1
|
Currie MJ, Davies JS, Scalise M, Gulati A, Wright JD, Newton-Vesty MC, Abeysekera GS, Subramanian R, Wahlgren WY, Friemann R, Allison JR, Mace PD, Griffin MDW, Demeler B, Wakatsuki S, Drew D, Indiveri C, Dobson RCJ, North RA. Structural and biophysical analysis of a Haemophilus influenzae tripartite ATP-independent periplasmic (TRAP) transporter. eLife 2024; 12:RP92307. [PMID: 38349818 PMCID: PMC10942642 DOI: 10.7554/elife.92307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2024] Open
Abstract
Tripartite ATP-independent periplasmic (TRAP) transporters are secondary-active transporters that receive their substrates via a soluble-binding protein to move bioorganic acids across bacterial or archaeal cell membranes. Recent cryo-electron microscopy (cryo-EM) structures of TRAP transporters provide a broad framework to understand how they work, but the mechanistic details of transport are not yet defined. Here we report the cryo-EM structure of the Haemophilus influenzae N-acetylneuraminate TRAP transporter (HiSiaQM) at 2.99 Å resolution (extending to 2.2 Å at the core), revealing new features. The improved resolution (the previous HiSiaQM structure is 4.7 Å resolution) permits accurate assignment of two Na+ sites and the architecture of the substrate-binding site, consistent with mutagenic and functional data. Moreover, rather than a monomer, the HiSiaQM structure is a homodimer. We observe lipids at the dimer interface, as well as a lipid trapped within the fusion that links the SiaQ and SiaM subunits. We show that the affinity (KD) for the complex between the soluble HiSiaP protein and HiSiaQM is in the micromolar range and that a related SiaP can bind HiSiaQM. This work provides key data that enhances our understanding of the 'elevator-with-an-operator' mechanism of TRAP transporters.
Collapse
Affiliation(s)
- Michael J Currie
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology, and School of Biological Sciences, University of CanterburyChristchurchNew Zealand
| | - James S Davies
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology, and School of Biological Sciences, University of CanterburyChristchurchNew Zealand
- Department of Biochemistry and Biophysics, Stockholm UniversityStockholmSweden
| | - Mariafrancesca Scalise
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of CalabriaArcavacata di RendeItaly
| | - Ashutosh Gulati
- Department of Biochemistry and Biophysics, Stockholm UniversityStockholmSweden
| | - Joshua D Wright
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology, and School of Biological Sciences, University of CanterburyChristchurchNew Zealand
| | - Michael C Newton-Vesty
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology, and School of Biological Sciences, University of CanterburyChristchurchNew Zealand
| | - Gayan S Abeysekera
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology, and School of Biological Sciences, University of CanterburyChristchurchNew Zealand
| | - Ramaswamy Subramanian
- Biological Sciences and Biomedical Engineering, Bindley Bioscience Center, Purdue University West LafayetteWest LafayetteUnited States
| | - Weixiao Y Wahlgren
- Department of Chemistry and Molecular Biology, Biochemistry and Structural Biology, University of GothenburgGothenburgSweden
| | - Rosmarie Friemann
- Centre for Antibiotic Resistance Research (CARe) at University of GothenburgGothenburgSweden
| | - Jane R Allison
- Biomolecular Interaction Centre, Digital Life Institute, Maurice Wilkins Centre for Molecular Biodiscovery, and School of Biological Sciences, University of AucklandAucklandNew Zealand
| | - Peter D Mace
- Biochemistry Department, School of Biomedical Sciences, University of OtagoDunedinNew Zealand
| | - Michael DW Griffin
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Bio Molecular Science and Biotechnology Institute, Department of Biochemistry and Pharmacology, University of MelbourneMelbourneAustralia
| | - Borries Demeler
- Department of Chemistry and Biochemistry, University of MontanaMissoulaUnited States
- Department of Chemistry and Biochemistry, University of LethbridgeLethbridgeCanada
| | - Soichi Wakatsuki
- Biological Sciences Division, SLAC National Accelerator LaboratoryMenlo ParkUnited States
- Department of Structural Biology, Stanford University School of MedicineStanfordUnited States
| | - David Drew
- Department of Biochemistry and Biophysics, Stockholm UniversityStockholmSweden
| | - Cesare Indiveri
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of CalabriaArcavacata di RendeItaly
- CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM)BariItaly
| | - Renwick CJ Dobson
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology, and School of Biological Sciences, University of CanterburyChristchurchNew Zealand
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Bio Molecular Science and Biotechnology Institute, Department of Biochemistry and Pharmacology, University of MelbourneMelbourneAustralia
| | - Rachel A North
- Department of Biochemistry and Biophysics, Stockholm UniversityStockholmSweden
- School of Medical Sciences, Faculty of Medicine and Health, University of SydneySydneyAustralia
| |
Collapse
|
2
|
Peter MF, Ruland JA, Kim Y, Hendricks P, Schneberger N, Siebrasse JP, Thomas GH, Kubitscheck U, Hagelueken G. Conformational coupling of the sialic acid TRAP transporter HiSiaQM with its substrate binding protein HiSiaP. Nat Commun 2024; 15:217. [PMID: 38191530 PMCID: PMC10774421 DOI: 10.1038/s41467-023-44327-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 12/08/2023] [Indexed: 01/10/2024] Open
Abstract
The tripartite ATP-independent periplasmic (TRAP) transporters use an extra cytoplasmic substrate binding protein (SBP) to transport a wide variety of substrates in bacteria and archaea. The SBP can adopt an open- or closed state depending on the presence of substrate. The two transmembrane domains of TRAP transporters form a monomeric elevator whose function is strictly dependent on the presence of a sodium ion gradient. Insights from experimental structures, structural predictions and molecular modeling have suggested a conformational coupling between the membrane elevator and the substrate binding protein. Here, we use a disulfide engineering approach to lock the TRAP transporter HiSiaPQM from Haemophilus influenzae in different conformational states. The SBP, HiSiaP, is locked in its substrate-bound form and the transmembrane elevator, HiSiaQM, is locked in either its assumed inward- or outward-facing states. We characterize the disulfide-locked constructs and use single-molecule total internal reflection fluorescence (TIRF) microscopy to study their interactions. Our experiments demonstrate that the SBP and the transmembrane elevator are indeed conformationally coupled, meaning that the open and closed state of the SBP recognize specific conformational states of the transporter and vice versa.
Collapse
Affiliation(s)
- Martin F Peter
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
- Biochemistry Center, Heidelberg University, Im Neuenheimer Feld 328, 69120, Heidelberg, Germany
| | - Jan A Ruland
- Clausius Institute for Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | - Yeojin Kim
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
| | - Philipp Hendricks
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
| | - Niels Schneberger
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
| | - Jan Peter Siebrasse
- Clausius Institute for Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | - Gavin H Thomas
- Department of Biology (Area 10), University of York, York, YO10 5YW, UK
| | - Ulrich Kubitscheck
- Clausius Institute for Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | - Gregor Hagelueken
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany.
| |
Collapse
|
3
|
Soni S, Chahar M, Priyanka, Chugh P, Sharma A, Narasimhan B, Mohan H. Identification of Aztreonam as a potential antibacterial agent against Pasteurella multocida sialic acid binding protein: A combined in silico and in-vitro analysis. Microb Pathog 2023; 185:106398. [PMID: 37852551 DOI: 10.1016/j.micpath.2023.106398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 10/06/2023] [Accepted: 10/14/2023] [Indexed: 10/20/2023]
Abstract
Pasteurella multocida, a Gram-negative zoonotic bacterial pathogen, interacts with the host environment, immune response, and infection through outer membrane proteins, adhesins, and sialic acid binding proteins. Sialic acids provide nutrition and mask bacterial identity, hindering the complement system, facilitates tissue access and biofilm formation. Sialic acid binding protein (SAB) enable adhesion to host cells, immune evasion, and nutrient acquisition, making them potential targets for preventing Pasteurella multocida infections. In this study, in silico molecular docking assessed 11 antibiotics targeting SAB (4MMP) comparing their docking scores to Amoxicillin. As SAB (4MMP) exhibits a highly conserved sequence in various Pasteurella multocida strains, including the specific strain PMR212 studied in this article, with a 96.09% similarity score. Aztreonam and Gentamicin displayed the highest docking scores (-6.025 and -5.718), followed by a 100ns molecular dynamics simulation. Aztreonam exhibited stable simulation with protein RMSD fluctuations of 1.8-2.2 Å. The ligand initially had an RMSD of 1.6 Å, stabilizing at 4.8 Å. Antibiotic sensitivity testing confirmed Aztreonam's efficacy with the largest inhibition zone of 42 mm, while Amoxicillin and Gentamicin had inhibition zones of 32 mm and 25 mm, respectively. According to CLSI guidelines, all three antibiotics were effective against Pasteurella multocida. Aztreonam's superior efficacy positions it as a promising candidate for further investigation in targeting Pasteurella multocida.
Collapse
Affiliation(s)
- Subodh Soni
- Centre for Medical Biotechnology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
| | - Manjeet Chahar
- Centre for Medical Biotechnology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
| | - Priyanka
- Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
| | - Pooja Chugh
- Centre for Medical Biotechnology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
| | - Aastha Sharma
- Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
| | | | - Hari Mohan
- Centre for Medical Biotechnology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India.
| |
Collapse
|
4
|
Kim J, Kim BS. Bacterial Sialic Acid Catabolism at the Host–Microbe Interface. J Microbiol 2023; 61:369-377. [PMID: 36972004 DOI: 10.1007/s12275-023-00035-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 02/27/2023] [Accepted: 03/06/2023] [Indexed: 03/29/2023]
Abstract
Sialic acids consist of nine-carbon keto sugars that are commonly found at the terminal end of mucins. This positional feature of sialic acids contributes to host cell interactions but is also exploited by some pathogenic bacteria in evasion of host immune system. Moreover, many commensals and pathogens use sialic acids as an alternative energy source to survive within the mucus-covered host environments, such as the intestine, vagina, and oral cavity. Among the various biological events mediated by sialic acids, this review will focus on the processes necessary for the catabolic utilization of sialic acid in bacteria. First of all, transportation of sialic acid should be preceded before its catabolism. There are four types of transporters that are used for sialic acid uptake; the major facilitator superfamily (MFS), the tripartite ATP-independent periplasmic C4-dicarboxilate (TRAP) multicomponent transport system, the ATP binding cassette (ABC) transporter, and the sodium solute symporter (SSS). After being moved by these transporters, sialic acid is degraded into an intermediate of glycolysis through the well-conserved catabolic pathway. The genes encoding the catabolic enzymes and transporters are clustered into an operon(s), and their expression is tightly controlled by specific transcriptional regulators. In addition to these mechanisms, we will cover some researches about sialic acid utilization by oral pathogens.
Collapse
Affiliation(s)
- Jaeeun Kim
- Department of Food Science and Biotechnology, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Byoung Sik Kim
- Department of Food Science and Biotechnology, Ewha Womans University, Seoul, 03760, Republic of Korea.
| |
Collapse
|
5
|
Davies JS, Currie MJ, North RA, Scalise M, Wright JD, Copping JM, Remus DM, Gulati A, Morado DR, Jamieson SA, Newton-Vesty MC, Abeysekera GS, Ramaswamy S, Friemann R, Wakatsuki S, Allison JR, Indiveri C, Drew D, Mace PD, Dobson RCJ. Structure and mechanism of a tripartite ATP-independent periplasmic TRAP transporter. Nat Commun 2023; 14:1120. [PMID: 36849793 PMCID: PMC9971032 DOI: 10.1038/s41467-023-36590-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 02/07/2023] [Indexed: 03/01/2023] Open
Abstract
In bacteria and archaea, tripartite ATP-independent periplasmic (TRAP) transporters uptake essential nutrients. TRAP transporters receive their substrates via a secreted soluble substrate-binding protein. How a sodium ion-driven secondary active transporter is strictly coupled to a substrate-binding protein is poorly understood. Here we report the cryo-EM structure of the sialic acid TRAP transporter SiaQM from Photobacterium profundum at 2.97 Å resolution. SiaM comprises a "transport" domain and a "scaffold" domain, with the transport domain consisting of helical hairpins as seen in the sodium ion-coupled elevator transporter VcINDY. The SiaQ protein forms intimate contacts with SiaM to extend the size of the scaffold domain, suggesting that TRAP transporters may operate as monomers, rather than the typically observed oligomers for elevator-type transporters. We identify the Na+ and sialic acid binding sites in SiaM and demonstrate a strict dependence on the substrate-binding protein SiaP for uptake. We report the SiaP crystal structure that, together with docking studies, suggest the molecular basis for how sialic acid is delivered to the SiaQM transporter complex. We thus propose a model for substrate transport by TRAP proteins, which we describe herein as an 'elevator-with-an-operator' mechanism.
Collapse
Affiliation(s)
- James S Davies
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology and School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand.,Department of Biochemistry and Biophysics, Stockholm University, 10691, Stockholm, Sweden
| | - Michael J Currie
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology and School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand
| | - Rachel A North
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology and School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand. .,Department of Biochemistry and Biophysics, Stockholm University, 10691, Stockholm, Sweden.
| | - Mariafrancesca Scalise
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036, Arcavacata di Rende, Italy
| | - Joshua D Wright
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology and School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand
| | - Jack M Copping
- Biomolecular Interaction Centre, Digital Life Institute, Maurice Wilkins Centre for Molecular Biodiscovery, and School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand
| | - Daniela M Remus
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology and School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand
| | - Ashutosh Gulati
- Department of Biochemistry and Biophysics, Stockholm University, 10691, Stockholm, Sweden
| | - Dustin R Morado
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden
| | - Sam A Jamieson
- Biochemistry Department, School of Biomedical Sciences, University of Otago, Dunedin, 9054, New Zealand
| | - Michael C Newton-Vesty
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology and School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand
| | - Gayan S Abeysekera
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology and School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand
| | - Subramanian Ramaswamy
- Biological Sciences and Biomedical Engineering, Bindley Bioscience Center, Purdue University, 1203 W State St, West Lafayette, IN 47906, USA
| | - Rosmarie Friemann
- Centre for Antibiotic Resistance Research (CARe) at University of Gothenburg, Box 440, S-40530, Gothenburg, Sweden
| | - Soichi Wakatsuki
- Biological Sciences Division, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA.,Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Jane R Allison
- Biomolecular Interaction Centre, Digital Life Institute, Maurice Wilkins Centre for Molecular Biodiscovery, and School of Biological Sciences, University of Auckland, Auckland, 1010, New Zealand
| | - Cesare Indiveri
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036, Arcavacata di Rende, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Via Amendola 122/O, 70126, Bari, Italy
| | - David Drew
- Department of Biochemistry and Biophysics, Stockholm University, 10691, Stockholm, Sweden
| | - Peter D Mace
- Biochemistry Department, School of Biomedical Sciences, University of Otago, Dunedin, 9054, New Zealand
| | - Renwick C J Dobson
- Biomolecular Interaction Centre, Maurice Wilkins Centre for Biodiscovery, MacDiarmid Institute for Advanced Materials and Nanotechnology and School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand. .,Bio21 Molecular Science and Biotechnology Institute, Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, 3010, Australia.
| |
Collapse
|
6
|
Bell A, Severi E, Owen CD, Latousakis D, Juge N. Biochemical and structural basis of sialic acid utilization by gut microbes. J Biol Chem 2023; 299:102989. [PMID: 36758803 PMCID: PMC10017367 DOI: 10.1016/j.jbc.2023.102989] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 02/01/2023] [Accepted: 02/02/2023] [Indexed: 02/10/2023] Open
Abstract
The human gastrointestinal (GI) tract harbors diverse microbial communities collectively known as the gut microbiota that exert a profound impact on human health and disease. The repartition and availability of sialic acid derivatives in the gut have a significant impact on the modulation of gut microbes and host susceptibility to infection and inflammation. Although N-acetylneuraminic acid (Neu5Ac) is the main form of sialic acids in humans, the sialic acid family regroups more than 50 structurally and chemically distinct modified derivatives. In the GI tract, sialic acids are found in the terminal location of mucin glycan chains constituting the mucus layer and also come from human milk oligosaccharides in the infant gut or from meat-based foods in adults. The repartition of sialic acid in the GI tract influences the gut microbiota composition and pathogen colonization. In this review, we provide an update on the mechanisms underpinning sialic acid utilization by gut microbes, focusing on sialidases, transporters, and metabolic enzymes.
Collapse
Affiliation(s)
- Andrew Bell
- Quadram Institute Bioscience, Gut Microbes and Health Institute Strategic Programme, Norwich, United Kingdom
| | - Emmanuele Severi
- Microbes in Health and Disease, Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - C David Owen
- Diamond Light Source Ltd, Diamond House, Harwell Science and Innovation Campus, Didcot, United Kingdom
| | - Dimitrios Latousakis
- Quadram Institute Bioscience, Gut Microbes and Health Institute Strategic Programme, Norwich, United Kingdom
| | - Nathalie Juge
- Quadram Institute Bioscience, Gut Microbes and Health Institute Strategic Programme, Norwich, United Kingdom.
| |
Collapse
|
7
|
Bozzola T, Johnsson RE, Nilsson UJ, Ellervik U. Sialic Acid 4-N-Piperazine and Piperidine Derivatives Bind with High Affinity to the P. mirabilis Sialic Acid Sodium Solute Symporter. ChemMedChem 2022; 17:e202200351. [PMID: 36121381 PMCID: PMC10092485 DOI: 10.1002/cmdc.202200351] [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: 06/30/2022] [Revised: 09/16/2022] [Indexed: 01/14/2023]
Abstract
In search for novel antibacterial compounds, bacterial sialic acid uptake inhibition represents a promising strategy. Sialic acid plays a critical role for growth and colonisation of several pathogenic bacteria, and its uptake inhibition in bacteria was recently demonstrated to be a viable strategy by targeting the SiaT sodium solute symporters from Proteus mirabilis and Staphylococcus aureus. Here we report the design, synthesis and evaluation of potential sialic acid uptake inhibitors bearing 4-N-piperidine and piperazine moieties. The 4-N-derivatives were obtained via 4-N-functionalization with piperidine and piperazine nucleophiles in an efficient direct substitution of the 4-O-acetate of Neu5Ac. Evaluation for binding to bacterial transport proteins with nanoDSF and ITC revealed compounds possessing nanomolar affinity for the P. mirabilis SiaT symporter. Computational analyses indicate the engagement of a previously untargeted portion of the binding site.
Collapse
Affiliation(s)
- Tiago Bozzola
- Department of Chemistry, Lund University, P.O. Box 124, 221 00, Lund, Sweden
| | | | - Ulf J Nilsson
- Department of Chemistry, Lund University, P.O. Box 124, 221 00, Lund, Sweden
| | - Ulf Ellervik
- Department of Chemistry, Lund University, P.O. Box 124, 221 00, Lund, Sweden
| |
Collapse
|
8
|
Dudek B, Rybka J, Bugla-Płoskońska G, Korzeniowska-Kowal A, Futoma-Kołoch B, Pawlak A, Gamian A. Biological functions of sialic acid as a component of bacterial endotoxin. Front Microbiol 2022; 13:1028796. [PMID: 36338080 PMCID: PMC9631793 DOI: 10.3389/fmicb.2022.1028796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 10/05/2022] [Indexed: 11/28/2022] Open
Abstract
Lipopolysaccharide (endotoxin, LPS) is an important Gram-negative bacteria antigen. LPS of some bacteria contains sialic acid (Neu5Ac) as a component of O-antigen (O-Ag), in this review we present an overview of bacteria in which the presence of Neu5Ac has been confirmed in their outer envelope and the possible ways that bacteria can acquire Neu5Ac. We explain the role of Neu5Ac in bacterial pathogenesis, and also involvement of Neu5Ac in bacterial evading the host innate immunity response and molecular mimicry phenomenon. We also highlight the role of sialic acid in the mechanism of bacterial resistance to action of serum complement. Despite a number of studies on involvement of Neu5Ac in bacterial pathogenesis many aspects of this phenomenon are still not understood.
Collapse
Affiliation(s)
- Bartłomiej Dudek
- Department of Microbiology, University of Wrocław, Wrocław, Poland
- *Correspondence: Bartłomiej Dudek,
| | - Jacek Rybka
- Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | | | - Agnieszka Korzeniowska-Kowal
- Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | | | | | - Andrzej Gamian
- Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
- Andrzej Gamian,
| |
Collapse
|
9
|
Peter MF, Ruland JA, Depping P, Schneberger N, Severi E, Moecking J, Gatterdam K, Tindall S, Durand A, Heinz V, Siebrasse JP, Koenig PA, Geyer M, Ziegler C, Kubitscheck U, Thomas GH, Hagelueken G. Structural and mechanistic analysis of a tripartite ATP-independent periplasmic TRAP transporter. Nat Commun 2022; 13:4471. [PMID: 35927235 PMCID: PMC9352664 DOI: 10.1038/s41467-022-31907-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 07/08/2022] [Indexed: 11/27/2022] Open
Abstract
Tripartite ATP-independent periplasmic (TRAP) transporters are found widely in bacteria and archaea and consist of three structural domains, a soluble substrate-binding protein (P-domain), and two transmembrane domains (Q- and M-domains). HiSiaPQM and its homologs are TRAP transporters for sialic acid and are essential for host colonization by pathogenic bacteria. Here, we reconstitute HiSiaQM into lipid nanodiscs and use cryo-EM to reveal the structure of a TRAP transporter. It is composed of 16 transmembrane helices that are unexpectedly structurally related to multimeric elevator-type transporters. The idiosyncratic Q-domain of TRAP transporters enables the formation of a monomeric elevator architecture. A model of the tripartite PQM complex is experimentally validated and reveals the coupling of the substrate-binding protein to the transporter domains. We use single-molecule total internal reflection fluorescence (TIRF) microscopy in solid-supported lipid bilayers and surface plasmon resonance to study the formation of the tripartite complex and to investigate the impact of interface mutants. Furthermore, we characterize high-affinity single variable domains on heavy chain (VHH) antibodies that bind to the periplasmic side of HiSiaQM and inhibit sialic acid uptake, providing insight into how TRAP transporter function might be inhibited in vivo.
Collapse
Affiliation(s)
- Martin F Peter
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
| | - Jan A Ruland
- Institute for Physical und Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53127, Bonn, Germany
| | - Peer Depping
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
- Aston Centre for Membrane Proteins and Lipids Research, Aston St., B4 7ET, Birmingham, UK
| | - Niels Schneberger
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
| | - Emmanuele Severi
- Department of Biology (Area 10), University of York, York, YO10 5YW, UK
- Biosciences Institute, Newcastle University, Newcastle, NE2 4HH, UK
| | - Jonas Moecking
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
| | - Karl Gatterdam
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
| | - Sarah Tindall
- Department of Biology (Area 10), University of York, York, YO10 5YW, UK
| | - Alexandre Durand
- Institut de Génétique et de Biologie Molecule et Cellulaire, 1 Rue Laurent Fries, 67404, Illkirch Cedex, France
| | - Veronika Heinz
- Institute of Biophysics and Biophysical Chemistry, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Jan Peter Siebrasse
- Institute for Physical und Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53127, Bonn, Germany
| | - Paul-Albert Koenig
- Core Facility Nanobodies, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
| | - Matthias Geyer
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany
| | - Christine Ziegler
- Institute of Biophysics and Biophysical Chemistry, University of Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Ulrich Kubitscheck
- Institute for Physical und Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53127, Bonn, Germany
| | - Gavin H Thomas
- Department of Biology (Area 10), University of York, York, YO10 5YW, UK
| | - Gregor Hagelueken
- Institute of Structural Biology, University of Bonn, Venusberg-Campus 1, 53127, Bonn, Germany.
| |
Collapse
|
10
|
Jennings MP, Day CJ, Atack JM. How bacteria utilize sialic acid during interactions with the host: snip, snatch, dispatch, match and attach. MICROBIOLOGY (READING, ENGLAND) 2022; 168:001157. [PMID: 35316172 PMCID: PMC9558349 DOI: 10.1099/mic.0.001157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 02/08/2022] [Indexed: 12/16/2022]
Abstract
N -glycolylneuraminic acid (Neu5Gc), and its precursor N-acetylneuraminic acid (Neu5Ac), commonly referred to as sialic acids, are two of the most common glycans found in mammals. Humans carry a mutation in the enzyme that converts Neu5Ac into Neu5Gc, and as such, expression of Neu5Ac can be thought of as a 'human specific' trait. Bacteria can utilize sialic acids as a carbon and energy source and have evolved multiple ways to take up sialic acids. In order to generate free sialic acid, many bacteria produce sialidases that cleave sialic acid residues from complex glycan structures. In addition, sialidases allow escape from innate immune mechanisms, and can synergize with other virulence factors such as toxins. Human-adapted pathogens have evolved a preference for Neu5Ac, with many bacterial adhesins, and major classes of toxin, specifically recognizing Neu5Ac containing glycans as receptors. The preference of human-adapted pathogens for Neu5Ac also occurs during biosynthesis of surface structures such as lipo-oligosaccharide (LOS), lipo-polysaccharide (LPS) and polysaccharide capsules, subverting the human host immune system by mimicking the host. This review aims to provide an update on the advances made in understanding the role of sialic acid in bacteria-host interactions made in the last 5-10 years, and put these findings into context by highlighting key historical discoveries. We provide a particular focus on 'molecular mimicry' and incorporation of sialic acid onto the bacterial outer-surface, and the role of sialic acid as a receptor for bacterial adhesins and toxins.
Collapse
Affiliation(s)
- Michael P. Jennings
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Christopher J. Day
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - John M. Atack
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
- School of Environment and Science, Griffith University, Gold Coast, Queensland, Australia
| |
Collapse
|
11
|
Davies JS, Currie MJ, Wright JD, Newton-Vesty MC, North RA, Mace PD, Allison JR, Dobson RCJ. Selective Nutrient Transport in Bacteria: Multicomponent Transporter Systems Reign Supreme. Front Mol Biosci 2021; 8:699222. [PMID: 34268334 PMCID: PMC8276074 DOI: 10.3389/fmolb.2021.699222] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 06/02/2021] [Indexed: 11/24/2022] Open
Abstract
Multicomponent transporters are used by bacteria to transport a wide range of nutrients. These systems use a substrate-binding protein to bind the nutrient with high affinity and then deliver it to a membrane-bound transporter for uptake. Nutrient uptake pathways are linked to the colonisation potential and pathogenicity of bacteria in humans and may be candidates for antimicrobial targeting. Here we review current research into bacterial multicomponent transport systems, with an emphasis on the interaction at the membrane, as well as new perspectives on the role of lipids and higher oligomers in these complex systems.
Collapse
Affiliation(s)
- James S Davies
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Michael J Currie
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Joshua D Wright
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Michael C Newton-Vesty
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Rachel A North
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Peter D Mace
- Biochemistry Department, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Jane R Allison
- Maurice Wilkins Centre for Molecular Biodiscovery and School of Biological Sciences, Digital Life Institute, University of Auckland, Auckland, New Zealand
| | - Renwick C J Dobson
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand.,Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, Australia
| |
Collapse
|
12
|
Severi E, Rudden M, Bell A, Palmer T, Juge N, Thomas GH. Multiple evolutionary origins reflect the importance of sialic acid transporters in the colonization potential of bacterial pathogens and commensals. Microb Genom 2021; 7. [PMID: 34184979 PMCID: PMC8461474 DOI: 10.1099/mgen.0.000614] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Located at the tip of cell surface glycoconjugates, sialic acids are at the forefront of host-microbe interactions and, being easily liberated by sialidase enzymes, are used as metabolites by numerous bacteria, particularly by pathogens and commensals living on or near diverse mucosal surfaces. These bacteria rely on specific transporters for the acquisition of host-derived sialic acids. Here, we present the first comprehensive genomic and phylogenetic analysis of bacterial sialic acid transporters, leading to the identification of multiple new families and subfamilies. Our phylogenetic analysis suggests that sialic acid-specific transport has evolved independently at least eight times during the evolution of bacteria, from within four of the major families/superfamilies of bacterial transporters, and we propose a robust classification scheme to bring together a myriad of different nomenclatures that exist to date. The new transporters discovered occur in diverse bacteria, including Spirochaetes, Bacteroidetes, Planctomycetes and Verrucomicrobia, many of which are species that have not been previously recognized to have sialometabolic capacities. Two subfamilies of transporters stand out in being fused to the sialic acid mutarotase enzyme, NanM, and these transporter fusions are enriched in bacteria present in gut microbial communities. Our analysis supports the increasing experimental evidence that competition for host-derived sialic acid is a key phenotype for successful colonization of complex mucosal microbiomes, such that a strong evolutionary selection has occurred for the emergence of sialic acid specificity within existing transporter architectures.
Collapse
Affiliation(s)
- Emmanuele Severi
- Department of Biology, University of York, York, UK.,Microbes in Health and Disease, Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | | | - Andrew Bell
- Gut Microbes and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | - Tracy Palmer
- Microbes in Health and Disease, Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Nathalie Juge
- Gut Microbes and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | | |
Collapse
|
13
|
Peter MF, Gebhardt C, Glaenzer J, Schneberger N, de Boer M, Thomas GH, Cordes T, Hagelueken G. Triggering Closure of a Sialic Acid TRAP Transporter Substrate Binding Protein through Binding of Natural or Artificial Substrates. J Mol Biol 2021; 433:166756. [PMID: 33316271 DOI: 10.1016/j.jmb.2020.166756] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/07/2020] [Accepted: 12/07/2020] [Indexed: 12/20/2022]
Abstract
The pathogens Vibrio cholerae and Haemophilus influenzae use tripartite ATP-independent periplasmic transporters (TRAPs) to scavenge sialic acid from host tissues. They use it as a nutrient or to evade the innate immune system by sialylating surface lipopolysaccharides. An essential component of TRAP transporters is a periplasmic substrate binding protein (SBP). Without substrate, the SBP has been proposed to rest in an open-state, which is not recognised by the transporter. Substrate binding induces a conformational change of the SBP and it is thought that this closed state is recognised by the transporter, triggering substrate translocation. Here we use real time single molecule FRET experiments and crystallography to investigate the open- to closed-state transition of VcSiaP, the SBP of the sialic acid TRAP transporter from V. cholerae. We show that the conformational switching of VcSiaP is strictly substrate induced, confirming an important aspect of the proposed transport mechanism. Two new crystal structures of VcSiaP provide insights into the closing mechanism. While the first structure contains the natural ligand, sialic acid, the second structure contains an artificial peptide in the sialic acid binding site. Together, the two structures suggest that the ligand itself stabilises the closed state and that SBP closure is triggered by physically bridging the gap between the two lobes of the SBP. Finally, we demonstrate that the affinity for the artificial peptide substrate can be substantially increased by varying its amino acid sequence and by this, serve as a starting point for the development of peptide-based inhibitors of TRAP transporters.
Collapse
Affiliation(s)
- Martin F Peter
- Institute of Structural Biology, University of Bonn, 53127 Bonn, Germany
| | - Christian Gebhardt
- Physical and Synthetic Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Janin Glaenzer
- Institute of Structural Biology, University of Bonn, 53127 Bonn, Germany
| | - Niels Schneberger
- Institute of Structural Biology, University of Bonn, 53127 Bonn, Germany
| | - Marijn de Boer
- Molecular Microscopy Research Group, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Gavin H Thomas
- Department of Biology (Area 10), University of York, York YO10 5YW, UK
| | - Thorben Cordes
- Physical and Synthetic Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany; Molecular Microscopy Research Group, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Gregor Hagelueken
- Institute of Structural Biology, University of Bonn, 53127 Bonn, Germany.
| |
Collapse
|
14
|
Manjunath L, Coombes D, Davies J, Dhurandhar M, Tiwari VR, Dobson RCJ, Sowdhamini R, Ramaswamy S, Bose S. Quaternary variations in the structural assembly of N-acetylglucosamine-6-phosphate deacetylase from Pasteurella multocida. Proteins 2020; 89:81-93. [PMID: 32865821 DOI: 10.1002/prot.25996] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 07/14/2020] [Accepted: 08/25/2020] [Indexed: 12/13/2022]
Abstract
N-acetylglucosamine 6-phosphate deacetylase (NagA) catalyzes the conversion of N-acetylglucosamine-6-phosphate to glucosamine-6-phosphate in amino sugar catabolism. This conversion is an essential step in the catabolism of sialic acid in several pathogenic bacteria, including Pasteurella multocida, and thus NagA is identified as a potential drug target. Here, we report the unique structural features of NagA from P. multocida (PmNagA) resolved to 1.95 Å. PmNagA displays an altered quaternary architecture with unique interface interactions compared to its close homolog, the Escherichia coli NagA (EcNagA). We confirmed that the altered quaternary structure is not a crystallographic artifact using single particle electron cryo-microscopy. Analysis of the determined crystal structure reveals a set of hot-spot residues involved in novel interactions at the dimer-dimer interface. PmNagA binds to one Zn2+ ion in the active site and demonstrates kinetic parameters comparable to other bacterial homologs. Kinetic studies reveal that at high substrate concentrations (~10-fold the KM ), the tetrameric PmNagA displays hysteresis similar to its distant neighbor, the dimeric Staphylococcus aureus NagA (SaNagA). Our findings provide key information on structural and functional properties of NagA in P. multocida that could be utilized to design novel antibacterials.
Collapse
Affiliation(s)
- Lavanyaa Manjunath
- Institute for Stem Cell Science and Regenerative Medicine, NCBS, GKVK Campus, Bangalore, Karnataka, India
- Manipal Academy of Higher Education, Tiger Circle, Manipal, Karnataka, India
| | - David Coombes
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - James Davies
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Mugdha Dhurandhar
- National Centre for Biological Sciences, GKVK Campus, Bangalore, Karnataka, India
| | - Vikas R Tiwari
- National Centre for Biological Sciences, GKVK Campus, Bangalore, Karnataka, India
| | - Renwick C J Dobson
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- Bio21 Molecular Science and Biotechnology Institute, Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia
| | - R Sowdhamini
- National Centre for Biological Sciences, GKVK Campus, Bangalore, Karnataka, India
| | - S Ramaswamy
- Institute for Stem Cell Science and Regenerative Medicine, NCBS, GKVK Campus, Bangalore, Karnataka, India
- Department of Biological Sciences and Department of Biomedical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Sucharita Bose
- Institute for Stem Cell Science and Regenerative Medicine, NCBS, GKVK Campus, Bangalore, Karnataka, India
| |
Collapse
|
15
|
Glycan cross-feeding supports mutualism between Fusobacterium and the vaginal microbiota. PLoS Biol 2020; 18:e3000788. [PMID: 32841232 PMCID: PMC7447053 DOI: 10.1371/journal.pbio.3000788] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 07/10/2020] [Indexed: 12/14/2022] Open
Abstract
Women with bacterial vaginosis (BV), an imbalance of the vaginal microbiome, are more likely to be colonized by potential pathogens such as Fusobacterium nucleatum, a bacterium linked with intrauterine infection and preterm birth. However, the conditions and mechanisms supporting pathogen colonization during vaginal dysbiosis remain obscure. We demonstrate that sialidase activity, a diagnostic feature of BV, promoted F. nucleatum foraging and growth on mammalian sialoglycans, a nutrient resource that was otherwise inaccessible because of the lack of endogenous F. nucleatum sialidase. In mice with sialidase-producing vaginal microbiotas, mutant F. nucleatum unable to consume sialic acids was impaired in vaginal colonization. These experiments in mice also led to the discovery that F. nucleatum may also “give back” to the community by reinforcing sialidase activity, a biochemical feature of human dysbiosis. Using human vaginal bacterial communities, we show that F. nucleatum supported robust outgrowth of Gardnerella vaginalis, a major sialidase producer and one of the most abundant organisms in BV. These results illustrate that mutually beneficial relationships between vaginal bacteria support pathogen colonization and may help maintain features of dysbiosis. These findings challenge the simplistic dogma that the mere absence of “healthy” lactobacilli is the sole mechanism that creates a permissive environment for pathogens during vaginal dysbiosis. Given the ubiquity of F. nucleatum in the human mouth, these studies also suggest a possible mechanism underlying links between vaginal dysbiosis and oral sex. Bacterial mutualism involving the prominent oral bacterium Fusobacterium nucleatum may drive vaginal dysbiosis in women and could help to explain the clinical correlations between vaginal dysbiosis and oral sex.
Collapse
|
16
|
Bell A, Severi E, Lee M, Monaco S, Latousakis D, Angulo J, Thomas GH, Naismith JH, Juge N. Uncovering a novel molecular mechanism for scavenging sialic acids in bacteria. J Biol Chem 2020; 295:13724-13736. [PMID: 32669363 PMCID: PMC7535918 DOI: 10.1074/jbc.ra120.014454] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/10/2020] [Indexed: 12/12/2022] Open
Abstract
The human gut symbiont Ruminococcus gnavus scavenges host-derived N-acetylneuraminic acid (Neu5Ac) from mucins by converting it to 2,7-anhydro-Neu5Ac. We previously showed that 2,7-anhydro-Neu5Ac is transported into R. gnavus ATCC 29149 before being converted back to Neu5Ac for further metabolic processing. However, the molecular mechanism leading to the conversion of 2,7-anhydro-Neu5Ac to Neu5Ac remained elusive. Using 1D and 2D NMR, we elucidated the multistep enzymatic mechanism of the oxidoreductase (RgNanOx) that leads to the reversible conversion of 2,7-anhydro-Neu5Ac to Neu5Ac through formation of a 4-keto-2-deoxy-2,3-dehydro-N-acetylneuraminic acid intermediate and NAD+ regeneration. The crystal structure of RgNanOx in complex with the NAD+ cofactor showed a protein dimer with a Rossman fold. Guided by the RgNanOx structure, we identified catalytic residues by site-directed mutagenesis. Bioinformatics analyses revealed the presence of RgNanOx homologues across Gram-negative and Gram-positive bacterial species and co-occurrence with sialic acid transporters. We showed by electrospray ionization spray MS that the Escherichia coli homologue YjhC displayed activity against 2,7-anhydro-Neu5Ac and that E. coli could catabolize 2,7-anhydro-Neu5Ac. Differential scanning fluorimetry analyses confirmed the binding of YjhC to the substrates 2,7-anhydro-Neu5Ac and Neu5Ac, as well as to co-factors NAD and NADH. Finally, using E. coli mutants and complementation growth assays, we demonstrated that 2,7-anhydro-Neu5Ac catabolism in E. coli depended on YjhC and on the predicted sialic acid transporter YjhB. These results revealed the molecular mechanisms of 2,7-anhydro-Neu5Ac catabolism across bacterial species and a novel sialic acid transport and catabolism pathway in E. coli.
Collapse
Affiliation(s)
- Andrew Bell
- Gut Microbes and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | | | - Micah Lee
- Division of Structural Biology, University of Oxford, Headington, Oxford, United Kingdom
| | - Serena Monaco
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Dimitrios Latousakis
- Gut Microbes and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Jesus Angulo
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich, United Kingdom; Departamento de Química Orgánica, Universidad de Sevilla, Sevilla, Spain; Instituto de Investigaciones Químicas (CSIC-US), Sevilla, Spain
| | - Gavin H Thomas
- Department of Biology, University of York, York, United Kingdom
| | - James H Naismith
- Division of Structural Biology, University of Oxford, Headington, Oxford, United Kingdom
| | - Nathalie Juge
- Gut Microbes and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich, United Kingdom.
| |
Collapse
|
17
|
Zernia S, van der Heide NJ, Galenkamp NS, Gouridis G, Maglia G. Current Blockades of Proteins inside Nanopores for Real-Time Metabolome Analysis. ACS NANO 2020; 14:2296-2307. [PMID: 32003969 PMCID: PMC7045694 DOI: 10.1021/acsnano.9b09434] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 01/31/2020] [Indexed: 05/14/2023]
Abstract
Biological nanopores are emerging as powerful and low-cost sensors for real-time analysis of biological samples. Proteins can be incorporated inside the nanopore, and ligand binding to the protein adaptor yields changes in nanopore conductance. In order to understand the origin of these conductance changes and develop sensors for detecting metabolites, we tested the signal originating from 13 different protein adaptors. We found that the quality of the protein signal depended on both the size and charge of the protein. The engineering of a dipole within the surface of the adaptor reduced the current noise by slowing the protein dynamics within the nanopore. Further, the charge of the ligand and the induced conformational changes of the adaptor defined the conductance changes upon metabolite binding, suggesting that the protein resides in an electrokinetic minimum within the nanopore, the position of which is altered by the ligand. These results represent an important step toward understanding the dynamics of the electrophoretic trapping of proteins inside nanopores and will allow developing next-generation sensors for metabolome analysis.
Collapse
Affiliation(s)
- Sarah Zernia
- Groningen
Biomolecular Sciences & Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Nieck Jordy van der Heide
- Groningen
Biomolecular Sciences & Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Nicole Stéphanie Galenkamp
- Groningen
Biomolecular Sciences & Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Giorgos Gouridis
- Rega
Institute for Medical Research, Laboratory of Molecular Bacteriology, KU Leuven, Herestraat 49, Box 1037, 3000 Leuven, Belgium
| | - Giovanni Maglia
- Groningen
Biomolecular Sciences & Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| |
Collapse
|
18
|
Elucidation of a sialic acid metabolism pathway in mucus-foraging Ruminococcus gnavus unravels mechanisms of bacterial adaptation to the gut. Nat Microbiol 2019; 4:2393-2404. [PMID: 31636419 PMCID: PMC6881182 DOI: 10.1038/s41564-019-0590-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Accepted: 09/12/2019] [Indexed: 12/26/2022]
Abstract
Sialic acid (Neu5Ac) is commonly found in terminal location of colonic mucins glycans where it is a much-coveted nutrient for gut bacteria including Ruminococcus gnavus. R. gnavus is part of the healthy gut microbiota in humans but shows a disproportionate representation in diseases. There is therefore a need in understanding the molecular mechanisms underpinning its adaptation to the gut. Previous in vitro work demonstrated that R. gnavus mucin glycan-foraging strategy is strain-dependent and associated with the expression of an intramolecular trans-sialidase releasing 2,7-anhydro-Neu5Ac instead of Neu5Ac from mucins. Here, we have unravelled the metabolism pathway of 2,7-anhydro-Neu5Ac in R. gnavus which is underpinned by the exquisite specificity of the sialic transporter for 2,7-anhydro-Neu5Ac, and by the action of an oxidoreductase converting 2,7-anhydro-Neu5Ac into Neu5Ac which then becomes substrate of a Neu5Ac-specific aldolase. Having generated a R. gnavus nan cluster deletion mutant that lost the ability to grow on sialylated substrates, we showed that in gnotobiotic mice colonised with R. gnavus wild-type and mutant strains, the fitness of the nan mutant was significantly impaired with a reduced ability to colonise the mucus layer. Overall, our study revealed a unique sialic acid pathway in bacteria, with significant implications for the spatial adaptation of mucin-foraging gut symbionts in health and disease.
Collapse
|
19
|
Bose S, Purkait D, Joseph D, Nayak V, Subramanian R. Structural and functional characterization of CMP-N-acetylneuraminate synthetase from Vibrio cholerae. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2019; 75:564-577. [PMID: 31205019 PMCID: PMC6580227 DOI: 10.1107/s2059798319006831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Accepted: 05/13/2019] [Indexed: 11/10/2022]
Abstract
CMP-N-acetylneuraminate synthetase (CMAS) is a key enzyme in the sialic acid incorporation pathway and plays a crucial role in the virulence and survival of several pathogenic bacteria. Here, the structural and functional properties of CMAS from the pathogenic bacterium Vibrio cholerae are reported. Upon CDP binding, a partial domain closure is observed that was previously unreported in homologous structures. Kinetic studies reveal that the enzyme shows substrate promiscuity and can activate both Neu5Ac and Neu5Gc. Several pathogenic bacteria utilize sialic acid, including host-derived N-acetylneuraminic acid (Neu5Ac), in at least two ways: they use it as a nutrient source and as a host-evasion strategy by coating themselves with Neu5Ac. Given the significant role of sialic acid in pathogenesis and host-gut colonization by various pathogenic bacteria, including Neisseria meningitidis, Haemophilus influenzae, Pasteurella multocida and Vibrio cholerae, several enzymes of the sialic acid catabolic, biosynthetic and incorporation pathways are considered to be potential drug targets. In this work, findings on the structural and functional characterization of CMP-N-acetylneuraminate synthetase (CMAS), a key enzyme in the incorporation pathway, from Vibrio cholerae are reported. CMAS catalyzes the synthesis of CMP-sialic acid by utilizing CTP and sialic acid. Crystal structures of the apo and the CDP-bound forms of the enzyme were determined, which allowed the identification of the metal cofactor Mg2+ in the active site interacting with CDP and the invariant Asp215 residue. While open and closed structural forms of the enzyme from eukaryotic and other bacterial species have already been characterized, a partially closed structure of V. cholerae CMAS (VcCMAS) observed upon CDP binding, representing an intermediate state, is reported here. The kinetic data suggest that VcCMAS is capable of activating the two most common sialic acid derivatives, Neu5Ac and Neu5Gc. Amino-acid sequence and structural comparison of the active site of VcCMAS with those of eukaryotic and other bacterial counterparts reveal a diverse hydrophobic pocket that interacts with the C5 substituents of sialic acid. Analyses of the thermodynamic signatures obtained from the binding of the nucleotide (CTP) and the product (CMP-sialic acid) to VcCMAS provide fundamental information on the energetics of the binding process.
Collapse
Affiliation(s)
- Sucharita Bose
- Institute for Stem Cell Science and Regenerative Medicine, GKVK Post, Bellary Road, Bangalore 560 065, India
| | - Debayan Purkait
- Institute for Stem Cell Science and Regenerative Medicine, GKVK Post, Bellary Road, Bangalore 560 065, India
| | - Deepthi Joseph
- Institute for Stem Cell Science and Regenerative Medicine, GKVK Post, Bellary Road, Bangalore 560 065, India
| | - Vinod Nayak
- Institute for Stem Cell Science and Regenerative Medicine, GKVK Post, Bellary Road, Bangalore 560 065, India
| | - Ramaswamy Subramanian
- Institute for Stem Cell Science and Regenerative Medicine, GKVK Post, Bellary Road, Bangalore 560 065, India
| |
Collapse
|
20
|
Marinelli F, Fiorin G. Structural Characterization of Biomolecules through Atomistic Simulations Guided by DEER Measurements. Structure 2019; 27:359-370.e12. [PMID: 30528595 PMCID: PMC6860373 DOI: 10.1016/j.str.2018.10.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 09/06/2018] [Accepted: 10/18/2018] [Indexed: 11/17/2022]
Abstract
Double electron-electron resonance (DEER) is a popular technique that exploits attached spin labels to probe the collective dynamics of biomolecules in a native environment. Like most spectroscopic approaches, DEER detects an ensemble of states accounting for biomolecular dynamics as well as the labels' intrinsic flexibility. Hence, the DEER data alone do not provide high-resolution structural information. To disentangle this variability, we introduce a minimally biased simulation method to sample a structural ensemble that reproduces multiple experimental signals within the uncertainty. In contrast to previous approaches, our method targets the raw data themselves, and thereby it brings forth an unbiased molecular interpretation of the experiments. After validation on the T4 lysozyme, we apply this technique to interpret recent DEER experiments on a membrane transporter binding protein (VcSiaP). The results highlight the large-scale conformational movement that occurs upon substrate binding and reveal that the unbound VcSiaP is more open in solution than the X-ray structure.
Collapse
Affiliation(s)
- Fabrizio Marinelli
- Theoretical Molecular Biophysics Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20814, USA.
| | - Giacomo Fiorin
- Theoretical Molecular Biophysics Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20814, USA
| |
Collapse
|
21
|
Gangi Setty T, Mowers JC, Hobbs AG, Maiya SP, Syed S, Munson RS, Apicella MA, Subramanian R. Molecular characterization of the interaction of sialic acid with the periplasmic binding protein from Haemophilus ducreyi. J Biol Chem 2018; 293:20073-20084. [PMID: 30315109 DOI: 10.1074/jbc.ra118.005151] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 10/11/2018] [Indexed: 12/18/2022] Open
Abstract
The primary role of bacterial periplasmic binding proteins is sequestration of essential metabolites present at a low concentration in the periplasm and making them available for active transporters that transfer these ligands into the bacterial cell. The periplasmic binding proteins (SiaPs) from the tripartite ATP-independent periplasmic (TRAP) transport system that transports mammalian host-derived sialic acids have been well studied from different pathogenic bacteria, including Haemophilus influenzae, Fusobacterium nucleatum, Pasteurella multocida, and Vibrio cholerae SiaPs bind the sialic acid N-acetylneuraminic acid (Neu5Ac) with nanomolar affinity by forming electrostatic and hydrogen-bonding interactions. Here, we report the crystal structure of a periplasmic binding protein (SatA) of the ATP-binding cassette (ABC) transport system from the pathogenic bacterium Haemophilus ducreyi The structure of Hd-SatA in the native form and sialic acid-bound forms (with Neu5Ac and N-glycolylneuraminic acid (Neu5Gc)), determined to 2.2, 1.5, and 2.5 Å resolutions, respectively, revealed a ligand-binding site that is very different from those of the SiaPs of the TRAP transport system. A structural comparison along with thermodynamic studies suggested that similar affinities are achieved in the two classes of proteins through distinct mechanisms, one enthalpically driven and the other entropically driven. In summary, our structural and thermodynamic characterization of Hd-SatA reveals that it binds sialic acids with nanomolar affinity and that this binding is an entropically driven process. This information is important for future structure-based drug design against this pathogen and related bacteria.
Collapse
Affiliation(s)
- Thanuja Gangi Setty
- From the Institute for Stem Cell Biology and Regenerative Medicine, GKVK Post, Bangalore 560065, India,; the University of Trans-Disciplinary Health Sciences and Technology (TDU), Bengaluru, Karnataka 560064, India
| | - Jonathan C Mowers
- the Departments of Biochemistry and Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Aaron G Hobbs
- the Departments of Biochemistry and Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Shubha P Maiya
- From the Institute for Stem Cell Biology and Regenerative Medicine, GKVK Post, Bangalore 560065, India
| | - Sanaa Syed
- From the Institute for Stem Cell Biology and Regenerative Medicine, GKVK Post, Bangalore 560065, India
| | - Robert S Munson
- the Center for Microbial Interface Biology, Ohio State University, Columbus, Ohio 43210, and
| | - Michael A Apicella
- Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Ramaswamy Subramanian
- From the Institute for Stem Cell Biology and Regenerative Medicine, GKVK Post, Bangalore 560065, India,; the Departments of Biochemistry and Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242.
| |
Collapse
|
22
|
Studying structure and function of membrane proteins with PELDOR/DEER spectroscopy – The crystallographers’ perspective. Methods 2018; 147:163-175. [DOI: 10.1016/j.ymeth.2018.03.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 02/20/2018] [Accepted: 03/01/2018] [Indexed: 12/16/2022] Open
|
23
|
North RA, Horne CR, Davies JS, Remus DM, Muscroft-Taylor AC, Goyal P, Wahlgren WY, Ramaswamy S, Friemann R, Dobson RCJ. "Just a spoonful of sugar...": import of sialic acid across bacterial cell membranes. Biophys Rev 2017; 10:219-227. [PMID: 29222808 DOI: 10.1007/s12551-017-0343-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 11/13/2017] [Indexed: 12/24/2022] Open
Abstract
Eukaryotic cell surfaces are decorated with a complex array of glycoconjugates that are usually capped with sialic acids, a large family of over 50 structurally distinct nine-carbon amino sugars, the most common member of which is N-acetylneuraminic acid. Once made available through the action of neuraminidases, bacterial pathogens and commensals utilise host-derived sialic acid by degrading it for energy or repurposing the sialic acid onto their own cell surface to camouflage the bacterium from the immune system. A functional sialic acid transporter has been shown to be essential for the uptake of sialic acid in a range of human bacterial pathogens and important for host colonisation and persistence. Here, we review the state-of-play in the field with respect to the molecular mechanisms by which these bio-nanomachines transport sialic acids across bacterial cell membranes.
Collapse
Affiliation(s)
- Rachel A North
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch, 8140, New Zealand
| | - Christopher R Horne
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch, 8140, New Zealand
| | - James S Davies
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch, 8140, New Zealand
| | - Daniela M Remus
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch, 8140, New Zealand
| | - Andrew C Muscroft-Taylor
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch, 8140, New Zealand
| | - Parveen Goyal
- Department of Chemistry and Molecular Biology, Biochemistry and Structural Biology, University of Gothenburg, Box 462, 40530, Gothenburg, Sweden.,Centre for Antibiotic Resistance Research (CARe) at University of Gothenburg, Box 440, 40530, Gothenburg, Sweden
| | - Weixiao Yuan Wahlgren
- Department of Chemistry and Molecular Biology, Biochemistry and Structural Biology, University of Gothenburg, Box 462, 40530, Gothenburg, Sweden.,Centre for Antibiotic Resistance Research (CARe) at University of Gothenburg, Box 440, 40530, Gothenburg, Sweden
| | - S Ramaswamy
- The Institute for Stem Cell Biology and Regenerative Medicine (InStem), G.K.V.K. Post Office, Bangalore, Karnataka, 560065, India
| | - Rosmarie Friemann
- Department of Chemistry and Molecular Biology, Biochemistry and Structural Biology, University of Gothenburg, Box 462, 40530, Gothenburg, Sweden. .,Centre for Antibiotic Resistance Research (CARe) at University of Gothenburg, Box 440, 40530, Gothenburg, Sweden.
| | - Renwick C J Dobson
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, P.O. Box 4800, Christchurch, 8140, New Zealand. .,Bio21 Molecular Science and Biotechnology Institute, Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, 3010, Australia.
| |
Collapse
|
24
|
Sialic acid acquisition in bacteria-one substrate, many transporters. Biochem Soc Trans 2017; 44:760-5. [PMID: 27284039 DOI: 10.1042/bst20160056] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Indexed: 11/17/2022]
Abstract
The sialic acids are a family of 9-carbon sugar acids found predominantly on the cell-surface glycans of humans and other animals within the Deuterostomes and are also used in the biology of a wide range of bacteria that often live in association with these animals. For many bacteria sialic acids are simply a convenient source of food, whereas for some pathogens they are also used in immune evasion strategies. Many bacteria that use sialic acids derive them from the environment and so are dependent on sialic acid uptake. In this mini-review I will describe the discovery and characterization of bacterial sialic acids transporters, revealing that they have evolved multiple times across multiple diverse families of transporters, including the ATP-binding cassette (ABC), tripartite ATP-independent periplasmic (TRAP), major facilitator superfamily (MFS) and sodium solute symporter (SSS) transporter families. In addition there is evidence for protein-mediated transport of sialic acids across the outer membrane of Gram negative bacteria, which can be coupled to periplasmic processing of different sialic acids to the most common form, β-D-N-acetylneuraminic acid (Neu5Ac) that is most frequently taken up into the cell.
Collapse
|
25
|
Glaenzer J, Peter MF, Thomas GH, Hagelueken G. PELDOR Spectroscopy Reveals Two Defined States of a Sialic Acid TRAP Transporter SBP in Solution. Biophys J 2017; 112:109-120. [PMID: 28076802 DOI: 10.1016/j.bpj.2016.12.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 11/29/2016] [Accepted: 12/08/2016] [Indexed: 10/20/2022] Open
Abstract
The tripartite ATP-independent periplasmic (TRAP) transporters are a widespread class of membrane transporters in bacteria and archaea. Typical substrates for TRAP transporters are organic acids including the sialic acid N-acetylneuraminic acid. The substrate binding proteins (SBP) of TRAP transporters are the best studied component and are responsible for initial high-affinity substrate binding. To better understand the dynamics of the ligand binding process, pulsed electron-electron double resonance (PELDOR, also known as DEER) spectroscopy was applied to study the conformational changes in the N-acetylneuraminic acid-specific SBP VcSiaP. The protein is the SBP of VcSiaPQM, a sialic acid TRAP transporter from Vibrio cholerae. Spin-labeled double-cysteine mutants of VcSiaP were analyzed in the substrate-bound and -free state and the measured distances were compared to available crystal structures. The data were compatible with two clear states only, which are consistent with the open and closed forms seen in TRAP SBP crystal structures. Substrate titration experiments demonstrated the transition of the population from one state to the other with no other observed forms. Mutants of key residues involved in ligand binding and/or proposed to be involved in domain closure were produced and the corresponding PELDOR experiments reveal important insights into the open-closed transition. The results are in excellent agreement with previous in vivo sialylation experiments. The structure of the spin-labeled Q54R1/L173R1 R125A mutant was solved at 2.1 Å resolution, revealing no significant changes in the protein structure. Thus, the loss of domain closure appears to be solely due to loss of binding. In conclusion, these data are consistent with TRAP SBPs undergoing a simple two-state transition from an open-unliganded to closed-liganded state during the transport cycle.
Collapse
Affiliation(s)
- Janin Glaenzer
- Institute for Physical & Theoretical Chemistry, University of Bonn, Bonn, Germany
| | - Martin F Peter
- Institute for Physical & Theoretical Chemistry, University of Bonn, Bonn, Germany
| | | | - Gregor Hagelueken
- Institute for Physical & Theoretical Chemistry, University of Bonn, Bonn, Germany.
| |
Collapse
|
26
|
Midgett CR, Almagro-Moreno S, Pellegrini M, Taylor RK, Skorupski K, Kull FJ. Bile salts and alkaline pH reciprocally modulate the interaction between the periplasmic domains of Vibrio cholerae ToxR and ToxS. Mol Microbiol 2017; 105:258-272. [PMID: 28464377 DOI: 10.1111/mmi.13699] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2017] [Indexed: 12/31/2022]
Abstract
ToxR is a transmembrane transcription factor that is essential for virulence gene expression and human colonization by Vibrio cholerae. ToxR requires its operon partner ToxS, a periplasmic integral membrane protein, for full activity. These two proteins are thought to interact through their respective periplasmic domains, ToxRp and ToxSp. In addition, ToxR is thought to be responsive to various environmental cues, such as bile salts and alkaline pH, but how these factors influence ToxR is not yet understood. Using NMR and reciprocal pull down assays, we present the first direct evidence that ToxR and ToxS physically interact. Furthermore, using NMR and DSF, it was shown that the bile salts cholate and chenodeoxycholate interact with purified ToxRp and destabilize it. Surprisingly, bile salt destabilization of ToxRp enhanced the interaction between ToxRp and ToxSp. In contrast, alkaline pH, which is one of the factors that leads to ToxR proteolysis, decreased the interaction between ToxRp and ToxSp. Taken together, these data suggest a model whereby bile salts or other detergents destabilize ToxR, increasing its interaction with ToxS to promote full ToxR activity. Subsequently, as V. cholerae alkalinizes its environment in late stationary phase, the interaction between the two proteins decreases, allowing ToxR proteolysis to proceed.
Collapse
Affiliation(s)
| | - Salvador Almagro-Moreno
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, 32816, USA
| | - Maria Pellegrini
- Department of Chemistry, Dartmouth College, Hanover, NH, 03755, USA
| | - Ronald K Taylor
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA
| | - Karen Skorupski
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA
| | - F Jon Kull
- Department of Chemistry, Dartmouth College, Hanover, NH, 03755, USA
| |
Collapse
|
27
|
Jeschke G. The Making and Breaking of a Substrate Trap. Biophys J 2017; 112:1-2. [DOI: 10.1016/j.bpj.2016.12.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 12/08/2016] [Indexed: 10/20/2022] Open
|
28
|
Lewis AL, Robinson LS, Agarwal K, Lewis WG. Discovery and characterization of de novo sialic acid biosynthesis in the phylum Fusobacterium. Glycobiology 2016; 26:1107-1119. [PMID: 27613803 DOI: 10.1093/glycob/cww068] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 06/15/2016] [Accepted: 06/16/2016] [Indexed: 12/15/2022] Open
Abstract
Sialic acids are nine-carbon backbone carbohydrates found in prominent outermost positions of glycosylated molecules in mammals. Mimicry of sialic acid (N-acetylneuraminic acid, Neu5Ac) enables some pathogenic bacteria to evade host defenses. Fusobacterium nucleatum is a ubiquitous oral bacterium also linked with invasive infections throughout the body. We employed multidisciplinary approaches to test predictions that F. nucleatum engages in de novo synthesis of sialic acids. Here we show that F. nucleatum sbsp. polymorphum ATCC10953 NeuB (putative Neu5Ac synthase) restores Neu5Ac synthesis to an Escherichia coli neuB mutant. Moreover, purified F. nucleatum NeuB participated in synthesis of Neu5Ac from N-acetylmannosamine and phosphoenolpyruvate in vitro Further studies support the interpretation that F. nucleatum ATCC10953 NeuA encodes a functional CMP-sialic acid synthetase and suggest that it may also contain a C-terminal sialic acid O-acetylesterase. We also performed BLAST queries of F. nucleatum genomes, revealing that only 4/31 strains encode a complete pathway for de novo Neu5Ac synthesis. Biochemical studies including mass spectrometry were consistent with the bioinformatic predictions, showing that F. nucleatum ATCC10953 synthesizes high levels of Neu5Ac, whereas ATCC23726 and ATCC25586 do not express detectable levels above background. While there are a number of examples of sialic acid mimicry in other phyla, these experiments provide the first biochemical and genetic evidence that a member of the phylum Fusobacterium can engage in de novo Neu5Ac synthesis.
Collapse
Affiliation(s)
- Amanda L Lewis
- Department of Molecular Microbiology .,Department of Obstetrics and Gynecology
| | | | | | - Warren G Lewis
- Department of Medicine, Center for Women's Infectious Disease Research, 660 South Euclid Ave, Washington University School of Medicine, St. Louis, MO, USA
| |
Collapse
|
29
|
Pal KB, Sarkar V, Mukhopadhyay B. Hydrogen bonding-induced conformational change in a crystalline sugar derivative. CrystEngComm 2016. [DOI: 10.1039/c5ce01893e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We report crystallographic evidence of the change of a regular chair conformation to a skew boat conformation in a partially protected sugar derivative.
Collapse
Affiliation(s)
- Kumar Bhaskar Pal
- Department of Chemical Sciences
- Indian Institute of Science Education and Research (IISER) Kolkata
- Mohanpur, India
| | - Vikramjit Sarkar
- Department of Chemical Sciences
- Indian Institute of Science Education and Research (IISER) Kolkata
- Mohanpur, India
| | - Balaram Mukhopadhyay
- Department of Chemical Sciences
- Indian Institute of Science Education and Research (IISER) Kolkata
- Mohanpur, India
| |
Collapse
|