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Cottom CO, Stephenson R, Ricci D, Yang L, Gumbart JC, Noinaj N. Structural characterization of the POTRA domains from A. baumannii reveals new conformations in BamA. Structure 2024:S0969-2126(24)00330-7. [PMID: 39293443 DOI: 10.1016/j.str.2024.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 07/17/2024] [Accepted: 08/22/2024] [Indexed: 09/20/2024]
Abstract
Recent studies have demonstrated BamA, the central component of the β-barrel assembly machinery (BAM), as an important therapeutic target to combat infections caused by Acinetobacter baumannii and other Gram-negative pathogens. Homology modeling indicates BamA in A. baumannii consists of five polypeptide transport-associated (POTRA) domains and a β-barrel membrane domain. We characterized the POTRA domains of BamA from A. baumannii in solution using size-exclusion chromatography small angle X-ray scattering (SEC-SAXS) analysis and determined crystal structures in two conformational states that are drastically different than those previously observed in BamA from other bacteria, indicating that the POTRA domains are even more conformationally dynamic than has been observed previously. Molecular dynamics simulations of the POTRA domains from A. baumannii and Escherichia coli allowed us to identify key structural features that contribute to the observed novel states. Together, these studies expand on our current understanding of the conformational plasticity within BamA across differing bacterial species.
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Affiliation(s)
| | - Robert Stephenson
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Dante Ricci
- Achaogen, Inc., South San Francisco, CA, USA
| | - Lixinhao Yang
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, USA
| | - James C Gumbart
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, USA; School of Physics, Georgia Institute of Technology, Atlanta, GA, USA
| | - Nicholas Noinaj
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA; Markey Center for Structural Biology, Purdue University, West Lafayette, IN, USA; Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA.
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2
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Hessami A, Mogharari Z, Rahim F, Khalesi B, Jamal Nassrullah O, Reza Rahbar M, Khalili S, Jahangiri A. In silico design of a novel hybrid epitope-based antigen harboring highly exposed immunogenic peptides of BamA, OmpA, and Omp34 against Acinetobacter baumannii. Int Immunopharmacol 2024; 142:113066. [PMID: 39241518 DOI: 10.1016/j.intimp.2024.113066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 08/07/2024] [Accepted: 08/30/2024] [Indexed: 09/09/2024]
Abstract
Acinetobacter baumannii, is among the highest priority bacteria according to the WHO categorization which necessitate the exploration of alternative strategies such as vaccination. OmpA, BamA, and Omp34 are assigned as appropriate antigens to serve in vaccine development against this pathogen. Experimentally validated exposed epitopes of OmpA and Omp34 along with selected exposed epitopes predicted by an integrative in silico approach were represented by the barrel domain of BamA as a scaffold. Among the 8 external loops of BamA, 5 loops were replaced with selected loops of OmpA and Omp34. The designed antigen was analyzed regarding the physicochemical properties, antigenicity, epitope retrieval, topology, structure, and safety. BamA is a two-domain OMP with a 16-stranded barrel in which L4, L6, and L7 were the longest loops of BamA in order. The designed antigen consisted of 478 amino acids with antigen probability of 0.7793. The novel antigen was a 16-stranded barrel. No identical 8-meric peptides were found in the human proteome against the designed antigen sequence. The designed construct was safe regarding the allergenicity, toxicity, and human proteome reactivity. The designed antigen could develop higher protection against A. baumannii in comparison to either OmpA, BamA, or Omp34 alone.
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Affiliation(s)
- Anahita Hessami
- School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Fatemeh Rahim
- Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares, P.O. Box: 14115-154, Tehran, Iran
| | - Bahman Khalesi
- Department of Research and Production of Poultry Viral Vaccine, Razi Vaccine and Serum Research Institute, Agricultural Research Education and Extension Organization, Karaj, Iran
| | | | - Mohammad Reza Rahbar
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Saeed Khalili
- Department of Biology Sciences, Shahid Rajaee Teacher Training University, Tehran, Iran
| | - Abolfazl Jahangiri
- Applied Microbiology Research Center, Biomedicine Technologies Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.
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3
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Panji Z, Nadoushan MJ, Fekrirad Z, Rasooli I. Modulation with anti-Oma87 antibodies of cytotoxicity, adherence, and internalization of Acinetobacter baumannii in human cervical carcinoma epithelial cells. APMIS 2024. [PMID: 39223818 DOI: 10.1111/apm.13465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2024] [Accepted: 08/12/2024] [Indexed: 09/04/2024]
Abstract
BamA, an Omp85 superfamily member, is universally conserved and essential for cell viability. Using anti-Oma87 antibodies, we focus on understanding the effect of Oma87 of Acinetobacter baumannii on pathogenicity. Oma87 was expressed, purified, and used to induce anti-Oma87 antibodies in BALB/c mice. Acute toxicity of the protein was evaluated in mice. HeLa cells were infected with both live and killed A. baumannii 19606 and a clinical isolate. The effects of anti-Oma87 sera on A. baumannii adherence, internalization, and proliferation in HeLa cells were studied. The roles of microfilaments and microtubules in A. baumannii invasion were demonstrated by Actin disruption. Reduced bacterial population and biofilm formation were noted. The ability of A. baumannii to provoke autophagy through Oma87 induction leads to incomplete autophagy and potentially facilitates bacterial replication. Actin-mediated uptake, attachment, and invasion demonstrated A. baumannii survival and multiplication within vacuoles in the host cell. The findings underscore the potential of Oma87 as a therapeutic intervention target in infections caused by A. baumannii. This comprehensive analysis contributes valuable information for understanding the virulence mechanisms of A. baumannii, potentially guiding future strategies to combat infections caused by this pathogen.
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Affiliation(s)
- Zahra Panji
- Department of Biology, Shahed University, Tehran, Iran
| | - Mohammadreza Jalali Nadoushan
- Department of Pathology, School of Medicine, Shahed University, Tehran, Iran
- Molecular Microbiology Research Center and Department of Biology, Shahed University, Tehran, Iran
| | | | - Iraj Rasooli
- Department of Biology, Shahed University, Tehran, Iran
- Molecular Microbiology Research Center and Department of Biology, Shahed University, Tehran, Iran
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4
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Yang N, Jin X, Zhu C, Gao F, Weng Z, Du X, Feng G. Subunit vaccines for Acinetobacter baumannii. Front Immunol 2023; 13:1088130. [PMID: 36713441 PMCID: PMC9878323 DOI: 10.3389/fimmu.2022.1088130] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 12/22/2022] [Indexed: 01/15/2023] Open
Abstract
Acinetobacter baumannii is a gram-negative bacterium and a crucial opportunistic pathogen in hospitals. A. baumannii infection has become a challenging problem in clinical practice due to the increasing number of multidrug-resistant strains and their prevalence worldwide. Vaccines are effective tools to prevent and control A. baumannii infection. Many researchers are studying subunit vaccines against A. baumannii. Subunit vaccines have the advantages of high purity, safety, and stability, ease of production, and highly targeted induced immune responses. To date, no A. baumannii subunit vaccine candidate has entered clinical trials. This may be related to the easy degradation of subunit vaccines in vivo and weak immunogenicity. Using adjuvants or delivery vehicles to prepare subunit vaccines can slow down degradation and improve immunogenicity. The common immunization routes include intramuscular injection, subcutaneous injection, intraperitoneal injection and mucosal vaccination. The appropriate immunization method can also enhance the immune effect of subunit vaccines. Therefore, selecting an appropriate adjuvant and immunization method is essential for subunit vaccine research. This review summarizes the past exploration of A. baumannii subunit vaccines, hoping to guide current and future research on these vaccines.
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Affiliation(s)
- Ning Yang
- Department of Respiratory and Critical Care Medicine, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiao Jin
- Department of Respiratory and Critical Care Medicine, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Chenghua Zhu
- Department of Respiratory and Critical Care Medicine, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Fenglin Gao
- Department of Respiratory and Critical Care Medicine, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Zheqi Weng
- The Second Clinical Medical School of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xingran Du
- Department of Infectious Disease, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China,*Correspondence: Xingran Du, ; Ganzhu Feng,
| | - Ganzhu Feng
- Department of Respiratory and Critical Care Medicine, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China,*Correspondence: Xingran Du, ; Ganzhu Feng,
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5
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Plasticity within the barrel domain of BamA mediates a hybrid-barrel mechanism by BAM. Nat Commun 2021; 12:7131. [PMID: 34880256 PMCID: PMC8655018 DOI: 10.1038/s41467-021-27449-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 11/22/2021] [Indexed: 12/26/2022] Open
Abstract
In Gram-negative bacteria, the biogenesis of β-barrel outer membrane proteins is mediated by the β-barrel assembly machinery (BAM). The mechanism employed by BAM is complex and so far- incompletely understood. Here, we report the structures of BAM in nanodiscs, prepared using polar lipids and native membranes, where we observe an outward-open state. Mutations in the barrel domain of BamA reveal that plasticity in BAM is essential, particularly along the lateral seam of the barrel domain, which is further supported by molecular dynamics simulations that show conformational dynamics in BAM are modulated by the accessory proteins. We also report the structure of BAM in complex with EspP, which reveals an early folding intermediate where EspP threads from the underside of BAM and incorporates into the barrel domain of BamA, supporting a hybrid-barrel budding mechanism in which the substrate is folded into the membrane sequentially rather than as a single unit.
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6
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Xiao L, Han L, Li B, Zhang M, Zhou H, Luo Q, Zhang X, Huang Y. Structures of the β-barrel assembly machine recognizing outer membrane protein substrates. FASEB J 2021; 35:e21207. [PMID: 33368572 DOI: 10.1096/fj.202001443rr] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 11/11/2022]
Abstract
β-barrel outer membrane proteins (β-OMPs) play critical roles in nutrition acquisition, protein import/export, and other fundamental biological processes. The assembly of β-OMPs in Gram-negative bacteria is mediated by the β-barrel assembly machinery (BAM) complex, yet its precise mechanism remains elusive. Here, we report two structures of the BAM complex in detergents and in nanodisks, and two crystal structures of the BAM complex with bound substrates. Structural analysis indicates that the membrane compositions surrounding the BAM complex could modulate its overall conformations, indicating low energy barriers between different conformational states and a highly dynamic nature of the BAM complex. Importantly, structures of the BAM complex with bound substrates and the related functional analysis show that the first β-strand of the BamA β-barrel (β1BamA ) in the BAM complex is associated with the last but not the first β-strand of a β-OMP substrate via antiparallel β-strand interactions. These observations are consistent with the β-signal hypothesis during β-OMP biogenesis, and suggest that the β1BamA strand in the BAM complex may interact with the last β-strand of an incoming β-OMP substrate upon their release from the chaperone-bound state.
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Affiliation(s)
- Le Xiao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Long Han
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Bufan Li
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Manfeng Zhang
- Lingnan Guangdong Laboratory of Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Haizhen Zhou
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Qingshan Luo
- Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, China
| | - Xinzheng Zhang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yihua Huang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
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7
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Vieira de Araujo AE, Conde LV, da Silva Junior HC, de Almeida Machado L, Lara FA, Chapeaurouge A, Pauer H, Pires Hardoim CC, Martha Antunes LC, D'Alincourt Carvalho-Assef AP, Moreno Senna JP. Cross-reactivity and immunotherapeutic potential of BamA recombinant protein from Acinetobacter baumannii. Microbes Infect 2021; 23:104801. [PMID: 33582283 DOI: 10.1016/j.micinf.2021.104801] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 01/18/2021] [Accepted: 02/04/2021] [Indexed: 12/18/2022]
Abstract
Acinetobacter baumannii is an important nosocomial pathogen. BamA is a protein that belongs to a complex responsible for organizing the proteins on the bacterial outer membrane. In this work, we aimed to evaluate murine immune responses to BamA recombinant protein (rAbBamA) from A. baumannii in an animal model of infection, and to assess cross-reactivity of this target for the development of anti-A. baumannii vaccines or diagnostics. Immunization of mice with rAbBamA elicited high antibody titers and antibody recognition of native A. baumannii BamA. Immunofluorescence also detected binding to the bacterial surface. After challenge, immunized mice demonstrated a 40% survival increase and better bacterial clearance in kidneys. Immunoblot of anti-rAbBamA against other medically relevant bacteria showed binding to proteins of approximately 35 kDa in Klebsiella pneumoniae and Escherichia coli lysates, primarily identified as OmpA and OmpC, respectively. Altogether, our data show that anti-rAbBamA antibodies provide a protective response against A. baumannii infection in mice. However, the response elicited by immunization with rAbBamA is not completely specific to A. baumannii. Although a broad-spectrum vaccine that protects against various pathogens is an appealing strategy, antibody reactivity against the human microbiota is undesired. In fact, immunization with rAbBamA produced noticeable effects on the gut microbiota. However, the changes elicited were small and non-specific, given that no significant changes in the abundance of Proteobacteria were observed. Overall, rAbBamA is a promising target, but specificity must be considered in the development of immunological tools against A. baumannii.
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Affiliation(s)
- Anna Erika Vieira de Araujo
- Bio-Manguinhos, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, RJ, Brazil; Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, RJ, Brazil.
| | - Luis Vidal Conde
- Bio-Manguinhos, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, RJ, Brazil.
| | | | - Lucas de Almeida Machado
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, RJ, Brazil.
| | - Flavio Alves Lara
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, RJ, Brazil.
| | - Alex Chapeaurouge
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, RJ, Brazil.
| | - Heidi Pauer
- National Institute of Science and Technology of Innovation on Diseases of Neglected Populations, Center for Technological Development in Health, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, Brazil.
| | | | - Luis Caetano Martha Antunes
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, RJ, Brazil; National Institute of Science and Technology of Innovation on Diseases of Neglected Populations, Center for Technological Development in Health, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, Brazil.
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8
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Lundquist K, Billings E, Bi M, Wellnitz J, Noinaj N. The assembly of β-barrel membrane proteins by BAM and SAM. Mol Microbiol 2020; 115:425-435. [PMID: 33314350 DOI: 10.1111/mmi.14666] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 12/11/2020] [Indexed: 12/31/2022]
Abstract
Gram-negative bacteria, mitochondria, and chloroplasts all possess an outer membrane populated with a host of β-barrel outer-membrane proteins (βOMPs). These βOMPs play crucial roles in maintaining viability of their hosts, and therefore, it is essential to understand the biogenesis of this class of membrane proteins. In recent years, significant structural and functional advancements have been made toward elucidating this process, which is mediated by the β-barrel assembly machinery (BAM) in Gram-negative bacteria, and by the sorting and assembly machinery (SAM) in mitochondria. Structures of both BAM and SAM have now been reported, allowing a comparison and dissection of the two machineries, with other studies reporting on functional aspects of each. Together, these new insights provide compelling support for the proposed budding mechanism, where each nascent βOMP forms a hybrid-barrel intermediate with BAM/SAM in route to its biogenesis into the membrane. Here, we will review these recent studies and highlight their contributions toward understanding βOMP biogenesis in Gram-negative bacteria and in mitochondria. We will also weigh the evidence supporting each of the two leading mechanistic models for how BAM/SAM function, and offer an outlook on future studies within the field.
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Affiliation(s)
- Karl Lundquist
- Department of Biological Sciences, Markey Center for Structural Biology, Purdue University, West Lafayette, IN, USA
| | - Evan Billings
- Department of Biological Sciences, Markey Center for Structural Biology, Purdue University, West Lafayette, IN, USA
| | - Maxine Bi
- Department of Biological Sciences, Markey Center for Structural Biology, Purdue University, West Lafayette, IN, USA
| | - James Wellnitz
- Department of Biological Sciences, Markey Center for Structural Biology, Purdue University, West Lafayette, IN, USA
| | - Nicholas Noinaj
- Department of Biological Sciences, Markey Center for Structural Biology, Purdue University, West Lafayette, IN, USA.,Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, USA
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9
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Effects of Pseudomonas aeruginosa on Microglial-Derived Extracellular Vesicle Biogenesis and Composition. Pathogens 2019; 8:pathogens8040297. [PMID: 31847332 PMCID: PMC6963293 DOI: 10.3390/pathogens8040297] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 11/29/2019] [Accepted: 12/10/2019] [Indexed: 12/17/2022] Open
Abstract
The packaging of molecular constituents inside extracellular vesicles (EVs) allows them to participate in intercellular communication and the transfer of biological molecules, however the role of EVs during bacterial infection is poorly understood. The goal of this study was to examine the effects of Pseudomonas aeruginosa (P. aeruginosa) infection on the biogenesis and composition of EVs derived from the mouse microglia cell line, BV-2. BV-2 cells were cultured in exosome-free media and infected with 0, 1.3 × 104, or 2.6 × 104 colony forming units per milliliter P. aeruginosa for 72 h. The results indicated that compared with the control group, BV-2 cell viability significantly decreased after P. aeruginosa infection and BV-2-derived EVs concentration decreased significantly in the P. aeruginosa-infected group. P. aeruginosa infection significantly decreased chemokine ligand 4 messenger RNA in BV-2-derived infected EVs, compared with the control group (p ≤ 0.05). This study also revealed that heat shock protein 70 (p ≤ 0.05) and heat shock protein 90β (p ≤ 0.001) levels of expression within EVs increased after P. aeruginosa infection. EV treatment with EVs derived from P. aeruginosa infection reduced cell viability of BV-2 cells. P. aeruginosa infection alters the expression of specific proteins and mRNA in EVs. Our study suggests that P. aeruginosa infection modulates EV biogenesis and composition, which may influence bacterial pathogenesis and infection.
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Antibiotic treatment modulates protein components of cytotoxic outer membrane vesicles of multidrug-resistant clinical strain, Acinetobacter baumannii DU202. Clin Proteomics 2018; 15:28. [PMID: 30186054 PMCID: PMC6118003 DOI: 10.1186/s12014-018-9204-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 08/16/2018] [Indexed: 12/31/2022] Open
Abstract
Background Outer membrane vesicles (OMVs) of Acinetobacter baumannii are cytotoxic and elicit a potent innate immune response. OMVs were first identified in A. baumannii DU202, an extensively drug-resistant clinical strain. Herein, we investigated protein components of A. baumannii DU202 OMVs following antibiotic treatment by proteogenomic analysis. Methods Purified OMVs from A. baumannii DU202 grown in different antibiotic culture conditions were screened for pathogenic and immunogenic effects, and subjected to quantitative proteomic analysis by one-dimensional electrophoresis and liquid chromatography combined with tandem mass spectrometry (1DE-LC-MS/MS). Protein components modulated by imipenem were identified and discussed. Results OMV secretion was increased > twofold following imipenem treatment, and cytotoxicity toward A549 human lung carcinoma cells was elevated. A total of 277 proteins were identified as components of OMVs by imipenem treatment, among which β-lactamase OXA-23, various proteases, outer membrane proteins, β-barrel assembly machine proteins, peptidyl-prolyl cis–trans isomerases and inherent prophage head subunit proteins were significantly upregulated. Conclusion In vitro stress such as antibiotic treatment can modulate proteome components in A. baumannii OMVs and thereby influence pathogenicity. Electronic supplementary material The online version of this article (10.1186/s12014-018-9204-2) contains supplementary material, which is available to authorized users.
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11
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Abstract
In Gram-negative bacteria, the outer membrane contains primarily β-barrel transmembrane proteins and lipoproteins. The insertion and assembly of β-barrel outer-membrane proteins (OMPs) is mediated by the β-barrel assembly machinery (BAM) complex, the core component of which is the 16-stranded transmembrane β-barrel BamA. Recent studies have indicated a possible role played by the seam between the first and last β-barrel strands of BamA in the OMP insertion process through lateral gating and a destabilized membrane region. In this study, we have determined the stability and dynamics of the lateral gate through over 12.5 μs of equilibrium simulations and 4 μs of free-energy calculations. From the equilibrium simulations, we have identified a persistent kink in the C-terminal strand and observed spontaneous lateral-gate separation in a mimic of the native bacterial outer membrane. Free-energy calculations of lateral gate opening revealed a significantly lower barrier to opening in the C-terminal kinked conformation; mutagenesis experiments confirm the relevance of C-terminal kinking to BamA structure and function.
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12
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Chaturvedi D, Mahalakshmi R. Transmembrane β-barrels: Evolution, folding and energetics. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:2467-2482. [PMID: 28943271 DOI: 10.1016/j.bbamem.2017.09.020] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/16/2017] [Accepted: 09/19/2017] [Indexed: 12/23/2022]
Abstract
The biogenesis of transmembrane β-barrels (outer membrane proteins, or OMPs) is an elaborate multistep orchestration of the nascent polypeptide with translocases, barrel assembly machinery, and helper chaperone proteins. Several theories exist that describe the mechanism of chaperone-assisted OMP assembly in vivo and unassisted (spontaneous) folding in vitro. Structurally, OMPs of bacterial origin possess even-numbered strands, while mitochondrial β-barrels are even- and odd-stranded. Several underlying similarities between prokaryotic and eukaryotic β-barrels and their folding machinery are known; yet, the link in their evolutionary origin is unclear. While OMPs exhibit diversity in sequence and function, they share similar biophysical attributes and structure. Similarly, it is important to understand the intricate OMP assembly mechanism, particularly in eukaryotic β-barrels that have evolved to perform more complex functions. Here, we deliberate known facets of β-barrel evolution, folding, and stability, and attempt to highlight outstanding questions in β-barrel biogenesis and proteostasis.
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Affiliation(s)
- Deepti Chaturvedi
- Molecular Biophysics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal 462066, India.
| | - Radhakrishnan Mahalakshmi
- Molecular Biophysics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research, Bhopal 462066, India.
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13
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Abstract
In Gram-negative bacteria, the biogenesis of β-barrel outer membrane proteins (OMPs) is mediated by the β-barrel assembly machinery (BAM) complex. During the past decade, structural and functional studies have collectively contributed to advancing our understanding of the structure and function of the BAM complex; however, the exact mechanism that is involved remains elusive. In this Progress article, we discuss recent structural studies that have revealed that the accessory proteins may regulate essential unprecedented conformational changes in the core component BamA during function. We also detail the mechanistic insights that have been gained from structural data, mutagenesis studies and molecular dynamics simulations, and explore two emerging models for the BAM-mediated biogenesis of OMPs in bacteria.
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Affiliation(s)
- Nicholas Noinaj
- Markey Center for Structural Biology, Department of Biological Sciences and the Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, Indiana 47907, USA
| | - James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Susan K Buchanan
- National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
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14
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Fielden LF, Kang Y, Newton HJ, Stojanovski D. Targeting mitochondria: how intravacuolar bacterial pathogens manipulate mitochondria. Cell Tissue Res 2016; 367:141-154. [PMID: 27515462 DOI: 10.1007/s00441-016-2475-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 07/07/2016] [Indexed: 02/07/2023]
Abstract
Manipulation of host cell function by bacterial pathogens is paramount for successful invasion and creation of a niche conducive to bacterial replication. Mitochondria play a role in many important cellular processes including energy production, cellular calcium homeostasis, lipid metabolism, haeme biosynthesis, immune signalling and apoptosis. The sophisticated integration of host cell processes by the mitochondrion have seen it emerge as a key target during bacterial infection of human host cells. This review highlights the targeting and interaction of this dynamic organelle by intravacuolar bacterial pathogens and the way that the modulation of mitochondrial function might contribute to pathogenesis.
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Affiliation(s)
- Laura F Fielden
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Yilin Kang
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Hayley J Newton
- Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, VIC, 3000, Australia.
| | - Diana Stojanovski
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, 3010, Australia.
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15
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Han L, Zheng J, Wang Y, Yang X, Liu Y, Sun C, Cao B, Zhou H, Ni D, Lou J, Zhao Y, Huang Y. Structure of the BAM complex and its implications for biogenesis of outer-membrane proteins. Nat Struct Mol Biol 2016; 23:192-6. [PMID: 26900875 DOI: 10.1038/nsmb.3181] [Citation(s) in RCA: 152] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 02/02/2016] [Indexed: 11/09/2022]
Abstract
In Gram-negative bacteria, the assembly of β-barrel outer-membrane proteins (OMPs) requires the β-barrel-assembly machinery (BAM) complex. We determined the crystal structure of the 200-kDa BAM complex from Escherichia coli at 3.55-Å resolution. The structure revealed that the BAM complex assembles into a hat-like shape, in which the BamA β-barrel domain forms the hat's crown embedded in the outer membrane, and its five polypeptide transport-associated (POTRA) domains interact with the four lipoproteins BamB, BamC, BamD and BamE, thus forming the hat's brim in the periplasm. The assembly of the BAM complex creates a ring-like apparatus beneath the BamA β-barrel in the periplasm and a potential substrate-exit pore located at the outer membrane-periplasm interface. The complex structure suggests that the chaperone-bound OMP substrates may feed into the chamber of the ring-like apparatus and insert into the outer membrane via the potential substrate-exit pore in an energy-independent manner.
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Affiliation(s)
- Long Han
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jiangge Zheng
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yan Wang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Xu Yang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yanqing Liu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Chuanqi Sun
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Baohua Cao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Haizhen Zhou
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Dongchun Ni
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Jizhong Lou
- Key Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yongfang Zhao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yihua Huang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
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16
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Oh YJ, Hwang I. Targeting and biogenesis of transporters and channels in chloroplast envelope membranes: Unsolved questions. Cell Calcium 2014; 58:122-30. [PMID: 25465895 DOI: 10.1016/j.ceca.2014.10.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Revised: 10/23/2014] [Accepted: 10/24/2014] [Indexed: 01/10/2023]
Abstract
Chloroplasts produce carbohydrates, hormones, vitamins, amino acids, pigments, nucleotides, ATP, and secondary metabolites. Channels and transporters are required for the movement of molecules across the two chloroplast envelope membranes. These transporters and channel proteins are grouped into two different types, including β-barrel proteins and transmembrane-domain (TMD) containing proteins. Most β-barrel proteins are localized at the outer chloroplast membrane, and TMD-containing proteins are localized at the inner chloroplast membrane. Many of these transporters and channels are encoded by nuclear genes; therefore, they have to be imported into chloroplasts after translation on cytosolic ribosomes. These proteins should have specific targeting signals for their final destination in the chloroplast membrane and for assembly into specific complexes. In this review, we summarize recent progress in the identification, functional characterization, and biogenesis of transporters and channels at the chloroplast envelope membranes, and discuss outstanding questions regarding transporter and channel protein biogenesis.
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Affiliation(s)
- Young Jun Oh
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
| | - Inhwan Hwang
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea; Department Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
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17
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Höhr AIC, Straub SP, Warscheid B, Becker T, Wiedemann N. Assembly of β-barrel proteins in the mitochondrial outer membrane. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:74-88. [PMID: 25305573 DOI: 10.1016/j.bbamcr.2014.10.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 09/25/2014] [Accepted: 10/01/2014] [Indexed: 12/15/2022]
Abstract
Mitochondria evolved through endosymbiosis of a Gram-negative progenitor with a host cell to generate eukaryotes. Therefore, the outer membrane of mitochondria and Gram-negative bacteria contain pore proteins with β-barrel topology. After synthesis in the cytosol, β-barrel precursor proteins are first transported into the mitochondrial intermembrane space. Folding and membrane integration of β-barrel proteins depend on the mitochondrial sorting and assembly machinery (SAM) located in the outer membrane, which is related to the β-barrel assembly machinery (BAM) in bacteria. The SAM complex recognizes β-barrel proteins by a β-signal in the C-terminal β-strand that is required to initiate β-barrel protein insertion into the outer membrane. In addition, the SAM complex is crucial to form membrane contacts with the inner mitochondrial membrane by interacting with the mitochondrial contact site and cristae organizing system (MICOS) and shares a subunit with the endoplasmic reticulum-mitochondria encounter structure (ERMES) that links the outer mitochondrial membrane to the endoplasmic reticulum (ER).
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Affiliation(s)
- Alexandra I C Höhr
- Institut für Biochemie und Molekularbiologie, ZBMZ, Universität Freiburg, 79104 Freiburg, Germany; Fakultät für Biologie, Universität Freiburg, 79104 Freiburg, Germany
| | - Sebastian P Straub
- Institut für Biochemie und Molekularbiologie, ZBMZ, Universität Freiburg, 79104 Freiburg, Germany; Fakultät für Biologie, Universität Freiburg, 79104 Freiburg, Germany
| | - Bettina Warscheid
- BIOSS Centre for Biological Signalling Studies, Universität Freiburg, 79104 Freiburg, Germany; Abteilung Biochemie und Funktionelle Proteomik, Institut für Biologie II, Fakultät für Biologie, Universität Freiburg, 79104 Freiburg, Germany
| | - Thomas Becker
- Institut für Biochemie und Molekularbiologie, ZBMZ, Universität Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Universität Freiburg, 79104 Freiburg, Germany
| | - Nils Wiedemann
- Institut für Biochemie und Molekularbiologie, ZBMZ, Universität Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Universität Freiburg, 79104 Freiburg, Germany.
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18
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Ni D, Wang Y, Yang X, Zhou H, Hou X, Cao B, Lu Z, Zhao X, Yang K, Huang Y. Structural and functional analysis of the β-barrel domain of BamA from Escherichia coli. FASEB J 2014; 28:2677-85. [PMID: 24619089 DOI: 10.1096/fj.13-248450] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In gram-negative bacteria, the assembly of outer membrane proteins (OMPs) requires a β-barrel assembly machinery (BAM) complex, of which BamA is an essential and evolutionarily conserved component. To elucidate the mechanism of BamA-mediated OMP biogenesis, we determined the crystal structure of the C-terminal transmembrane domain of BamA from Escherichia coli (EcBamA) at 2.6 Å resolution. The structure reveals 2 distinct features. First, a portion of the extracellular side of the β barrel is composed of 5 markedly short β strands, and the loops stemming from these β strands form a potential surface cavity, filled by a portion of the L6 loop that includes the conserved VRGF/Y motif found in the Omp85 family. Second, the 4 extracellular loops L3, L4, L6, and L7 of EcBamA form a dome over the barrel, stabilized by a salt-bridge interaction network. Functional data show that hydrophilic-to-hydrophobic mutations of the potential hydrophilic surface cavity and a single Arg547Ala point mutation that may destabilize the dome severely affect the function of EcBamA. Our structure of the EcBamA β barrel and structure-based mutagenesis studies suggest that the transmembrane β strands of OMP substrates may integrate into the outer membrane at the interface of the first and last β strands of the EcBamA barrel, whereas the soluble loops or domains may be transported out of the cell via the hydrophilic surface cavity on dislocation of the VRGF/Y motif of L6. In addition, the dome over the barrel may play an important role in maintaining the efficiency of OMP biogenesis.
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Affiliation(s)
- Dongchun Ni
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; School of Public Health, Tianjin Medical University, Tianjin, China
| | - Yan Wang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China; and
| | - Xu Yang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Haizhen Zhou
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Xiaomin Hou
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Baohua Cao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Zhixin Lu
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species and Department of Chemical Biology, College of Chemistry and Molecular Engineering, and Biodynamic Optical Imaging Center, Peking University, Beijing, China
| | - Xinsheng Zhao
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species and Department of Chemical Biology, College of Chemistry and Molecular Engineering, and Biodynamic Optical Imaging Center, Peking University, Beijing, China
| | - Kun Yang
- School of Public Health, Tianjin Medical University, Tianjin, China
| | - Yihua Huang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China;
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19
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Cavalier-Smith T. Symbiogenesis: Mechanisms, Evolutionary Consequences, and Systematic Implications. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2013. [DOI: 10.1146/annurev-ecolsys-110411-160320] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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20
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Noinaj N, Kuszak AJ, Gumbart JC, Lukacik P, Chang H, Easley NC, Lithgow T, Buchanan SK. Structural insight into the biogenesis of β-barrel membrane proteins. Nature 2013; 501:385-90. [PMID: 23995689 PMCID: PMC3779476 DOI: 10.1038/nature12521] [Citation(s) in RCA: 330] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 08/01/2013] [Indexed: 11/17/2022]
Abstract
β-barrel membrane proteins are essential for nutrient import, signaling, motility, and survival. In Gram-negative bacteria, the β-barrel assembly machinery (BAM) complex is responsible for the biogenesis of β-barrel membrane proteins, with homologous complexes found in mitochondria and chloroplasts. Here we describe the structure of BamA, the central and essential component of the BAM complex, from two species of bacteria: Neisseria gonorrhoeae and Haemophilus ducreyi. BamA consists of a large periplasmic domain attached to a 16-strand transmembrane β-barrel domain. Three structural features speak to the mechanism by which BamA catalyzes β-barrel assembly. First, the interior cavity is accessible in one BamA structure and conformationally closed in the other. Second, an exterior rim of the β-barrel has a distinctly narrowed hydrophobic surface, locally destabilizing the outer membrane. And third, the β-barrel can undergo lateral opening, evocatively suggesting a route from the interior cavity in BamA into the outer membrane.
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Affiliation(s)
- Nicholas Noinaj
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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21
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Yuan B, Cheng A, Wang M. Polysaccharide export outer membrane proteins in Gram-negative bacteria. Future Microbiol 2013; 8:525-35. [DOI: 10.2217/fmb.13.13] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Polysaccharide export outer membrane proteins of Gram-negative bacteria are involved in the export of polysaccharides across the outer membrane. The mechanisms of polysaccharide export across the outer membrane in Gram-negative bacteria are not yet completely clear. However, the mechanisms of polysaccharide assembly in Escherichia coli have been intensively investigated. Here, we mainly review the current understanding of the assembly mechanisms of group 1 capsular polysaccharide, group 2 capsular polysaccharide and lipopolysaccharide of E. coli, and the current structures and interactions of some polysaccharide export outer membrane proteins with other proteins involved in polysaccharide export in Gram-negative bacteria. In addition, LptD may be targeted by peptidomimetic antibiotics in Gram-negative bacteria. We also give insights into the directions of future research regarding the mechanisms of polysaccharide export.
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Affiliation(s)
- Biao Yuan
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China.
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, 46 Xinkang Road, Ya’an, Sichuan 625014, China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu city, Sichuan 611130, China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
- Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, 46 Xinkang Road, Ya’an, Sichuan 625014, China
- Key Laboratory of Animal Disease & Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu city, Sichuan 611130, China
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22
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Misra R. Assembly of the β-Barrel Outer Membrane Proteins in Gram-Negative Bacteria, Mitochondria, and Chloroplasts. ISRN MOLECULAR BIOLOGY 2012; 2012:708203. [PMID: 27335668 PMCID: PMC4890855 DOI: 10.5402/2012/708203] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 10/22/2012] [Indexed: 01/12/2023]
Abstract
In the last decade, there has been an explosion of publications on the assembly of β-barrel outer membrane proteins (OMPs), which carry out diverse cellular functions, including solute transport, protein secretion, and assembly of protein and lipid components of the outer membrane. Of the three outer membrane model systems—Gram-negative bacteria, mitochondria and chloroplasts—research on bacterial and mitochondrial systems has so far led the way in dissecting the β-barrel OMP assembly pathways. Many exciting discoveries have been made, including the identification of β-barrel OMP assembly machineries in bacteria and mitochondria, and potentially the core assembly component in chloroplasts. The atomic structures of all five components of the bacterial β-barrel assembly machinery (BAM) complex, except the β-barrel domain of the core BamA protein, have been solved. Structures reveal that these proteins contain domains/motifs known to facilitate protein-protein interactions, which are at the heart of the assembly pathways. While structural information has been valuable, most of our current understanding of the β-barrel OMP assembly pathways has come from genetic, molecular biology, and biochemical analyses. This paper provides a comparative account of the β-barrel OMP assembly pathways in Gram-negative bacteria, mitochondria, and chloroplasts.
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Affiliation(s)
- Rajeev Misra
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
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