1
|
Shaw AL, Suresh S, Parson MAH, Harris NJ, Jenkins ML, Yip CK, Burke JE. Structure of calcineurin bound to PI4KA reveals dual interface in both PI4KA and FAM126A. Structure 2024:S0969-2126(24)00324-1. [PMID: 39216471 DOI: 10.1016/j.str.2024.08.007] [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: 04/16/2024] [Revised: 07/02/2024] [Accepted: 08/06/2024] [Indexed: 09/04/2024]
Abstract
Phosphatidylinositol 4-kinase alpha (PI4KA) maintains the phosphatidylinositol 4-phosphate (PI4P) and phosphatidylserine pools of the plasma membrane. A key regulator of PI4KA is its association into a complex with TTC7 and FAM126 proteins. This complex can be regulated by the CNAβ1 isoform of the phosphatase calcineurin. We previously identified that CNAβ1 directly binds to FAM126A. Here, we report a cryoelectron microscopic (cryo-EM) structure of a truncated PI4KA complex bound to calcineurin, revealing a unique direct interaction between PI4KA and calcineurin. Hydrogen deuterium exchange mass spectrometry (HDX-MS) and computational analysis show that calcineurin forms a complex with an evolutionarily conserved IKISVT sequence in PI4KA's horn domain. We also characterized conserved LTLT and PSISIT calcineurin binding sequences in the C terminus of FAM126A. These dual sites in PI4KA and FAM126A are both in close proximity to phosphorylation sites in the PI4KA complex, suggesting key roles of calcineurin-regulated phosphosites in PI4KA regulation. This work reveals novel insight into how calcineurin can regulate PI4KA activity.
Collapse
Affiliation(s)
- Alexandria L Shaw
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada; Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Sushant Suresh
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Matthew A H Parson
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Noah J Harris
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Meredith L Jenkins
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Calvin K Yip
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - John E Burke
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada; Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada.
| |
Collapse
|
2
|
De Filippis V, Acquasaliente L, Pierangelini A, Marin O. Chemical Synthesis and Structure-Activity Relationship Studies of the Coagulation Factor Xa Inhibitor Tick Anticoagulant Peptide from the Hematophagous Parasite Ornithodoros moubata. Biomimetics (Basel) 2024; 9:485. [PMID: 39194464 DOI: 10.3390/biomimetics9080485] [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: 07/10/2024] [Revised: 07/29/2024] [Accepted: 08/05/2024] [Indexed: 08/29/2024] Open
Abstract
Tick Anticoagulant Peptide (TAP), a 60-amino acid protein from the soft tick Ornithodoros moubata, inhibits activated coagulation factor X (fXa) with almost absolute specificity. Despite TAP and Bovine Pancreatic Trypsin Inhibitor (BPTI) (i.e., the prototype of the Kunitz-type protease inhibitors) sharing a similar 3D fold and disulphide bond topology, they have remarkably different amino acid sequence (only ~24% sequence identity), thermal stability, folding pathways, protease specificity, and even mechanism of protease inhibition. Here, fully active and correctly folded TAP was produced in reasonably high yields (~20%) by solid-phase peptide chemical synthesis and thoroughly characterised with respect to its chemical identity, disulphide pairing, folding kinetics, conformational dynamics, and fXa inhibition. The versatility of the chemical synthesis was exploited to perform structure-activity relationship studies on TAP by incorporating non-coded amino acids at positions 1 and 3 of the inhibitor. Using Hydrogen-Deuterium Exchange Mass Spectrometry, we found that TAP has a remarkably higher conformational flexibility compared to BPTI, and propose that these different dynamics could impact the different folding pathway and inhibition mechanisms of TAP and BPTI. Hence, the TAP/BPTI pair represents a nice example of divergent evolution, while the relative facility of TAP synthesis could represent a good starting point to design novel synthetic analogues with improved pharmacological profiles.
Collapse
Affiliation(s)
- Vincenzo De Filippis
- Laboratory of Protein Chemistry & Molecular Haematology, Department of Pharmaceutical and Pharmacological Sciences, School of Medicine, University of Padova, Via F. Marzolo 5, 35131 Padua, Italy
| | - Laura Acquasaliente
- Laboratory of Protein Chemistry & Molecular Haematology, Department of Pharmaceutical and Pharmacological Sciences, School of Medicine, University of Padova, Via F. Marzolo 5, 35131 Padua, Italy
| | - Andrea Pierangelini
- Laboratory of Protein Chemistry & Molecular Haematology, Department of Pharmaceutical and Pharmacological Sciences, School of Medicine, University of Padova, Via F. Marzolo 5, 35131 Padua, Italy
| | - Oriano Marin
- Department of Biomedical Sciences, School of Medicine, University of Padova, Via Trieste 75, 35121 Padua, Italy
| |
Collapse
|
3
|
Wales TE, Pajak A, Roeselová A, Shivakumaraswamy S, Howell S, Kjær S, Hartl FU, Engen JR, Balchin D. Resolving chaperone-assisted protein folding on the ribosome at the peptide level. Nat Struct Mol Biol 2024:10.1038/s41594-024-01355-x. [PMID: 38987455 DOI: 10.1038/s41594-024-01355-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 06/17/2024] [Indexed: 07/12/2024]
Abstract
Protein folding in vivo begins during synthesis on the ribosome and is modulated by molecular chaperones that engage the nascent polypeptide. How these features of protein biogenesis influence the maturation pathway of nascent proteins is incompletely understood. Here, we use hydrogen-deuterium exchange mass spectrometry to define, at peptide resolution, the cotranslational chaperone-assisted folding pathway of Escherichia coli dihydrofolate reductase. The nascent polypeptide folds along an unanticipated pathway through structured intermediates not populated during refolding from denaturant. Association with the ribosome allows these intermediates to form, as otherwise destabilizing carboxy-terminal sequences remain confined in the ribosome exit tunnel. Trigger factor binds partially folded states without disrupting their structure, and the nascent chain is poised to complete folding immediately upon emergence of the C terminus from the exit tunnel. By mapping interactions between the nascent chain and ribosomal proteins, we trace the path of the emerging polypeptide during synthesis. Our work reveals new mechanisms by which cellular factors shape the conformational search for the native state.
Collapse
Affiliation(s)
- Thomas E Wales
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, USA
| | - Aleksandra Pajak
- Protein Biogenesis Laboratory, The Francis Crick Institute, London, UK
| | - Alžběta Roeselová
- Protein Biogenesis Laboratory, The Francis Crick Institute, London, UK
| | | | - Steven Howell
- Proteomics Science Technology Platform, The Francis Crick Institute, London, UK
| | - Svend Kjær
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - F Ulrich Hartl
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - John R Engen
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, USA.
| | - David Balchin
- Protein Biogenesis Laboratory, The Francis Crick Institute, London, UK.
| |
Collapse
|
4
|
Haynes CA, Keppel TR, Mekonnen B, Osman SH, Zhou Y, Woolfitt AR, Baudys J, Barr JR, Wang D. Inclusion of deuterated glycopeptides provides increased sequence coverage in hydrogen/deuterium exchange mass spectrometry analysis of SARS-CoV-2 spike glycoprotein. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2024; 38:e9690. [PMID: 38355883 PMCID: PMC10871554 DOI: 10.1002/rcm.9690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/28/2023] [Accepted: 12/03/2023] [Indexed: 02/16/2024]
Abstract
RATIONALE Hydrogen/deuterium exchange mass spectrometry (HDX-MS) can provide precise analysis of a protein's conformational dynamics across varied states, such as heat-denatured versus native protein structures, localizing regions that are specifically affected by such conditional changes. Maximizing protein sequence coverage provides high confidence that regions of interest were located by HDX-MS, but one challenge for complete sequence coverage is N-glycosylation sites. The deuteration of peptides post-translationally modified by asparagine-bound glycans (glycopeptides) has not always been identified in previous reports of HDX-MS analyses, causing significant sequence coverage gaps in heavily glycosylated proteins and uncertainty in structural dynamics in many regions throughout a glycoprotein. METHODS We detected deuterated glycopeptides with a Tribrid Orbitrap Eclipse mass spectrometer performing data-dependent acquisition. An MS scan was used to identify precursor ions; if high-energy collision-induced dissociation MS/MS of the precursor indicated oxonium ions diagnostic for complex glycans, then electron transfer low-energy collision-induced dissociation MS/MS scans of the precursor identified the modified asparagine residue and the glycan's mass. As in traditional HDX-MS, the identified glycopeptides were then analyzed at the MS level in samples labeled with D2 O. RESULTS We report HDX-MS analysis of the SARS-CoV-2 spike protein ectodomain in its trimeric prefusion form, which has 22 predicted N-glycosylation sites per monomer, with and without heat treatment. We identified glycopeptides and calculated their average isotopic mass shifts from deuteration. Inclusion of the deuterated glycopeptides increased sequence coverage of spike ectodomain from 76% to 84%, demonstrated that glycopeptides had been deuterated, and improved confidence in results localizing structural rearrangements. CONCLUSION Inclusion of deuterated glycopeptides improves the analysis of the conformational dynamics of glycoproteins such as viral surface antigens and cellular receptors.
Collapse
Affiliation(s)
- Christopher A Haynes
- Structure Laboratory, Clinical Chemistry Branch, Division of Laboratory Sciences, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Theodore R Keppel
- Structure Laboratory, Clinical Chemistry Branch, Division of Laboratory Sciences, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Betlehem Mekonnen
- Structure Laboratory, Clinical Chemistry Branch, Division of Laboratory Sciences, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Sarah H Osman
- Structure Laboratory, Clinical Chemistry Branch, Division of Laboratory Sciences, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Yu Zhou
- Structure Laboratory, Clinical Chemistry Branch, Division of Laboratory Sciences, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Adrian R Woolfitt
- Structure Laboratory, Clinical Chemistry Branch, Division of Laboratory Sciences, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Jakub Baudys
- Structure Laboratory, Clinical Chemistry Branch, Division of Laboratory Sciences, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - John R Barr
- Structure Laboratory, Clinical Chemistry Branch, Division of Laboratory Sciences, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Dongxia Wang
- Structure Laboratory, Clinical Chemistry Branch, Division of Laboratory Sciences, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| |
Collapse
|
5
|
Salmas R, Borysik AJ. Deep Learning Enables Automatic Correction of Experimental HDX-MS Data with Applications in Protein Modeling. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:197-204. [PMID: 38262924 PMCID: PMC10853964 DOI: 10.1021/jasms.3c00285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 12/24/2023] [Accepted: 01/04/2024] [Indexed: 01/25/2024]
Abstract
Observed mass shifts associated with deuterium incorporation in hydrogen-deuterium exchange mass spectrometry (HDX-MS) frequently deviate from the initial signals due to back and forward exchange. In typical HDX-MS experiments, the impact of these disparities on data interpretation is generally low because relative and not absolute mass changes are investigated. However, for more advanced data processing including optimization, experimental error correction is imperative for accurate results. Here the potential for automatic HDX-MS data correction using models generated by deep neural networks is demonstrated. A multilayer perceptron (MLP) is used to learn a mapping between uncorrected HDX-MS data and data with mass shifts corrected for back and forward exchange. The model is rigorously tested at various levels including peptide level mass changes, residue level protection factors following optimization, and ability to correctly identify native protein folds using HDX-MS guided protein modeling. AI is shown to demonstrate considerable potential for amending HDX-MS data and improving fidelity across all levels. With access to big data, online tools may eventually be able to predict corrected mass shifts in HDX-MS profiles. This should improve throughput in workflows that require the reporting of real mass changes as well as allow retrospective correction of historic profiles to facilitate new discoveries with these data.
Collapse
Affiliation(s)
| | - Antoni J. Borysik
- Department of Chemistry, King’s
College London, Britannia House, London SE1 1DB, U.K.
| |
Collapse
|
6
|
Wan N, Hong Z, Parson MAH, Korfhage JL, Burke JE, Melia TJ, Reinisch KM. Spartin-mediated lipid transfer facilitates lipid droplet turnover. Proc Natl Acad Sci U S A 2024; 121:e2314093121. [PMID: 38190532 PMCID: PMC10801920 DOI: 10.1073/pnas.2314093121] [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: 08/15/2023] [Accepted: 12/01/2023] [Indexed: 01/10/2024] Open
Abstract
Lipid droplets (LDs) are organelles critical for energy storage and membrane lipid homeostasis, whose number and size are carefully regulated in response to cellular conditions. The molecular mechanisms underlying lipid droplet biogenesis and degradation, however, are not well understood. The Troyer syndrome protein spartin (SPG20) supports LD delivery to autophagosomes for turnover via lipophagy. Here, we characterize spartin as a lipid transfer protein whose transfer ability is required for LD degradation. Spartin copurifies with phospholipids and neutral lipids from cells and transfers phospholipids in vitro via its senescence domain. A senescence domain truncation that impairs lipid transfer in vitro also impairs LD turnover in cells while not affecting spartin association with either LDs or autophagosomes, supporting that spartin's lipid transfer ability is physiologically relevant. Our data indicate a role for spartin-mediated lipid transfer in LD turnover.
Collapse
Affiliation(s)
- Neng Wan
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06520
| | - Zhouping Hong
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06520
| | - Matthew A. H. Parson
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BCV8W2Y2, Canada
| | - Justin L. Korfhage
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06520
| | - John E. Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BCV8W2Y2, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BCV6T 1Z3, Canada
| | - Thomas J. Melia
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06520
| | - Karin M. Reinisch
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT06520
| |
Collapse
|
7
|
Acquasaliente L, Pierangelini A, Pagotto A, Pozzi N, De Filippis V. From haemadin to haemanorm: Synthesis and characterization of full-length haemadin from the leech Haemadipsa sylvestris and of a novel bivalent, highly potent thrombin inhibitor (haemanorm). Protein Sci 2023; 32:e4825. [PMID: 37924304 PMCID: PMC10683372 DOI: 10.1002/pro.4825] [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: 06/16/2023] [Revised: 10/25/2023] [Accepted: 10/27/2023] [Indexed: 11/06/2023]
Abstract
Hirudin from Hirudo medicinalis is a bivalent α-Thrombin (αT) inhibitor, targeting the enzyme active site and exosite-I, and is currently used in anticoagulant therapy along with its simplified analogue hirulog. Haemadin, a small protein (57 amino acids) isolated from the land-living leech Haemadipsa sylvestris, selectively inhibits αT with a potency identical to that of recombinant hirudin (KI = 0.2 pM), with which it shares a common disulfide topology and overall fold. At variance with hirudin, haemadin targets exosite-II and therefore (besides the free protease) it also blocks thrombomodulin-bound αT without inhibiting the active intermediate meizothrombin, thus offering potential advantages over hirudin. Here, we produced in reasonably high yields and pharmaceutical purity (>98%) wild-type haemadin and the oxidation resistant Met5 → nor-Leucine analogue, both inhibiting αT with a KI of 0.2 pM. Thereafter, we used site-directed mutagenesis, spectroscopic, ligand-displacement, and Hydrogen/Deuterium Exchange-Mass Spectrometry techniques to map the αT regions relevant for the interaction with full-length haemadin and with the synthetic N- and C-terminal peptides Haem(1-10) and Haem(45-57). Haem(1-10) competitively binds to/inhibits αT active site (KI = 1.9 μM) and its potency was enhanced by 10-fold after Phe3 → β-Naphthylalanine exchange. Conversely to full-length haemadin, haem(45-57) displays intrinsic affinity for exosite-I (KD = 1.6 μM). Hence, we synthesized a peptide in which the sequences 1-9 and 45-57 were joined together through a 3-Glycine spacer to yield haemanorm, a highly potent (KI = 0.8 nM) inhibitor targeting αT active site and exosite-I. Haemanorm can be regarded as a novel class of hirulog-like αT inhibitors with potential pharmacological applications.
Collapse
Affiliation(s)
- Laura Acquasaliente
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
| | - Andrea Pierangelini
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
| | - Anna Pagotto
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
| | - Nicola Pozzi
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
- Department of Biochemistry and Molecular Biology, Edward A. Doisy Research CenterSaint Louis UniversitySt. LouisMissouriUSA
| | - Vincenzo De Filippis
- Laboratory of Protein Chemistry & Molecular Hematology, Department of Pharmaceutical and Pharmacological Sciences, School of MedicineUniversity of PadovaPaduaItaly
| |
Collapse
|
8
|
Wan N, Hong Z, Parson MAH, Korfhage J, Burke JE, Melia TJ, Reinisch KM. Spartin-mediated lipid transfer facilitates lipid droplet turnover. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.29.569220. [PMID: 38076959 PMCID: PMC10705495 DOI: 10.1101/2023.11.29.569220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
Lipid droplets (LDs) are organelles critical for energy storage and membrane lipid homeostasis, whose number and size are carefully regulated in response to cellular conditions. The molecular mechanisms underlying lipid droplet biogenesis and degradation, however, are not well understood. The Troyer syndrome protein spartin (SPG20) supports LD delivery to autophagosomes for turnover via lipophagy. Here, we characterize spartin as a lipid transfer protein whose transfer ability is required for LD degradation. Spartin co-purifies with phospholipids and neutral lipids from cells and transfers phospholipids in vitro via its senescence domain. A senescence domain truncation that impairs lipid transfer in vitro also impairs LD turnover in cells while not affecting spartin association with either LDs or autophagosomes, supporting that spartin's lipid transfer ability is physiologically relevant. Our data indicate a role for spartin-mediated lipid transfer in LD turnover.
Collapse
Affiliation(s)
- Neng Wan
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Zhouping Hong
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Matthew A. H. Parson
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada V8W2Y2
| | - Justin Korfhage
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - John E. Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada V8W2Y2
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada V6T 1Z3
| | - Thomas J. Melia
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Karin M. Reinisch
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06520, USA
| |
Collapse
|
9
|
Russell Lewis B, Uddin MR, Moniruzzaman M, Kuo KM, Higgins AJ, Shah LMN, Sobott F, Parks JM, Hammerschmid D, Gumbart JC, Zgurskaya HI, Reading E. Conformational restriction shapes the inhibition of a multidrug efflux adaptor protein. Nat Commun 2023; 14:3900. [PMID: 37463890 PMCID: PMC10354078 DOI: 10.1038/s41467-023-39615-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 06/15/2023] [Indexed: 07/20/2023] Open
Abstract
Membrane efflux pumps play a major role in bacterial multidrug resistance. The tripartite multidrug efflux pump system from Escherichia coli, AcrAB-TolC, is a target for inhibition to lessen resistance development and restore antibiotic efficacy, with homologs in other ESKAPE pathogens. Here, we rationalize a mechanism of inhibition against the periplasmic adaptor protein, AcrA, using a combination of hydrogen/deuterium exchange mass spectrometry, cellular efflux assays, and molecular dynamics simulations. We define the structural dynamics of AcrA and find that an inhibitor can inflict long-range stabilisation across all four of its domains, whereas an interacting efflux substrate has minimal effect. Our results support a model where an inhibitor forms a molecular wedge within a cleft between the lipoyl and αβ barrel domains of AcrA, diminishing its conformational transmission of drug-evoked signals from AcrB to TolC. This work provides molecular insights into multidrug adaptor protein function which could be valuable for developing antimicrobial therapeutics.
Collapse
Affiliation(s)
- Benjamin Russell Lewis
- Department of Chemistry, King's College London, Britannia House, 7 Trinity Street, London, SE1 1DB, UK
| | - Muhammad R Uddin
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, 73019, USA
| | - Mohammad Moniruzzaman
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, 73019, USA
| | - Katie M Kuo
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 837 State Street NW, Atlanta, GA, 30332, USA
| | - Anna J Higgins
- School of Molecular and Cellular Biology & Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Laila M N Shah
- Department of Chemistry, King's College London, Britannia House, 7 Trinity Street, London, SE1 1DB, UK
| | - Frank Sobott
- School of Molecular and Cellular Biology & Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - Jerry M Parks
- Bioscience Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37831, USA
| | - Dietmar Hammerschmid
- Department of Chemistry, King's College London, Britannia House, 7 Trinity Street, London, SE1 1DB, UK
| | - James C Gumbart
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 837 State Street NW, Atlanta, GA, 30332, USA.
- School of Physics, Georgia Institute of Technology, 837 State Street NW, Atlanta, GA, 30332, USA.
| | - Helen I Zgurskaya
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, 73019, USA.
| | - Eamonn Reading
- Department of Chemistry, King's College London, Britannia House, 7 Trinity Street, London, SE1 1DB, UK.
| |
Collapse
|
10
|
Peterle D, DePice D, Wales TE, Engen JR. Increase the flow rate and improve hydrogen deuterium exchange mass spectrometry. J Chromatogr A 2023; 1689:463742. [PMID: 36586285 PMCID: PMC9872520 DOI: 10.1016/j.chroma.2022.463742] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/15/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022]
Abstract
Reversed-phase peptide separation in hydrogen deuterium exchange (HDX) mass spectrometry (MS) must be done with conditions where the back exchange is the slowest possible, the so-called quench conditions of low pH and low temperature. To retain maximum deuterium, separation must also be done as quickly as possible. The low temperature (0 °C) of quench conditions complicates the separation and leads primarily to a reduction in separation quality and an increase in chromatographic backpressure. To improve the separation in HDX MS, one could use a longer gradient, smaller particles, a different separation mechanism (for example, capillary electrophoresis), or multi-dimensional separations such as combining ion mobility separation with reversed-phase separation. Another way to improve separations under HDX MS quench conditions is to use a higher flow rate where separation efficiency at 0 °C is more ideal. Higher flow rates, however, require chromatographic systems (both pumps and fittings) with higher backpressure limits. We tested what improvements could be realized with a commercial UPLC/UHPLC system capable of ∼20,000 psi backpressure. We found that a maximum flow rate of 225 µL/min (using a 1 × 50 mm column packed with 1.8 µm particles) was possible and that higher flow rate clearly led to higher peak capacity. HDX MS analysis of both simple and particularly complex samples improved, permitting both shorter separation time, if desired, and providing more deuterium recovery.
Collapse
Affiliation(s)
- Daniele Peterle
- Department of Chemistry and Chemical Biology, Northeastern University, Mailstop 412 TF, 360 Huntington Avenue, Boston, MA 02115, United States
| | - David DePice
- Department of Chemistry and Chemical Biology, Northeastern University, Mailstop 412 TF, 360 Huntington Avenue, Boston, MA 02115, United States
| | - Thomas E Wales
- Department of Chemistry and Chemical Biology, Northeastern University, Mailstop 412 TF, 360 Huntington Avenue, Boston, MA 02115, United States
| | - John R Engen
- Department of Chemistry and Chemical Biology, Northeastern University, Mailstop 412 TF, 360 Huntington Avenue, Boston, MA 02115, United States.
| |
Collapse
|
11
|
Investigating how intrinsically disordered regions contribute to protein function using HDX-MS. Biochem Soc Trans 2022; 50:1607-1617. [DOI: 10.1042/bst20220206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 11/11/2022] [Accepted: 11/14/2022] [Indexed: 12/02/2022]
Abstract
A large amount of the human proteome is composed of highly dynamic regions that do not adopt a single static conformation. These regions are defined as intrinsically disordered, and they are found in a third of all eukaryotic proteins. They play instrumental roles in many aspects of protein signaling, but can be challenging to characterize by biophysical methods. Intriguingly, many of these regions can adopt stable secondary structure upon interaction with a variety of binding partners, including proteins, lipids, and ligands. This review will discuss the application of Hydrogen-deuterium exchange mass spectrometry (HDX-MS) as a powerful biophysical tool that is particularly well suited for structural and functional characterization of intrinsically disordered regions in proteins. A focus will be on the theory of hydrogen exchange, and its practical application to identify disordered regions, as well as characterize how they participate in protein–protein and protein–membrane interfaces. A particular emphasis will be on how HDX-MS data can be presented specifically tailored for analysis of intrinsically disordered regions, as well as the technical aspects that are critical to consider when designing HDX-MS experiments for proteins containing intrinsically disordered regions.
Collapse
|
12
|
Tajoddin NN, Konermann L. Structural Dynamics of a Thermally Stressed Monoclonal Antibody Characterized by Temperature-Dependent H/D Exchange Mass Spectrometry. Anal Chem 2022; 94:15499-15509. [DOI: 10.1021/acs.analchem.2c03931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nastaran N. Tajoddin
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| |
Collapse
|
13
|
Fundamentals of HDX-MS. Essays Biochem 2022; 67:301-314. [PMID: 36251047 PMCID: PMC10070489 DOI: 10.1042/ebc20220111] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 11/17/2022]
Abstract
Hydrogen deuterium exchange mass spectrometry (HDX-MS) is becoming part of the standard repertoire of techniques used by molecular biologists to investigate protein structure and dynamics. This is partly due to the increased use of automation in all stages of the technique and its versatility of application-many proteins that present challenges with techniques such as X-ray crystallography and cryoelectron microscopy are amenable to investigation with HDX-MS. The present review is aimed at scientists who are curious about the technique, and how it may aid their research. It describes the fundamental basis of solvent exchange, the basics of a standard HDX-MS experiment, as well as highlighting emerging novel experimental advances, which point to where the field is heading.
Collapse
|