additional information | the Lpt (LPS transport) system forms a continuous protein bridge across the inner membrane, periplasm and outer membrane. LptB, LptG, and LptF extract LPS (lipopolysaccharide) from the inner leaflet of the IM (inner membrane) through an ATPase-dependent mechanism | Neisseria meningitidis serogroup B / serotype 15 | ? | - |
? | |
additional information | the Lpt (LPS transport) system forms a continuous protein bridge across the inner membrane, periplasm and outer membrane. LptB, LptG, and LptF extract LPS (lipopolysaccharide) from the inner leaflet of the IM (inner membrane) through an ATPase-dependent mechanism | Neisseria meningitidis serogroup B / serotype 15 H44/76 | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
lptB | - |
Escherichia coli |
lptB | - |
Pseudomonas aeruginosa |
lptB | - |
Neisseria meningitidis serogroup B / serotype 15 |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | - |
Escherichia coli | |
ATP | - |
Pseudomonas aeruginosa | |
ATP | - |
Neisseria meningitidis serogroup B / serotype 15 |
Organism | Comment | Expression |
---|---|---|
Escherichia coli | the C-term LptC mutation reduces the stability of the overall LptB2FGC complex, so increased LptB expression compensates by shifting the binding equilibrium in favor of the LptB2FG complex | up |
Pseudomonas aeruginosa | the C-term LptC mutation reduces the stability of the overall LptB2FGC complex, so increased LptB expression compensates by shifting the binding equilibrium in favor of the LptB2FG complex | up |
Neisseria meningitidis serogroup B / serotype 15 | the C-term LptC mutation reduces the stability of the overall LptB2FGC complex, so increased LptB expression compensates by shifting the binding equilibrium in favor of the LptB2FG complex | up |
General Information | Comment | Organism |
---|---|---|
evolution | LptB2FG represents a third distinct type of ABC transporter, deemed type-III | Escherichia coli |
evolution | LptB2FG represents a third distinct type of ABC transporter, deemed type-III | Pseudomonas aeruginosa |
evolution | LptB2FG represents a third distinct type of ABC transporter, deemed type-III | Neisseria meningitidis serogroup B / serotype 15 |
malfunction | the C-term LptC mutation reduces the stability of the overall LptB2FGC complex, so increased LptB expression compensates by shifting the binding equilibrium in favor of the LptB2FG complex | Escherichia coli |
malfunction | the C-term LptC mutation reduces the stability of the overall LptB2FGC complex, so increased LptB expression compensates by shifting the binding equilibrium in favor of the LptB2FG complex | Pseudomonas aeruginosa |
malfunction | the C-term LptC mutation reduces the stability of the overall LptB2FGC complex, so increased LptB expression compensates by shifting the binding equilibrium in favor of the LptB2FG complex | Neisseria meningitidis serogroup B / serotype 15 |
additional information | identification of the specific subunit-to-subunit interactions that make the continuous transport of LPS from the cytoplasm to the exterior of the outer membrane by Lpt systems possible. The Lpt system is an oligomeric complex consisting of Lpt proteins A through G. The membrane-bound LptB, F, G and C subunits are connected to the LptD/E heterodimer in the OM by periplasmic LptA. LptB's catalytic activity couples to the LptF/G heterodimer's extraction of LPS like other ABC transporters, wherein the coupling helices of the TMD interact with the variable Q-loop of the NBD. Structural comparison of ATP-and ADP-bound LptB shows that ATP binding, hydrolysis and release induce conformational changes in the Q-loop region, mediated predominantly by two conserved residues (F90 and R91). LptC may be important to the efficient and stable assembly of the LptB2FG complex, in addition to directly transporting LPS | Escherichia coli |
additional information | identification of the specific subunit-to-subunit interactions that make the continuous transport of LPS from the cytoplasm to the exterior of the outer membrane by Lpt systems possible. The Lpt system is an oligomeric complex consisting of Lpt proteins A through G. The membrane-bound LptB, F, G and C subunits are connected to the LptD/E heterodimer in the OM by periplasmic LptA. LptC may be important to the efficient and stable assembly of the LptB2FG complex, in addition to directly transporting LPS | Pseudomonas aeruginosa |
additional information | identification of the specific subunit-to-subunit interactions that make the continuous transport of LPS from the cytoplasm to the exterior of the outer membrane by Lpt systems possible. The Lpt system is an oligomeric complex consisting of Lpt proteins A through G. The membrane-bound LptB, F, G and C subunits are connected to the LptD/E heterodimer in the OM by periplasmic LptA. LptC may be important to the efficient and stable assembly of the LptB2FG complex, in addition to directly transporting LPS | Neisseria meningitidis serogroup B / serotype 15 |
physiological function | Gram-negative bacteria have a dense outer membrane (OM) coating of lipopolysaccharides, which is essential to their survival. This coating is assembled by the LPS (lipopolysaccharide) transport (Lpt) system, a coordinated seven-subunit protein complex that spans the cellular envelope. LPS transport is driven by an ATPase-dependent mechanism dubbed the protein-bridge PEZ model, whereby a continuous stream of LPS molecules is pushed from subunit to subunit. The Lpt subunits form a continuous complex from the inner membrane (IM) to the OM and LPS is propelled along it continuously by the ATPase activity of LptB. Subunit-scale mechanisms of LPS transport include the novel ABC-like mechanism of the LptB2FG subcomplex and the lateral insertion of LPS into the OM by LptD/E, overview. The tightly regulated interactions between these connected subcomplexes suggest a pathway that can react dynamically to membrane stress and may prove to be a valuable target for new antibiotic therapies for Gram-negative pathogens. LPS is synthesized at the cytoplasmic side of the IM before it is transported to the OM. The LptB2FG tetramer extracts LPS from the outer leaflet of the IM and provides the energy to drive LPS transport through an ATPase-dependent mechanism, the LptB2FG complex drives LPS extraction from the IM to the periplasm | Escherichia coli |
physiological function | Gram-negative bacteria have a dense outer membrane (OM) coating of lipopolysaccharides, which is essential to their survival. This coating is assembled by the LPS (lipopolysaccharide) transport (Lpt) system, a coordinated seven-subunit protein complex that spans the cellular envelope. LPS transport is driven by an ATPase-dependent mechanism dubbed the protein-bridge PEZ model, whereby a continuous stream of LPS molecules is pushed from subunit to subunit. The Lpt subunits form a continuous complex from the inner membrane (IM) to the OM and LPS is propelled along it continuously by the ATPase activity of LptB. Subunit-scale mechanisms of LPS transport include the novel ABC-like mechanism of the LptB2FG subcomplex and the lateral insertion of LPS into the OM by LptD/E, overview. The tightly regulated interactions between these connected subcomplexes suggest a pathway that can react dynamically to membrane stress and may prove to be a valuable target for new antibiotic therapies for Gram-negative pathogens. LPS is synthesized at the cytoplasmic side of the IM before it is transported to the OM. The LptB2FG tetramer extracts LPS from the outer leaflet of the IM and provides the energy to drive LPS transport through an ATPase-dependent mechanism. the LptB2FG complex drives LPS extraction from the IM to the periplasm | Pseudomonas aeruginosa |
physiological function | Gram-negative bacteria have a dense outer membrane (OM) coating of lipopolysaccharides, which is essential to their survival. This coating is assembled by the LPS (lipopolysaccharide) transport (Lpt) system, a coordinated seven-subunit protein complex that spans the cellular envelope. LPS transport is driven by an ATPase-dependent mechanism dubbed the protein-bridge PEZ model, whereby a continuous stream of LPS molecules is pushed from subunit to subunit. The Lpt subunits form a continuous complex from the inner membrane (IM) to the OM and LPS is propelled along it continuously by the ATPase activity of LptB. Subunit-scale mechanisms of LPS transport include the novel ABC-like mechanism of the LptB2FG subcomplex and the lateral insertion of LPS into the OM by LptD/E, overview. The tightly regulated interactions between these connected subcomplexes suggest a pathway that can react dynamically to membrane stress and may prove to be a valuable target for new antibiotic therapies for Gram-negative pathogens. LPS is synthesized at the cytoplasmic side of the IM before it is transported to the OM. The LptB2FG tetramer extracts LPS from the outer leaflet of the IM and provides the energy to drive LPS transport through an ATPase-dependent mechanism. the LptB2FG complex drives LPS extraction from the IM to the periplasm | Neisseria meningitidis serogroup B / serotype 15 |