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Satoshi Murakami - One of the best experts on this subject based on the ideXlab platform.
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crystal structure of tripartite type abc transporter macb from acinetobacter baumannii
Nature Communications, 2017Co-Authors: Ui Okada, Hendrik W. Van Veen, Arthur Neuberger, Eiki Yamashita, Mayu Morimoto, Satoshi MurakamiAbstract:The MacA-MacB-TolC tripartite complex is a transmembrane machine that spans both plasma membrane and outer membrane and actively extrudes substrates, including macrolide antibiotics, virulence factors, peptides and cell envelope precursors. These transport activities are driven by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. Here, we present the crystal structure of MacB at 3.4-A resolution. MacB forms a dimer in which each protomer contains a nucleotide-binding domain and four transmembrane helices that protrude in the periplasm into a binding domain for interaction with the membrane fusion protein MacA. MacB represents an ABC transporter in pathogenic microorganisms with unique structural features.
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structure of the macab tolc abc type tripartite multidrug efflux pump
Nature microbiology, 2017Co-Authors: A W P Fitzpatrick, Salome Llabres, Arthur Neuberger, James N Blaza, Ui Okada, Satoshi Murakami, Hendrik W Van Veen, Ulrich Zachariae, Sjors H W Scheres, Ben F LuisiAbstract:The MacA–MacB–TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism. Cryo-electron microscopy of the tripartite MacA–MacB–TolC multidrug transporter.
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structure of the macab tolc abc type tripartite multidrug efflux pump
Nature microbiology, 2017Co-Authors: A W P Fitzpatrick, Hendrik W. Van Veen, Salome Llabres, Arthur Neuberger, James N Blaza, Ui Okada, Satoshi Murakami, Ulrich Zachariae, Xiao Chen Bai, Sjors H W ScheresAbstract:The MacA-MacB-TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism.
Ui Okada - One of the best experts on this subject based on the ideXlab platform.
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crystal structure of tripartite type abc transporter macb from acinetobacter baumannii
Nature Communications, 2017Co-Authors: Ui Okada, Hendrik W. Van Veen, Arthur Neuberger, Eiki Yamashita, Mayu Morimoto, Satoshi MurakamiAbstract:The MacA-MacB-TolC tripartite complex is a transmembrane machine that spans both plasma membrane and outer membrane and actively extrudes substrates, including macrolide antibiotics, virulence factors, peptides and cell envelope precursors. These transport activities are driven by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. Here, we present the crystal structure of MacB at 3.4-A resolution. MacB forms a dimer in which each protomer contains a nucleotide-binding domain and four transmembrane helices that protrude in the periplasm into a binding domain for interaction with the membrane fusion protein MacA. MacB represents an ABC transporter in pathogenic microorganisms with unique structural features.
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structure of the macab tolc abc type tripartite multidrug efflux pump
Nature microbiology, 2017Co-Authors: A W P Fitzpatrick, Salome Llabres, Arthur Neuberger, James N Blaza, Ui Okada, Satoshi Murakami, Hendrik W Van Veen, Ulrich Zachariae, Sjors H W Scheres, Ben F LuisiAbstract:The MacA–MacB–TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism. Cryo-electron microscopy of the tripartite MacA–MacB–TolC multidrug transporter.
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structure of the macab tolc abc type tripartite multidrug efflux pump
Nature microbiology, 2017Co-Authors: A W P Fitzpatrick, Hendrik W. Van Veen, Salome Llabres, Arthur Neuberger, James N Blaza, Ui Okada, Satoshi Murakami, Ulrich Zachariae, Xiao Chen Bai, Sjors H W ScheresAbstract:The MacA-MacB-TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism.
Hendrik W. Van Veen - One of the best experts on this subject based on the ideXlab platform.
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crystal structure of tripartite type abc transporter macb from acinetobacter baumannii
Nature Communications, 2017Co-Authors: Ui Okada, Hendrik W. Van Veen, Arthur Neuberger, Eiki Yamashita, Mayu Morimoto, Satoshi MurakamiAbstract:The MacA-MacB-TolC tripartite complex is a transmembrane machine that spans both plasma membrane and outer membrane and actively extrudes substrates, including macrolide antibiotics, virulence factors, peptides and cell envelope precursors. These transport activities are driven by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. Here, we present the crystal structure of MacB at 3.4-A resolution. MacB forms a dimer in which each protomer contains a nucleotide-binding domain and four transmembrane helices that protrude in the periplasm into a binding domain for interaction with the membrane fusion protein MacA. MacB represents an ABC transporter in pathogenic microorganisms with unique structural features.
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structure of the macab tolc abc type tripartite multidrug efflux pump
Nature microbiology, 2017Co-Authors: A W P Fitzpatrick, Hendrik W. Van Veen, Salome Llabres, Arthur Neuberger, James N Blaza, Ui Okada, Satoshi Murakami, Ulrich Zachariae, Xiao Chen Bai, Sjors H W ScheresAbstract:The MacA-MacB-TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism.
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MacB ABC Transporter Is a Dimer Whose ATPase Activity and Macrolide-binding Capacity Are Regulated by the Membrane Fusion Protein MacA
The Journal of biological chemistry, 2008Co-Authors: Hong-ting Victor Lin, Vassiliy N. Bavro, Nelson P. Barrera, Helen M. Frankish, Saroj Velamakanni, Hendrik W. Van Veen, Carol V. Robinson, M. Ines Borges-walmsley, Adrian R. WalmsleyAbstract:Gram-negative bacteria utilize specialized machinery to translocate drugs and protein toxins across the inner and outer membranes, consisting of a tripartite complex composed of an inner membrane secondary or primary active transporter (IMP), a periplasmic membrane fusion protein, and an outer membrane channel. We have investigated the assembly and function of the MacAB/TolC system that confers resistance to macrolides in Escherichia coli. The membrane fusion protein MacA not only stabilizes the tripartite assembly by interacting with both the inner membrane protein MacB and the outer membrane protein TolC, but also has a role in regulating the function of MacB, apparently increasing its affinity for both erythromycin and ATP. Analysis of the kinetic behavior of ATP hydrolysis indicated that MacA promotes and stabilizes the ATP-binding form of the MacB transporter. For the first time, we have established unambiguously the dimeric nature of a noncanonic ABC transporter, MacB that has an N-terminal nucleotide binding domain, by means of nondissociating mass spectrometry, analytical ultracentrifugation, and atomic force microscopy. Structural studies of ABC transporters indicate that ATP is bound between a pair of nucleotide binding domains to stabilize a conformation in which the substrate-binding site is outward-facing. Consequently, our data suggest that in the presence of ATP the same conformation of MacB is promoted and stabilized by MacA. Thus, MacA would facilitate the delivery of drugs by MacB to TolC by enhancing the binding of drugs to it and inducing a conformation of MacB that is primed and competent for binding TolC. Our structural studies are an important first step in understanding how the tripartite complex is assembled.
Arthur Neuberger - One of the best experts on this subject based on the ideXlab platform.
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crystal structure of tripartite type abc transporter macb from acinetobacter baumannii
Nature Communications, 2017Co-Authors: Ui Okada, Hendrik W. Van Veen, Arthur Neuberger, Eiki Yamashita, Mayu Morimoto, Satoshi MurakamiAbstract:The MacA-MacB-TolC tripartite complex is a transmembrane machine that spans both plasma membrane and outer membrane and actively extrudes substrates, including macrolide antibiotics, virulence factors, peptides and cell envelope precursors. These transport activities are driven by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. Here, we present the crystal structure of MacB at 3.4-A resolution. MacB forms a dimer in which each protomer contains a nucleotide-binding domain and four transmembrane helices that protrude in the periplasm into a binding domain for interaction with the membrane fusion protein MacA. MacB represents an ABC transporter in pathogenic microorganisms with unique structural features.
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structure of the macab tolc abc type tripartite multidrug efflux pump
Nature microbiology, 2017Co-Authors: A W P Fitzpatrick, Salome Llabres, Arthur Neuberger, James N Blaza, Ui Okada, Satoshi Murakami, Hendrik W Van Veen, Ulrich Zachariae, Sjors H W Scheres, Ben F LuisiAbstract:The MacA–MacB–TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism. Cryo-electron microscopy of the tripartite MacA–MacB–TolC multidrug transporter.
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structure of the macab tolc abc type tripartite multidrug efflux pump
Nature microbiology, 2017Co-Authors: A W P Fitzpatrick, Hendrik W. Van Veen, Salome Llabres, Arthur Neuberger, James N Blaza, Ui Okada, Satoshi Murakami, Ulrich Zachariae, Xiao Chen Bai, Sjors H W ScheresAbstract:The MacA-MacB-TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism.
Vassilis Koronakis - One of the best experts on this subject based on the ideXlab platform.
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antibiotic resistance mediated by the macb abc transporter family a structural and functional perspective
Frontiers in Microbiology, 2018Co-Authors: Nicholas P Greene, Eliseege Kaplan, A Crow, Vassilis KoronakisAbstract:The MacB ABC transporter forms a tripartite efflux pump with the MacA adaptor protein and TolC outer membrane exit duct to expel antibiotics and export virulence factors from Gram-negative bacteria. Here, we review recent structural and functional data on MacB and its homologs. MacB has a fold that is distinct from other structurally characterized ABC transporters and uses a unique molecular mechanism termed mechanotransmission. Unlike other bacterial ABC transporters, MacB does not transport substrates across the inner membrane in which it is based, but instead couples cytoplasmic ATP hydrolysis with transmembrane conformational changes that are used to perform work in the extra-cytoplasmic space. In the MacAB-TolC tripartite pump, mechanotransmission drives efflux of antibiotics and export of a protein toxin from the periplasmic space via the TolC exit duct. Homologous tripartite systems from pathogenic bacteria similarly export protein-like signaling molecules, virulence factors and siderophores. In addition, many MacB-like ABC transporters do not form tripartite pumps, but instead operate in diverse cellular processes including antibiotic sensing, cell division and lipoprotein trafficking.
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structure and mechanotransmission mechanism of the macb abc transporter superfamily
Proceedings of the National Academy of Sciences of the United States of America, 2017Co-Authors: A Crow, Nicholas P Greene, Eliseege Kaplan, Vassilis KoronakisAbstract:MacB is an ABC transporter that collaborates with the MacA adaptor protein and TolC exit duct to drive efflux of antibiotics and enterotoxin STII out of the bacterial cell. Here we present the structure of ATP-bound MacB and reveal precise molecular details of its mechanism. The MacB transmembrane domain lacks a central cavity through which substrates could be passed, but instead conveys conformational changes from one side of the membrane to the other, a process we term mechanotransmission. Comparison of ATP-bound and nucleotide-free states reveals how reversible dimerization of the nucleotide binding domains drives opening and closing of the MacB periplasmic domains via concerted movements of the second transmembrane segment and major coupling helix. We propose that the assembled tripartite pump acts as a molecular bellows to propel substrates through the TolC exit duct, driven by MacB mechanotransmission. Homologs of MacB that do not form tripartite pumps, but share structural features underpinning mechanotransmission, include the LolCDE lipoprotein trafficking complex and FtsEX cell division signaling protein. The MacB architecture serves as the blueprint for understanding the structure and mechanism of an entire ABC transporter superfamily and the many diverse functions it supports.