1
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Zhao W, Debnath D, Gautam I, Fernando LD, Wang T. Charting the solid-state NMR signals of polysaccharides: A database-driven roadmap. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:298-309. [PMID: 37724740 DOI: 10.1002/mrc.5397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 09/01/2023] [Accepted: 09/07/2023] [Indexed: 09/21/2023]
Abstract
Solid-state nuclear magnetic resonance (ssNMR) measurements of intact cell walls and cellular samples often generate spectra that are difficult to interpret due to the presence of many coexisting glycans and the structural polymorphism observed in native conditions. To overcome this analytical challenge, we present a statistical approach for analyzing carbohydrate signals using high-resolution ssNMR data indexed in a carbohydrate database. We generate simulated spectra to demonstrate the chemical shift dispersion and compare this with experimental data to facilitate the identification of important fungal and plant polysaccharides, such as chitin and glucans in fungi and cellulose, hemicellulose, and pectic polymers in plants. We also demonstrate that chemically distinct carbohydrates from different organisms may produce almost identical signals, highlighting the need for high-resolution spectra and validation of resonance assignments. Our study provides a means to differentiate the characteristic signals of major carbohydrates and allows us to summarize currently undetected polysaccharides in plants and fungi, which may inspire future investigations.
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Affiliation(s)
- Wancheng Zhao
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Debkumar Debnath
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Isha Gautam
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Liyanage D Fernando
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Tuo Wang
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
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2
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Sani MA, Rajput S, Keizer DW, Separovic F. NMR techniques for investigating antimicrobial peptides in model membranes and bacterial cells. Methods 2024; 224:10-20. [PMID: 38295893 DOI: 10.1016/j.ymeth.2024.01.012] [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: 10/31/2023] [Revised: 01/07/2024] [Accepted: 01/08/2024] [Indexed: 02/05/2024] Open
Abstract
AMPs are short, mainly cationic membrane-active peptides found in all living organism. They perform diverse roles including signaling and acting as a line of defense against bacterial infections. AMPs have been extensively investigated as templates to facilitate the development of novel antimicrobial therapeutics. Understanding the interplay between these membrane-active peptides and the lipid membranes is considered to be a significant step in elucidating the specific mechanism of action of AMPs against prokaryotic and eukaryotic cells to aid the development of new therapeutics. In this review, we have provided a brief overview of various NMR techniques commonly used for studying AMP structure and AMP-membrane interactions in model membranes and whole cells.
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Affiliation(s)
- Marc-Antoine Sani
- Bio21 Institute, University of Melbourne, Melbourne, VIC 3010, Australia.
| | - Sunnia Rajput
- Bio21 Institute, University of Melbourne, Melbourne, VIC 3010, Australia
| | - David W Keizer
- Bio21 Institute, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Frances Separovic
- Bio21 Institute, University of Melbourne, Melbourne, VIC 3010, Australia; School of Chemistry, University of Melbourne, Melbourne, VIC 3010, Australia
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3
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Byeon CH, Kinney T, Saricayir H, Srinivasa S, Wells MK, Kim W, Akbey Ü. Tapping into the native Pseudomonas bacterial biofilm structure by high-resolution multidimensional solid-state NMR. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 357:107587. [PMID: 37984030 PMCID: PMC10913148 DOI: 10.1016/j.jmr.2023.107587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 10/19/2023] [Accepted: 11/03/2023] [Indexed: 11/22/2023]
Abstract
We present a multidimensional magic-angle spinning (MAS) solid-state NMR (ssNMR) study to characterize native Pseudomonas fluorescens colony biofilms at natural abundance without isotope-labelling. By using a high-resolution INEPT-based 2D 1H-13C ssNMR spectrum and thorough peak deconvolution at the 1D ssNMR spectra, approximately 80/134 (in 1D/2D) distinct biofilm chemical sites were identified. We compared CP and INEPT 13C ssNMR spectra to differentiate signals originating from the mobile and rigid fractions of the biofilm, and qualitatively determined dynamical changes by comparing CP buildup behaviors. Protein and polysaccharide signals were differentiated and identified by utilizing FapC protein signals as a template, a biofilm forming functional amyloid from Pseudomonas. We identified several biofilm polysaccharide species such as glucose, mannan, galactose, heptose, rhamnan, fucose and N-acylated mannuronic acid by using 1H and 13C chemical shifts obtained from the 2D spectrum. To our knowledge, this study marks the first high-resolution multidimensional ssNMR characterization of a native bacterial biofilm. Our experimental pipeline can be readily applied to other in vitro biofilm model systems and natural biofilms and holds the promise of making a substantial impact on biofilm research, fostering new ideas and breakthroughs to aid in the development of strategic approaches to combat infections caused by biofilm-forming bacteria.
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Affiliation(s)
- Chang-Hyeock Byeon
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, PA 15261, United States
| | - Ted Kinney
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, PA 15261, United States
| | - Hakan Saricayir
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, PA 15261, United States
| | - Sadhana Srinivasa
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282, United States
| | - Meghan K Wells
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282, United States
| | - Wook Kim
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282, United States
| | - Ümit Akbey
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, PA 15261, United States.
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4
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Liu X, Brčić J, Cassell GH, Cegelski L. CPMAS NMR platform for direct compositional analysis of mycobacterial cell-wall complexes and whole cells. JOURNAL OF MAGNETIC RESONANCE OPEN 2023; 16-17:100127. [PMID: 38125335 PMCID: PMC10732466 DOI: 10.1016/j.jmro.2023.100127] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Tuberculosis and non-tuberculosis mycobacterial infections are rising each year and often result in chronic incurable disease. Important antibiotics target cell-wall biosynthesis, yet some mycobacteria are alarmingly resistant or tolerant to currently available antibiotics. This resistance is often attributed to assumed differences in composition of the complex cell wall of different mycobacterial strains and species. However, due to the highly crosslinked and insoluble nature of mycobacterial cell walls, direct comparative determinations of cell-wall composition pose a challenge to analysis through conventional biochemical analyses. We introduce an approach to directly observe the chemical composition of mycobacterial cell walls using solid-state NMR spectroscopy. 13C CPMAS spectra are provided of individual components (peptidoglycan, arabinogalactan, and mycolic acids) and of in situ cell-wall complexes. We assigned the spectroscopic contributions of each component in the cell-wall spectrum. We uncovered a higher arabinogalactan-to-peptidoglycan ratio in the cell wall of M. abscessus, an organism noted for its antibiotic resistance, relative to M. smegmatis. Furthermore, differentiating influences of different types of cell-wall targeting antibiotics were observed in spectra of antibiotic-treated whole cells. This platform will be of value in evaluating cell-wall composition and antibiotic activity among different mycobacteria and in considering the most effective combination treatment regimens.
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Affiliation(s)
- Xinyu Liu
- Department of Chemistry, Stanford University, CA 94305, United States
| | - Jasna Brčić
- Department of Chemistry, Stanford University, CA 94305, United States
| | - Gail H. Cassell
- PAI Life Sciences Inc, Seattle WA 98102, United States
- Department of Global Health and Social Medicine, Harvard Medical School, Boston, MA 02115, United States
| | - Lynette Cegelski
- Department of Chemistry, Stanford University, CA 94305, United States
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5
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Byeon CH, Kinney T, Saricayir H, Srinivasa S, Wells MK, Kim W, Akbey Ü. Tapping into the native Pseudomonas Bacterial Biofilm Structure by High-Resolution 1D and 2D MAS solid-state NMR. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.02.560490. [PMID: 37873242 PMCID: PMC10592892 DOI: 10.1101/2023.10.02.560490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
We present a high-resolution 1D and 2D magic-angle spinning (MAS) solid-state NMR (ssNMR) study to characterize native Pseudomonas fluorescens colony biofilms at natural abundance without isotope-labelling. By using a high-resolution INEPT-based 2D 1 H- 13 C ssNMR spectrum and thorough peak deconvolution approach at the 1D ssNMR spectra, approximately 80/134 (in 1D/2D) distinct biofilm chemical sites were identified. We compared CP and INEPT 13 C ssNMR spectra to different signals originating from the mobile and rigid fractions of the biofilm, and qualitative determined dynamical changes by comparing CP buildup behaviors. Protein and polysaccharide signals were differentiated and identified by utilizing FapC signals as a template, a biofilm forming functional amyloid from Pseudomonas . We also attempted to identify biofilm polysaccharide species by using 1 H/ 13 C chemical shifts obtained from the 2D spectrum. This study marks the first demonstration of high-resolution 2D ssNMR spectroscopy for characterizing native bacterial biofilms and expands the scope of ssNMR in studying biofilms. Our experimental pipeline can be readily applied to other in vitro biofilm model systems and natural biofilms and holds the promise of making a substantial impact on biofilm research, fostering new ideas and breakthroughs to aid in the development of strategic approaches to combat infections caused by biofilm-forming bacteria.
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6
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Werby SH, Brčić J, Chosy MB, Sun J, Rendell JT, Neville LF, Wender PA, Cegelski L. Detection of intact vancomycin-arginine as the active antibacterial conjugate in E. coli by whole-cell solid-state NMR. RSC Med Chem 2023; 14:1192-1198. [PMID: 37360389 PMCID: PMC10285746 DOI: 10.1039/d3md00173c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 05/13/2023] [Indexed: 06/28/2023] Open
Abstract
The introduction of new and improved antibacterial agents based on facile synthetic modifications of existing antibiotics represents a promising strategy to deliver urgently needed antibacterial candidates to treat multi-drug resistant bacterial infections. Using this strategy, vancomycin was transformed into a highly active agent against antibiotic-resistant Gram-negative organisms in vitro and in vivo through the addition of a single arginine to yield vancomycin-arginine (V-R). Here, we report detection of the accumulation of V-R in E. coli by whole-cell solid-state NMR using 15N-labeled V-R. 15N CPMAS NMR revealed that the conjugate remained fully amidated without loss of arginine, demonstrating that intact V-R represents the active antibacterial agent. Furthermore, C{N}REDOR NMR in whole cells with all carbons at natural abundance 13C levels exhibited the sensitivity and selectivity to detect the directly bonded 13C-15N pairs of V-R within E. coli cells. Thus, we also present an effective methodology to directly detect and evaluate active drug agents and their accumulation within bacteria without the need for potentially perturbative cell lysis and analysis protocols.
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Affiliation(s)
- Sabrina H Werby
- Department of Chemistry, Stanford University Stanford CA 94305 USA
| | - Jasna Brčić
- Department of Chemistry, Stanford University Stanford CA 94305 USA
| | - Madeline B Chosy
- Department of Chemistry, Stanford University Stanford CA 94305 USA
| | - Jiuzhi Sun
- Department of Chemistry, Stanford University Stanford CA 94305 USA
| | | | | | - Paul A Wender
- Department of Chemistry, Stanford University Stanford CA 94305 USA
- Department of Chemical and Systems Biology, Stanford University Stanford CA 94305 USA
| | - Lynette Cegelski
- Department of Chemistry, Stanford University Stanford CA 94305 USA
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7
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Solid-state NMR molecular snapshots of Aspergillus fumigatus cell wall architecture during a conidial morphotype transition. Proc Natl Acad Sci U S A 2023; 120:e2212003120. [PMID: 36719915 PMCID: PMC9963690 DOI: 10.1073/pnas.2212003120] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
While establishing an invasive infection, the dormant conidia of Aspergillus fumigatus transit through swollen and germinating stages, to form hyphae. During this morphotype transition, the conidial cell wall undergoes dynamic remodeling, which poses challenges to the host immune system and antifungal drugs. However, such cell wall reorganization during conidial germination has not been studied so far. Here, we explored the molecular rearrangement of Aspergillus fumigatus cell wall polysaccharides during different stages of germination. We took advantage of magic-angle spinning NMR to investigate the cell wall polysaccharides, without employing any destructive method for sample preparation. The breaking of dormancy was associated with a significant change in the molar ratio between the major polysaccharides β-1,3-glucan and α-1,3-glucan, while chitin remained equally abundant. The use of various polarization transfers allowed the detection of rigid and mobile polysaccharides; the appearance of mobile galactosaminogalactan was a molecular hallmark of germinating conidia. We also report for the first time highly abundant triglyceride lipids in the mobile matrix of conidial cell walls. Water to polysaccharides polarization transfers revealed an increased surface exposure of glucans during germination, while chitin remained embedded deeper in the cell wall, suggesting a molecular compensation mechanism to keep the cell wall rigidity. We complement the NMR analysis with confocal and atomic force microscopies to explore the role of melanin and RodA hydrophobin on the dormant conidial surface. Exemplified here using Aspergillus fumigatus as a model, our approach provides a powerful tool to decipher the molecular remodeling of fungal cell walls during their morphotype switching.
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8
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Theillet FX, Luchinat E. In-cell NMR: Why and how? PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 132-133:1-112. [PMID: 36496255 DOI: 10.1016/j.pnmrs.2022.04.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/19/2022] [Accepted: 04/27/2022] [Indexed: 06/17/2023]
Abstract
NMR spectroscopy has been applied to cells and tissues analysis since its beginnings, as early as 1950. We have attempted to gather here in a didactic fashion the broad diversity of data and ideas that emerged from NMR investigations on living cells. Covering a large proportion of the periodic table, NMR spectroscopy permits scrutiny of a great variety of atomic nuclei in all living organisms non-invasively. It has thus provided quantitative information on cellular atoms and their chemical environment, dynamics, or interactions. We will show that NMR studies have generated valuable knowledge on a vast array of cellular molecules and events, from water, salts, metabolites, cell walls, proteins, nucleic acids, drugs and drug targets, to pH, redox equilibria and chemical reactions. The characterization of such a multitude of objects at the atomic scale has thus shaped our mental representation of cellular life at multiple levels, together with major techniques like mass-spectrometry or microscopies. NMR studies on cells has accompanied the developments of MRI and metabolomics, and various subfields have flourished, coined with appealing names: fluxomics, foodomics, MRI and MRS (i.e. imaging and localized spectroscopy of living tissues, respectively), whole-cell NMR, on-cell ligand-based NMR, systems NMR, cellular structural biology, in-cell NMR… All these have not grown separately, but rather by reinforcing each other like a braided trunk. Hence, we try here to provide an analytical account of a large ensemble of intricately linked approaches, whose integration has been and will be key to their success. We present extensive overviews, firstly on the various types of information provided by NMR in a cellular environment (the "why", oriented towards a broad readership), and secondly on the employed NMR techniques and setups (the "how", where we discuss the past, current and future methods). Each subsection is constructed as a historical anthology, showing how the intrinsic properties of NMR spectroscopy and its developments structured the accessible knowledge on cellular phenomena. Using this systematic approach, we sought i) to make this review accessible to the broadest audience and ii) to highlight some early techniques that may find renewed interest. Finally, we present a brief discussion on what may be potential and desirable developments in the context of integrative studies in biology.
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Affiliation(s)
- Francois-Xavier Theillet
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France.
| | - Enrico Luchinat
- Dipartimento di Scienze e Tecnologie Agro-Alimentari, Alma Mater Studiorum - Università di Bologna, Piazza Goidanich 60, 47521 Cesena, Italy; CERM - Magnetic Resonance Center, and Neurofarba Department, Università degli Studi di Firenze, 50019 Sesto Fiorentino, Italy
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9
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Kumari S, Booth V. Antimicrobial Peptide Mechanisms Studied by Whole-Cell Deuterium NMR. Int J Mol Sci 2022; 23:ijms23052740. [PMID: 35269882 PMCID: PMC8910884 DOI: 10.3390/ijms23052740] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/24/2022] [Accepted: 02/26/2022] [Indexed: 12/29/2022] Open
Abstract
Much of the work probing antimicrobial peptide (AMP) mechanisms has focussed on how these molecules permeabilize lipid bilayers. However, AMPs must also traverse a variety of non-lipid cell envelope components before they reach the lipid bilayer. Additionally, there is a growing list of AMPs with non-lipid targets inside the cell. It is thus useful to extend the biophysical methods that have been traditionally applied to study AMP mechanisms in liposomes to the full bacteria, where the lipids are present along with the full complexity of the rest of the bacterium. This review focusses on what can be learned about AMP mechanisms from solid-state NMR of AMP-treated intact bacteria. It also touches on flow cytometry as a complementary method for measuring permeabilization of bacterial lipid membranes in whole bacteria.
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Affiliation(s)
- Sarika Kumari
- Department of Biochemistry, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada;
| | - Valerie Booth
- Department of Biochemistry, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada;
- Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
- Correspondence: ; Tel.: +1-709-864-4523
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10
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Ghassemi N, Poulhazan A, Deligey F, Mentink-Vigier F, Marcotte I, Wang T. Solid-State NMR Investigations of Extracellular Matrixes and Cell Walls of Algae, Bacteria, Fungi, and Plants. Chem Rev 2021; 122:10036-10086. [PMID: 34878762 DOI: 10.1021/acs.chemrev.1c00669] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Extracellular matrixes (ECMs), such as the cell walls and biofilms, are important for supporting cell integrity and function and regulating intercellular communication. These biomaterials are also of significant interest to the production of biofuels and the development of antimicrobial treatment. Solid-state nuclear magnetic resonance (ssNMR) and magic-angle spinning-dynamic nuclear polarization (MAS-DNP) are uniquely powerful for understanding the conformational structure, dynamical characteristics, and supramolecular assemblies of carbohydrates and other biomolecules in ECMs. This review highlights the recent high-resolution investigations of intact ECMs and native cells in many organisms spanning across plants, bacteria, fungi, and algae. We spotlight the structural principles identified in ECMs, discuss the current technical limitation and underexplored biochemical topics, and point out the promising opportunities enabled by the recent advances of the rapidly evolving ssNMR technology.
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Affiliation(s)
- Nader Ghassemi
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Alexandre Poulhazan
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States.,Department of Chemistry, Université du Québec à Montréal, Montreal H2X 2J6, Canada
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | | | - Isabelle Marcotte
- Department of Chemistry, Université du Québec à Montréal, Montreal H2X 2J6, Canada
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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11
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Zhao L, Wei J, Pan X, Jie Y, Zhu B, Zhao H, Zhang B. Critical analysis of peptidoglycan structure of Lactobacillus acidophilus for phthalate removal. CHEMOSPHERE 2021; 282:130982. [PMID: 34111639 DOI: 10.1016/j.chemosphere.2021.130982] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 03/05/2021] [Accepted: 05/22/2021] [Indexed: 06/12/2023]
Abstract
Our previous studies have shown that lactic acid bacteria (LABs) can bind and remove di-n-butyl phthalate (DBP), diethyl phthalate, and dioctyl phthalate; three ubiquitous environmental phthalate contaminants. In this study, Lactobacillus acidophilus NCFM was chosen to study the DBP binding mechanism. We found that the three-dimensional structure of the bacterial cell wall, including the carbohydrates and proteins, was essential for DBP adsorption. Peptidoglycan was the main binding component in the cell wall (80.71%), and binding sites exposed to DBP were C-N, N-H, O-H, and C-O bonds. Molecular dynamic (MD) studies demonstrated that hydrophobic interaction plays an important role in DBP adsorption, the chemical sites that influenced the binding in the peptidoglycan model were O2, O3>N1, N2, N3>O1, O4, and the form of adsorption force included hydrogen bonding force, electrostatic force, and van der Waals forces. These theoretical data from the MD simulation were consistent with the experimental results in terms of the ability of this bacterium to bind DBP, so the MD simulation proposed a new way to investigate the mechanisms of phthalate binding to LABs.
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Affiliation(s)
- Lili Zhao
- School of Biological Science & Biotechnology, Beijing Forestry University, 100083 Beijing, China; College of Life Sciences, Henan Normal University, 453007 Xinxiang, China
| | - Junyan Wei
- School of Biological Science & Biotechnology, Beijing Forestry University, 100083 Beijing, China
| | - Xin Pan
- College of Life Sciences, Henan Normal University, 453007 Xinxiang, China
| | - Yu Jie
- School of Biological Science & Biotechnology, Beijing Forestry University, 100083 Beijing, China
| | - Baoqing Zhu
- School of Biological Science & Biotechnology, Beijing Forestry University, 100083 Beijing, China
| | - Hongfei Zhao
- School of Biological Science & Biotechnology, Beijing Forestry University, 100083 Beijing, China
| | - Bolin Zhang
- School of Biological Science & Biotechnology, Beijing Forestry University, 100083 Beijing, China.
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12
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Phyo P, Zhao X, Templeton AC, Xu W, Cheung JK, Su Y. Understanding molecular mechanisms of biologics drug delivery and stability from NMR spectroscopy. Adv Drug Deliv Rev 2021; 174:1-29. [PMID: 33609600 DOI: 10.1016/j.addr.2021.02.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/20/2021] [Accepted: 02/07/2021] [Indexed: 02/06/2023]
Abstract
Protein therapeutics carry inherent limitations of membrane impermeability and structural instability, despite their predominant role in the modern pharmaceutical market. Effective formulations are needed to overcome physiological and physicochemical barriers, respectively, for improving bioavailability and stability. Knowledge of membrane affinity, cellular internalization, encapsulation, and release of drug-loaded carrier vehicles uncover the structural basis for designing and optimizing biopharmaceuticals with enhanced delivery efficiency and therapeutic efficacy. Understanding stabilizing and destabilizing interactions between protein drugs and formulation excipients provide fundamental mechanisms for ensuring the stability and quality of biological products. This article reviews the molecular studies of biologics using solution and solid-state NMR spectroscopy on structural attributes pivotal to drug delivery and stability. In-depth investigation of the structure-function relationship of drug delivery systems based on cell-penetrating peptides, lipid nanoparticles and polymeric colloidal, and biophysical and biochemical stability of peptide, protein, monoclonal antibody, and vaccine, as the integrative efforts on drug product design, will be elaborated.
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Affiliation(s)
- Pyae Phyo
- Pharmaceutical Sciences, Merck & Co., Inc., Kenilworth, NJ 07033, United States
| | - Xi Zhao
- Pharmaceutical Sciences, Merck & Co., Inc., Kenilworth, NJ 07033, United States
| | - Allen C Templeton
- Pharmaceutical Sciences, Merck & Co., Inc., Kenilworth, NJ 07033, United States
| | - Wei Xu
- Pharmaceutical Sciences, Merck & Co., Inc., Kenilworth, NJ 07033, United States
| | - Jason K Cheung
- Pharmaceutical Sciences, Merck & Co., Inc., Kenilworth, NJ 07033, United States
| | - Yongchao Su
- Pharmaceutical Sciences, Merck & Co., Inc., Kenilworth, NJ 07033, United States.
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13
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Brown AR, Gordon RA, Hyland SN, Siegrist MS, Grimes CL. Chemical Biology Tools for Examining the Bacterial Cell Wall. Cell Chem Biol 2020; 27:1052-1062. [PMID: 32822617 DOI: 10.1016/j.chembiol.2020.07.024] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/06/2020] [Accepted: 07/29/2020] [Indexed: 01/22/2023]
Abstract
Bacteria surround themselves with cell walls to maintain cell rigidity and protect against environmental insults. Here we review chemical and biochemical techniques employed to study bacterial cell wall biogenesis. Recent advances including the ability to isolate critical intermediates, metabolic approaches for probe incorporation, and isotopic labeling techniques have provided critical insight into the biochemistry of cell walls. Fundamental manuscripts that have used these techniques to discover cell wall-interacting proteins, flippases, and cell wall stoichiometry are discussed in detail. The review highlights that these powerful methods and techniques have exciting potential to identify and characterize new targets for antibiotic development.
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Affiliation(s)
- Ashley R Brown
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Rebecca A Gordon
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003-9298, USA; Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst 01003-9298, USA
| | - Stephen N Hyland
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - M Sloan Siegrist
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003-9298, USA; Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst 01003-9298, USA
| | - Catherine L Grimes
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA; Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA.
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14
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Molecular study of binding of Plasmodium ribosomal protein P2 to erythrocytes. Biochimie 2020; 176:181-191. [PMID: 32717409 DOI: 10.1016/j.biochi.2020.07.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 06/13/2020] [Accepted: 07/09/2020] [Indexed: 11/23/2022]
Abstract
The ribosomal protein P2 of Plasmodium falciparum, (PfP2), performs certain unique extra-ribosomal functions. During the few hours of cell-division, PfP2 protein moves to the external surface of the infected erythrocytes (IE) as an SDS-resistant oligomer, and at that stage treatment with specific anti- PfP2 antibodies results in an arrest of the parasite cell-division. Amongst the oligomeric forms of PfP2, mainly the homo-tetramer is peripherally anchored on the external surface of the IE. To study the anchoring of PfP2 tetramer on IE-surface, we have explored the binding properties of PfP2 protein. Using NMR and erythrocyte pull-down studies, here we report that the homo-tetrameric PfP2 protein interacted specifically with erythrocytes and not leukocytes. The hydrophobic N-terminal 72 amino acid region is the major interacting domain. The binding of P2 to RBCs was neuraminidase resistant, but trypsin sensitive. The RBC binding was exclusive to the Plasmodium PfP2 protein as even the homologous protein of the closely related Apicomplexan parasite Toxoplasma gondii TgP2 protein did not interact with erythrocytes. Pull down assays, immunoprecipitation and mass spectrometry data showed that erythrocytic Band 3 protein is a possible interactor of Plasmodium PfP2 protein on the erythrocyte surface.
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15
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Chakraborty A, Deligey F, Quach J, Mentink-Vigier F, Wang P, Wang T. Biomolecular complex viewed by dynamic nuclear polarization solid-state NMR spectroscopy. Biochem Soc Trans 2020; 48:1089-1099. [PMID: 32379300 PMCID: PMC7565284 DOI: 10.1042/bst20191084] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/17/2020] [Accepted: 04/20/2020] [Indexed: 01/07/2023]
Abstract
Solid-state nuclear magnetic resonance (ssNMR) is an indispensable tool for elucidating the structure and dynamics of insoluble and non-crystalline biomolecules. The recent advances in the sensitivity-enhancing technique magic-angle spinning dynamic nuclear polarization (MAS-DNP) have substantially expanded the territory of ssNMR investigations and enabled the detection of polymer interfaces in a cellular environment. This article highlights the emerging MAS-DNP approaches and their applications to the analysis of biomolecular composites and intact cells to determine the folding pathway and ligand binding of proteins, the structural polymorphism of low-populated biopolymers, as well as the physical interactions between carbohydrates, proteins, and lignin. These structural features provide an atomic-level understanding of many cellular processes, promoting the development of better biomaterials and inhibitors. It is anticipated that the capabilities of MAS-DNP in biomolecular and biomaterial research will be further enlarged by the rapid development of instrumentation and methodology.
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Affiliation(s)
- Arnab Chakraborty
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Jenny Quach
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | | | - Ping Wang
- Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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16
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Zhao W, Fernando LD, Kirui A, Deligey F, Wang T. Solid-state NMR of plant and fungal cell walls: A critical review. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2020; 107:101660. [PMID: 32251983 DOI: 10.1016/j.ssnmr.2020.101660] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 03/17/2020] [Indexed: 05/22/2023]
Abstract
The cell walls of plants and microbes are a central source for bio-renewable energy and the major targets of antibiotics and antifungal agents. It is highly challenging to determine the molecular structure of complex carbohydrates, protein and lignin, and their supramolecular assembly in intact cell walls. This article selectively highlights the recent breakthroughs that employ 13C/15N solid-state NMR techniques to elucidate the architecture of fungal cell walls in Aspergillus fumigatus and the primary and secondary cell walls in a large variety of plant species such as Arabidopsis, Brachypodium, maize, and spruce. Built upon these pioneering studies, we further summarize the underexplored aspects of fungal and plant cell walls. The new research opportunities introduced by innovative methods, such as the detection of proton and quadrupolar nuclei on ultrahigh-field magnets and under fast magic-angle spinning, paramagnetic probes, natural-abundance DNP, and software development, are also critically discussed.
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Affiliation(s)
- Wancheng Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Liyanage D Fernando
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Alex Kirui
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA.
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17
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Caudill ER, Hernandez RT, Johnson KP, O'Rourke JT, Zhu L, Haynes CL, Feng ZV, Pedersen JA. Wall teichoic acids govern cationic gold nanoparticle interaction with Gram-positive bacterial cell walls. Chem Sci 2020; 11:4106-4118. [PMID: 34122876 PMCID: PMC8152635 DOI: 10.1039/c9sc05436g] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 03/20/2020] [Indexed: 11/21/2022] Open
Abstract
Molecular-level understanding of nanomaterial interactions with bacterial cell surfaces can facilitate design of antimicrobial and antifouling surfaces and inform assessment of potential consequences of nanomaterial release into the environment. Here, we investigate the interaction of cationic nanoparticles with the main surface components of Gram-positive bacteria: peptidoglycan and teichoic acids. We employed intact cells and isolated cell walls from wild type Bacillus subtilis and two mutant strains differing in wall teichoic acid composition to investigate interaction with gold nanoparticles functionalized with cationic, branched polyethylenimine. We quantified nanoparticle association with intact cells by flow cytometry and determined sites of interaction by solid-state 31P- and 13C-NMR spectroscopy. We find that wall teichoic acid structure and composition were important determinants for the extent of interaction with cationic gold nanoparticles. The nanoparticles interacted more with wall teichoic acids from the wild type and mutant lacking glucose in its wall teichoic acids than those from the mutant having wall teichoic acids lacking alanine and exhibiting more restricted molecular motion. Our experimental evidence supports the interpretation that electrostatic forces contributed to nanoparticle-cell interactions and that the accessibility of negatively charged moieties in teichoic acid chains influences the degree of interaction. The approaches employed in this study can be applied to engineered nanomaterials differing in core composition, shape, or surface functional groups as well as to other types of bacteria to elucidate the influence of nanoparticle and cell surface properties on interactions with Gram-positive bacteria.
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Affiliation(s)
- Emily R Caudill
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
| | | | - Kyle P Johnson
- Department of Chemistry, University of Minnesota Minneapolis MN 55455 USA
| | - James T O'Rourke
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
| | - Lingchao Zhu
- Department of Chemistry, University of Pennsylvania 231 S 34th St Philadelphia PA 19104 USA
| | - Christy L Haynes
- Department of Chemistry, University of Minnesota Minneapolis MN 55455 USA
| | - Z Vivian Feng
- Chemistry Department, Augsburg University Minneapolis MN 55454 USA
| | - Joel A Pedersen
- Department of Chemistry, University of Wisconsin-Madison 1101 University Avenue Madison WI 53706 USA
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison 660 North Part Street Madison WI 53706 USA
- Department of Soil Science, University of Wisconsin-Madison 1525 Observatory Drive Madison WI 53706 USA
- Department of Civil & Environmental Engineering, University of Wisconsin-Madison 1415 Engineering Drive Madison WI 53706 USA
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18
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Rabiah NI, Romaniuk JAH, Fuller GG, Scales CW, Cegelski L. Carbon compositional analysis of hydrogel contact lenses by solid-state NMR spectroscopy. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2019; 102:47-52. [PMID: 31376631 DOI: 10.1016/j.ssnmr.2019.07.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/13/2019] [Accepted: 07/17/2019] [Indexed: 06/10/2023]
Abstract
Contact lenses are worn by over 140 million people each year and tremendous research and development efforts contribute to the identification and selection of hydrogel components and production protocols to yield lenses optimized for chemical and physiological properties, eye health and comfort. The final molecular composition and extent of incorporation of different components in contact lenses is routinely estimated after lens production through the analysis of the soluble components that were not included in the lens, i.e. remaining starting materials. Examination of composition in the actual intact materials is always valued and can reveal details that are missed by only examining the non-incorporated components, for example identifying chemical changes to components in lenses during the production process. Solid-state nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for the direct compositional analysis of insoluble and heterogeneous materials and is also uniquely suited to determining parameters of architecture in contact lenses. We utilized 13C cross-polarization magic angle spinning (CPMAS) NMR to examine and compare the carbon composition of soft contact lenses. 13C NMR spectra of individual polymer components enabled the determination of the approximate molecular carbon contributions of major lens components. Comparisons of the conventional etafilcon A hydrogel (1 Day Acuvue MOIST) lenses and silicone hydrogel lenses (Acuvue Oasys, Dailies Total 1, Clariti 1 Day, Biofinity, and Pure Vision) revealed major spectral differences, with considerable variation even among different silicone hydrogel lenses. The solid-state NMR approach provides a direct spectral reporting of carbon types in the hydrogel lens itself. This approach represents a valuable complementary analysis to benefit contact lens research and development and could be extended to isotopically labeled hydrogel lenses to map proximities and architecture between hydrogel components.
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Affiliation(s)
- Noelle I Rabiah
- Department of Chemical Engineering, Stanford University, Stanford, CA, 94305, United States
| | - Joseph A H Romaniuk
- Department of Chemistry, Stanford University, Stanford, CA, 94305, United States
| | - Gerald G Fuller
- Department of Chemical Engineering, Stanford University, Stanford, CA, 94305, United States
| | - Charles W Scales
- Johnson & Johnson Vision Care, Inc. Jacksonville, FL, 32256, United States
| | - Lynette Cegelski
- Department of Chemistry, Stanford University, Stanford, CA, 94305, United States.
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19
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Antonoplis A, Zang X, Huttner MA, Chong KKL, Lee YB, Co JY, Amieva MR, Kline KA, Wender PA, Cegelski L. A Dual-Function Antibiotic-Transporter Conjugate Exhibits Superior Activity in Sterilizing MRSA Biofilms and Killing Persister Cells. J Am Chem Soc 2018; 140:16140-16151. [PMID: 30388366 PMCID: PMC6430714 DOI: 10.1021/jacs.8b08711] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
New strategies are urgently needed to target MRSA, a major global health problem and the leading cause of mortality from antibiotic-resistant infections in many countries. Here, we report a general approach to this problem exemplified by the design and synthesis of a vancomycin-d-octaarginine conjugate (V-r8) and investigation of its efficacy in addressing antibiotic-insensitive bacterial populations. V-r8 eradicated MRSA biofilm and persister cells in vitro, outperforming vancomycin by orders of magnitude. It also eliminated 97% of biofilm-associated MRSA in a murine wound infection model and displayed no acute dermal toxicity. This new dual-function conjugate displays enhanced cellular accumulation and membrane perturbation as compared to vancomycin. Based on its rapid and potent activity against biofilm and persister cells, V-r8 is a promising agent against clinical MRSA infections.
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Affiliation(s)
- Alexandra Antonoplis
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Xiaoyu Zang
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Melanie A. Huttner
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Kelvin K. L. Chong
- Singapore Centre for Environmental Life Science Engineering (SCELSE), School of Biological Sciences, Nanyang Technological University, Singapore 637551
- Nanyang Technological University Institute for Health Technologies, Interdisciplinary Graduate School, Nanyang Technological University, Singapore 637553
| | - Yu B. Lee
- Singapore Centre for Environmental Life Science Engineering (SCELSE), School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Julia Y. Co
- Department of Pediatrics, Division of Infectious Diseases, Stanford University, Stanford, California 94305, United States
| | - Manuel R. Amieva
- Department of Pediatrics, Division of Infectious Diseases, Stanford University, Stanford, California 94305, United States
- Department of Microbiology & Immunology, Stanford University, Stanford, California 94305, United States
| | - Kimberly A. Kline
- Singapore Centre for Environmental Life Science Engineering (SCELSE), School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Paul A. Wender
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
- Department of Chemical and Systems Biology, Stanford University, Stanford, California 94305, United States
| | - Lynette Cegelski
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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20
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Romaniuk JAH, Cegelski L. Peptidoglycan and Teichoic Acid Levels and Alterations in Staphylococcus aureus by Cell-Wall and Whole-Cell Nuclear Magnetic Resonance. Biochemistry 2018; 57:3966-3975. [PMID: 29806458 PMCID: PMC6309457 DOI: 10.1021/acs.biochem.8b00495] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Gram-positive bacteria surround themselves with a multilayered macromolecular cell wall that is essential to cell survival and serves as a major target for antibiotics. The cell wall of Staphylococcus aureus is composed of two major structural components, peptidoglycan (PG) and wall teichoic acid (WTA), together creating a heterogeneous and insoluble matrix that poses a challenge to quantitative compositional analysis. Here, we present 13C cross polarization magic angle spinning solid-state nuclear magnetic resonance (NMR) spectra of intact cell walls, purified PG, and purified WTA. The spectra reveal the clear molecular differences in the two polymers and enable quantification of PG and WTA in isolated cell walls, an attractive alternative to estimating teichoic acid content from a phosphate analysis of completely pyrolyzed cell walls. Furthermore, we discovered that unique PG and WTA spectral signatures could be identified in whole-cell NMR spectra and used to compare PG and WTA levels among intact bacterial cell samples. The distinguishing whole-cell 13C NMR contributions associated with PG include the GlcNAc-MurNAc sugar carbons and glycyl α-carbons. WTA contributes carbons from the phosphoribitol backbone. Distinguishing 15N spectral signatures include glycyl amide nitrogens in PG and the esterified d-alanyl amine nitrogens in WTA. 13C NMR analysis was performed with samples at natural abundance and included 10 whole-cell sample comparisons. Changes consistent with altered PG and WTA content were detected in whole-cell spectra of bacteria harvested at different growth times and in cells treated with tunicamycin. This use of whole-cell NMR provides quantitative parameters of composition in the context of whole-cell activity.
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Affiliation(s)
| | - Lynette Cegelski
- Stanford University, Department of Chemistry, 380 Roth Way, Stanford CA 94305
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21
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Kobayashi-Kirschvink KJ, Nakaoka H, Oda A, Kamei KIF, Nosho K, Fukushima H, Kanesaki Y, Yajima S, Masaki H, Ohta K, Wakamoto Y. Linear Regression Links Transcriptomic Data and Cellular Raman Spectra. Cell Syst 2018; 7:104-117.e4. [PMID: 29936183 DOI: 10.1016/j.cels.2018.05.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 04/10/2018] [Accepted: 05/21/2018] [Indexed: 10/28/2022]
Abstract
Raman microscopy is an imaging technique that has been applied to assess molecular compositions of living cells to characterize cell types and states. However, owing to the diverse molecular species in cells and challenges of assigning peaks to specific molecules, it has not been clear how to interpret cellular Raman spectra. Here, we provide firm evidence that cellular Raman spectra and transcriptomic profiles of Schizosaccharomyces pombe and Escherichia coli can be computationally connected and thus interpreted. We find that the dimensions of high-dimensional Raman spectra and transcriptomes measured by RNA sequencing can be reduced and connected linearly through a shared low-dimensional subspace. Accordingly, we were able to predict global gene expression profiles by applying the calculated transformation matrix to Raman spectra, and vice versa. Highly expressed non-coding RNAs contributed to the Raman-transcriptome linear correspondence more significantly than mRNAs in S. pombe. This demonstration of correspondence between cellular Raman spectra and transcriptomes is a promising step toward establishing spectroscopic live-cell omics studies.
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Affiliation(s)
- Koseki J Kobayashi-Kirschvink
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan.
| | - Hidenori Nakaoka
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan; Research Center for Complex Systems Biology, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan
| | - Arisa Oda
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan
| | - Ken-Ichiro F Kamei
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan
| | - Kazuki Nosho
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hiroko Fukushima
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Yu Kanesaki
- NODAI Genome Research Center, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan; Research Institute of Green Science and Technology, Shizuoka University, Suruga-ku, Shizuoka 422-8529, Japan
| | - Shunsuke Yajima
- NODAI Genome Research Center, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan; Department of Bioscience, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan
| | - Haruhiko Masaki
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Kunihiro Ohta
- Research Center for Complex Systems Biology, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan; Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan; Universal Biology Institute, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yuichi Wakamoto
- Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan; Research Center for Complex Systems Biology, The University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan; Universal Biology Institute, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
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22
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Spectral comparisons of mammalian cells and intact organelles by solid-state NMR. J Struct Biol 2018; 206:49-54. [PMID: 29859329 DOI: 10.1016/j.jsb.2018.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 03/15/2018] [Accepted: 05/25/2018] [Indexed: 01/18/2023]
Abstract
Whole-cell protein profiling, spatial localization, and quantification of activities such as gene transcription and protein translation are possible with modern biochemical and biophysical techniques. Yet, addressing questions of overall compositional changes within a cell - capturing the relative amounts of protein and ribosomal RNA levels and lipid content simultaneously - would require extractions and purifications with caveats due to isolation yields and detection methods. A holistic view of cellular composition would aid in the study of cellular composition and function. Here, solid state NMR is used to identify 13C NMR signatures for cellular organelles in HeLa cells without the use of any isotopic labeling. Comparisons are made with carbon spectra of subcellular assemblies including DNA, lipids, ribosomes, nuclei and mitochondria. Whole-cell comparisons are made with different mammalian cells lines, with red blood cells that lack nuclei and organelles, and with Gram-negative and Gram-positive bacteria. Furthermore, treatment of mammalian cells with cycloheximide, a commonly used protein synthesis inhibitor, revealed unanticipated changes consistent with a significant increase in protein glycosylation, obvious at the whole cell level. Thus, we demonstrate that solid-state NMR serves as a unique analytical tool to catalog and compare the ratios of distinct carbon types in cells and serves as a discovery tool to reveal the workings of inhibitors such as cycloheximide on whole-cell biochemistry.
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23
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New insights into the influence of monofluorination on dimyristoylphosphatidylcholine membrane properties: A solid-state NMR study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:654-663. [DOI: 10.1016/j.bbamem.2017.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 11/29/2017] [Accepted: 12/04/2017] [Indexed: 10/18/2022]
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24
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Nygaard R, Romaniuk JAH, Rice DM, Cegelski L. Whole Ribosome NMR: Dipolar Couplings and Contributions to Whole Cells. J Phys Chem B 2017; 121:9331-9335. [PMID: 28901760 DOI: 10.1021/acs.jpcb.7b06736] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Solid-state NMR is a powerful tool for quantifying chemical composition and structure in complex assemblies and even whole cells. We employed N{P} REDOR NMR to obtain atomic-level distance propensities in intact 15N-labeled E. coli ribosomes. The experimental REDOR dephasing of shift-resolved lysyl amine nitrogens by phosphorus was comparable to that expected from a calculation of N-P distances involving the lysines included in the crystal structure coordinates. Among the nitrogen contributions to the REDOR spectra, the strongest dephasing emerged from the dipolar couplings to phosphorus involving nitrogen peaks ascribed primarily to rRNA, and the weakest dephasing arose from protein amide nitrogens. This approach is applicable to any macromolecular system and provides quantitative comparisons of distance proximities between shift-resolved nuclei of one type and heteronuclear dephasing spins. Enhanced molecular specificity could be achieved through the use of spectroscopic filters or specific labeling. Furthermore, ribosome 13C and 15N CPMAS spectra were compared with those of whole cells from which the ribosomes were isolated. Whole-cell signatures of ribosomes were identified and should be of value in comparing overall cellular ribosome content in whole-cell samples.
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Affiliation(s)
- Rie Nygaard
- Department of Chemistry, Stanford University , 380 Roth Way, Stanford California 94305, United States
| | - Joseph A H Romaniuk
- Department of Chemistry, Stanford University , 380 Roth Way, Stanford California 94305, United States
| | - David M Rice
- Department of Chemistry, Stanford University , 380 Roth Way, Stanford California 94305, United States
| | - Lynette Cegelski
- Department of Chemistry, Stanford University , 380 Roth Way, Stanford California 94305, United States
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25
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Booth V, Warschawski DE, Santisteban NP, Laadhari M, Marcotte I. Recent progress on the application of 2H solid-state NMR to probe the interaction of antimicrobial peptides with intact bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:1500-1511. [PMID: 28844739 DOI: 10.1016/j.bbapap.2017.07.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Revised: 07/13/2017] [Accepted: 07/25/2017] [Indexed: 10/19/2022]
Abstract
Discoveries relating to innate immunity and antimicrobial peptides (AMPs) granted Bruce Beutler and Jules Hoffmann a Nobel prize in medicine in 2011, and opened up new avenues for the development of therapies against infections, and even cancers. The mechanisms by which AMPs interact with, and ultimately disrupt, bacterial cell membranes is still, to a large extent, incompletely understood. Up until recently, this mechanism was studied using model lipid membranes that failed to reproduce the complexity of molecular interactions present in real cells comprising lipids but also membrane proteins, a cell wall containing peptidoglycan or lipopolysaccharides, and other molecules. In this review, we focus on recent attempts to study, at the molecular level, the interaction between cationic AMPs and intact bacteria, by 2H solid-state NMR. Specifically-labeled lipids allow us to focus on the interaction of AMPs with the heart of the bacterial membrane, and measure the lipid order and its variation upon interaction with various peptides. We will review the important parameters to consider in such a study, and summarize the results obtained in the past 5years on various peptides, in particular aurein 1.2, caerin 1.1, MSI-78 and CA(1-8)M(1-10). This article is part of a Special Issue entitled: Biophysics in Canada, edited by Lewis Kay, John Baenziger, Albert Berghuis and Peter Tieleman.
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Affiliation(s)
- Valerie Booth
- Department of Biochemistry, Memorial University of Newfoundland, St. John's, NL A1B 3X9, Canada; Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John's, NL A1B 3X7, Canada
| | - Dror E Warschawski
- UMR 7099, CNRS - Université Paris Diderot, IBPC, 13 rue Pierre et Marie Curie, F-75005 Paris, France; Department of Chemistry, Université du Québec à Montréal, P.O. Box 8888, Downtown Station, Montréal H3C 3P8, Canada
| | - Nury P Santisteban
- Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John's, NL A1B 3X7, Canada
| | - Marwa Laadhari
- Department of Chemistry, Université du Québec à Montréal, P.O. Box 8888, Downtown Station, Montréal H3C 3P8, Canada
| | - Isabelle Marcotte
- Department of Chemistry, Université du Québec à Montréal, P.O. Box 8888, Downtown Station, Montréal H3C 3P8, Canada.
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26
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Li C, Zhao J, Cheng K, Ge Y, Wu Q, Ye Y, Xu G, Zhang Z, Zheng W, Zhang X, Zhou X, Pielak G, Liu M. Magnetic Resonance Spectroscopy as a Tool for Assessing Macromolecular Structure and Function in Living Cells. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2017; 10:157-182. [PMID: 28301750 DOI: 10.1146/annurev-anchem-061516-045237] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Investigating the structure, modification, interaction, and function of biomolecules in their native cellular environment leads to physiologically relevant knowledge about their mechanisms, which will benefit drug discovery and design. In recent years, nuclear and electron magnetic resonance (NMR) spectroscopy has emerged as a useful tool for elucidating the structure and function of biomacromolecules, including proteins, nucleic acids, and carbohydrates in living cells at atomic resolution. In this review, we summarize the progress and future of in-cell NMR as it is applied to proteins, nucleic acids, and carbohydrates.
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Affiliation(s)
- Conggang Li
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Jiajing Zhao
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Kai Cheng
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Yuwei Ge
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Qiong Wu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Yansheng Ye
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Guohua Xu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Zeting Zhang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Wenwen Zheng
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Xu Zhang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Xin Zhou
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
| | - Gary Pielak
- Department of Chemistry, Department of Biochemistry and Biophysics, and Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Maili Liu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; ,
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27
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Affiliation(s)
- Benjamin J. Wylie
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, USA
| | - Hoa Q. Do
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, USA
| | - Collin G. Borcik
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, USA
| | - Emily P. Hardy
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, USA
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In-Cell Solid-State NMR: An Emerging Technique for the Study of Biological Membranes. Biophys J 2016; 109:2461-2466. [PMID: 26682804 DOI: 10.1016/j.bpj.2015.10.041] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 10/20/2015] [Accepted: 10/30/2015] [Indexed: 11/22/2022] Open
Abstract
Biological molecular processes are often studied in model systems, which simplifies their inherent complexity but may cause investigators to lose sight of the effects of the molecular environment. Information obtained in this way must therefore be validated by experiments in the cell. NMR has been used to study biological cells since the early days of its development. The first NMR structural studies of a protein inside a cell (by solution-state NMR) and of a membrane protein (by solid-state NMR) were published in 2001 and 2011, respectively. More recently, dynamic nuclear polarization, which has been used to enhance the signal in solid-state NMR, has also been applied to the study of frozen cells. Much progress has been made in the past 5 years, and in this review we take stock of this new technique, which is particularly appropriate for the study of biological membranes.
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Abstract
Biofilm infections are exceptionally recalcitrant to antimicrobial treatment or clearance by host immune responses. Within biofilms, microbes form adherent multicellular communities that are embedded in an extracellular matrix. Many prescribed antifungal drugs are not effective against biofilm infections owing to several protective factors including poor diffusion of drugs through biofilms as well as specific drug-matrix interactions. Despite the key roles that biofilms play in infections, there is little quantitative information about their composition and structural complexity because of the analytical challenge of studying these dense networks using traditional techniques. Within this review, recent work to elucidate fungal biofilm composition is discussed, with particular attention given to the challenges of annotation and quantification of matrix composition.
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30
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Romaniuk JAH, Cegelski L. Bacterial cell wall composition and the influence of antibiotics by cell-wall and whole-cell NMR. Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2015.0024. [PMID: 26370936 DOI: 10.1098/rstb.2015.0024] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The ability to characterize bacterial cell-wall composition and structure is crucial to understanding the function of the bacterial cell wall, determining drug modes of action and developing new-generation therapeutics. Solid-state NMR has emerged as a powerful tool to quantify chemical composition and to map cell-wall architecture in bacteria and plants, even in the context of unperturbed intact whole cells. In this review, we discuss solid-state NMR approaches to define peptidoglycan composition and to characterize the modes of action of old and new antibiotics, focusing on examples in Staphylococcus aureus. We provide perspectives regarding the selected NMR strategies as we describe the exciting and still-developing cell-wall and whole-cell NMR toolkit. We also discuss specific discoveries regarding the modes of action of vancomycin analogues, including oritavancin, and briefly address the reconsideration of the killing action of β-lactam antibiotics. In such chemical genetics approaches, there is still much to be learned from perturbations enacted by cell-wall assembly inhibitors, and solid-state NMR approaches are poised to address questions of cell-wall composition and assembly in S. aureus and other organisms.
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Affiliation(s)
- Joseph A H Romaniuk
- Department of Chemistry, Stanford University, 380 Roth Way, Stanford, CA 94305, USA
| | - Lynette Cegelski
- Department of Chemistry, Stanford University, 380 Roth Way, Stanford, CA 94305, USA
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31
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Tang W, Bhatt A, Smith AN, Crowley PJ, Brady LJ, Long JR. Specific binding of a naturally occurring amyloidogenic fragment of Streptococcus mutans adhesin P1 to intact P1 on the cell surface characterized by solid state NMR spectroscopy. JOURNAL OF BIOMOLECULAR NMR 2016; 64:153-64. [PMID: 26837620 PMCID: PMC4756430 DOI: 10.1007/s10858-016-0017-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 01/24/2016] [Indexed: 06/05/2023]
Abstract
The P1 adhesin (aka Antigen I/II or PAc) of the cariogenic bacterium Streptococcus mutans is a cell surface-localized protein involved in sucrose-independent adhesion and colonization of the tooth surface. The immunoreactive and adhesive properties of S. mutans suggest an unusual functional quaternary ultrastructure comprised of intact P1 covalently attached to the cell wall and interacting with non-covalently associated proteolytic fragments thereof, particularly the ~57-kDa C-terminal fragment C123 previously identified as Antigen II. S. mutans is capable of amyloid formation when grown in a biofilm and P1 is among its amyloidogenic proteins. The C123 fragment of P1 readily forms amyloid fibers in vitro suggesting it may play a role in the formation of functional amyloid during biofilm development. Using wild-type and P1-deficient strains of S. mutans, we demonstrate that solid state NMR (ssNMR) spectroscopy can be used to (1) globally characterize cell walls isolated from a Gram-positive bacterium and (2) characterize the specific binding of heterologously expressed, isotopically-enriched C123 to cell wall-anchored P1. Our results lay the groundwork for future high-resolution characterization of the C123/P1 ultrastructure and subsequent steps in biofilm formation via ssNMR spectroscopy, and they support an emerging model of S. mutans colonization whereby quaternary P1-C123 interactions confer adhesive properties important to binding to immobilized human salivary agglutinin.
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Affiliation(s)
- Wenxing Tang
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, USA
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA
| | - Avni Bhatt
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Adam N Smith
- Department of Chemistry, College of Liberal Arts and Sciences, University of Florida, Gainesville, FL, USA
| | - Paula J Crowley
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA
| | - L Jeannine Brady
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA.
| | - Joanna R Long
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, USA.
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32
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Rice DM, Romaniuk JAH, Cegelski L. Frequency-selective REDOR and spin-diffusion relays in uniformly labeled whole cells. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2015; 72:132-9. [PMID: 26493462 PMCID: PMC4674448 DOI: 10.1016/j.ssnmr.2015.10.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 10/07/2015] [Accepted: 10/08/2015] [Indexed: 06/05/2023]
Abstract
Solid-state NMR is a powerful and non-perturbative method to measure and define chemical composition and architecture in bacterial cell walls, even in the context of whole cells. Most NMR studies on whole cells have used selectively labeled samples. Here, we introduce an NMR sequence relay using frequency-selective REDOR (fsREDOR) and spin diffusion elements to probe a unique amine contribution in uniformly (13)C- and (15)N-labeled Staphylococcus aureus whole cells that we attribute to the d-alanine of teichoic acid. In addition to the primary peptidoglycan structural scaffold, cell walls can contain significant amounts of teichoic acid that contribute to cell-wall function. When incorporated into teichoic acid, d-alanine is present as an ester, connected via its carbonyl to a ribitol carbon, and thus has a free amine. Teichoic acid d-Ala is removed during cell-wall isolations and can only be detected in the context of whole cells. The sequence presented here begins with fsREDOR and a chemical shift evolution period for 2D data acquisition, followed by DARR spin diffusion and then an additional fsREDOR period. fsREDOR elements were used for (13)C observation to avoid complications from (13)C-(13)C couplings due to uniform labeling and for (15)N dephasing to achieve selectivity in the nitrogens serving as dephasers. The results show that the selected amine nitrogen of interest is near to teichoic acid ribitol carbons and also the methyl group carbon associated with alanine. In addition, its carbonyl is not significantly dephased by amide nitrogens, consistent with the expected microenvironment around teichoic acid.
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Affiliation(s)
- David M Rice
- Stanford University, Department of Chemistry, 380 Roth Way, Stanford, CA 94305, USA
| | - Joseph A H Romaniuk
- Stanford University, Department of Chemistry, 380 Roth Way, Stanford, CA 94305, USA
| | - Lynette Cegelski
- Stanford University, Department of Chemistry, 380 Roth Way, Stanford, CA 94305, USA.
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33
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Weliky DP. A new understanding of antibiotic action via solid-state NMR of cells with uniform isotopic labeling. Biophys J 2015; 108:1314. [PMID: 25809244 DOI: 10.1016/j.bpj.2015.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 02/12/2015] [Indexed: 10/23/2022] Open
Affiliation(s)
- David P Weliky
- Department of Chemistry, Michigan State University, East Lansing, Michigan.
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