1
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Rivera K, Tanaka KJ, Buechel ER, Origel O, Harrison A, Mason KM, Pinkett HW. Antimicrobial Peptide Recognition Motif of the Substrate Binding Protein SapA from Nontypeable Haemophilus influenzae. Biochemistry 2024; 63:294-311. [PMID: 38189237 PMCID: PMC10851439 DOI: 10.1021/acs.biochem.3c00562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 12/11/2023] [Accepted: 12/13/2023] [Indexed: 01/09/2024]
Abstract
Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen associated with respiratory diseases, including otitis media and exacerbations of chronic obstructive pulmonary disease. NTHi exhibits resistance to killing by host antimicrobial peptides (AMPs) mediated by SapA, the substrate binding protein of the sensitivity to antimicrobial peptides (Sap) transporter. However, the specific mechanisms by which SapA selectively binds various AMPs such as defensins and cathelicidin are unknown. In this study, we report mutational analyses of both defensin AMPs and the SapA binding pocket to define the specificity of AMP recognition. Bactericidal assays revealed that NTHi lacking SapA are more susceptible to human beta defensins and LL-37, while remaining highly resistant to a human alpha defensin. In contrast to homologues, our research underscores the distinct specificity of NTHi SapA, which selectively recognizes and binds to peptides containing the charged-hydrophobic motif PKE and RRY. These findings provide valuable insight into the divergence of SapA among bacterial species and NTHi SapA's ability to selectively interact with specific AMPs to mediate resistance.
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Affiliation(s)
- Kristen
G. Rivera
- Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
| | - Kari J. Tanaka
- Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
| | - Evan R. Buechel
- Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
| | - Octavio Origel
- Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
| | - Alistair Harrison
- The
Center for Microbial Pathogenesis, The Abigail Wexner Research Institute
at Nationwide Children’s Hospital and College of Medicine,
Department of Pediatrics, The Ohio State
University, Columbus, Ohio 43205, United States
| | - Kevin M. Mason
- The
Center for Microbial Pathogenesis, The Abigail Wexner Research Institute
at Nationwide Children’s Hospital and College of Medicine,
Department of Pediatrics, The Ohio State
University, Columbus, Ohio 43205, United States
| | - Heather W. Pinkett
- Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
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2
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Saad A, Bechinger B. Solid-state NMR spectroscopy for structural studies of polypeptides and lipids in extended physiological membranes. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184162. [PMID: 37949788 DOI: 10.1016/j.bbamem.2023.184162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 04/18/2023] [Accepted: 04/26/2023] [Indexed: 11/12/2023]
Abstract
Solid-state NMR is a quickly developing technique that allows one to obtain structural information at atomic resolution in extended lipid bilayers in a rather unique manner. Two approaches have been developed for membrane proteins and peptides namely magic angle sample spinning and the use of uniaxially oriented membrane samples. The state-of-the-art of both approaches will be introduced and the perspectives of solid-state NMR spectroscopy in the context of other structural biology techniques, pressing biomedical questions and membrane biophysics will be discussed.
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Affiliation(s)
- Ahmad Saad
- Université de Strasbourg/CNRS, UMR7177, Institut de Chimie, 4, rue Blaise Pascal, 67070 Strasbourg, France
| | - Burkhard Bechinger
- Université de Strasbourg/CNRS, UMR7177, Institut de Chimie, 4, rue Blaise Pascal, 67070 Strasbourg, France; Institut Universitaire de France, 75005 Paris, France.
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3
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Awang T, Chairatana P, Pongprayoon P. Molecular dynamics simulations of human α-defensin 5 (HD5) crossing gram-negative bacterial membrane. PLoS One 2023; 18:e0294041. [PMID: 37988380 PMCID: PMC10662769 DOI: 10.1371/journal.pone.0294041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 10/24/2023] [Indexed: 11/23/2023] Open
Abstract
Human α-defensin 5 (HD5) is a cationic antimicrobial peptide exhibiting a wide range of antimicrobial activities. It plays an important role in mucosal immunity of the small intestine. HD5 exerts its bactericidal activities through multiple mechanisms, one of which involves HD5 inducing the formation of pores in the bacterial membrane, subsequently allowing the peptide to enter the bacterial cytoplasm. Nevertheless, the precise molecular intricacies underlying its bactericidal mechanisms remain inadequately understood. In this work, the Potential of Mean Force (PMF) was computed to delve into the energetic properties governing the movement of HD5 across the lipopolysaccharide (LPS) membrane, which is a representative model of the gram-negative bacterial membrane. Our findings indicate that the most favorable free energy is attained when HD5 binds to the surface of the LPS membrane. This favorable interaction is primarily driven by the strong interactions between arginine residues in HD5 and the charged head groups of LPS, serving as the predominant forces facilitating the adhesion of HD5 to the membrane. Our analysis reveals that a dimeric form of HD5 alone is sufficient to create a water-filled channel in the membrane; however, achieving the complete lysis of the gram-negative bacterial membrane requires higher-order oligomerization of HD5. Our results suggest that HD5 employs the toroidal pore formation mechanism to disrupt the integrity of the LPS membrane. Furthermore, we identified that the primary energy barrier obstructing HD5 from traversing the membrane is localized within the hydrophobic core of the membrane, which is also observed for other defensins. Additionally, our study demonstrates that a mixture of HD5-LPS leads to a thinning of the membrane. Taken together, this work provides a deeper insight into the molecular intricacies governing the behavior of HD5 as it translocates through the gram-negative bacterial membrane.
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Affiliation(s)
- Tadsanee Awang
- Department of Chemistry, Faculty of Science, Kasetsart University, Bangkok, Thailand
| | - Phoom Chairatana
- Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Prapasiri Pongprayoon
- Department of Chemistry, Faculty of Science, Kasetsart University, Bangkok, Thailand
- Center for Advanced Studies in Nanotechnology for Chemical, Food and Agricultural Industries, KU Institute for Advanced Studies, Kasetsart University, Bangkok, Thailand
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4
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Deniz Tekin E, Calisir M. Investigation of human β-defensins 1, 2 and 3 in human saliva by molecular dynamics. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2022; 45:100. [PMID: 36542178 DOI: 10.1140/epje/s10189-022-00257-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
Human β-defensins present in saliva have a broad spectrum of antimicrobial activities that work against infections in oral cavity. To provide a better understanding of these molecules' properties and functions at the molecular level, we have investigated and compared the important structural properties of human β-defensin-1, -2 and -3 using molecular dynamics simulations. Our results have shown that human β-defensin-3 has a more flexible structure in water than the other two because of its high hydrophilicity, low β-sheet content and high repulsive forces between its charged residues. Moreover, we found that the location of the salt bridges is important in protein's stability in water. Molecular dynamics simulations of human β-defensins 1, 2 and 3 revealed that the hbd-3 is more flexible in water than hbd-1 and hbd-2.
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Affiliation(s)
- E Deniz Tekin
- Faculty of Engineering, University of Turkish Aeronautical Association, 06790, Ankara, Turkey.
| | - Metin Calisir
- Faculty of Dentistry, Adıyaman University, 02000, Adıyaman, Turkey
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5
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Blair JMA, Zeth K, Bavro VN, Sancho-Vaello E. The role of bacterial transport systems in the removal of host antimicrobial peptides in Gram-negative bacteria. FEMS Microbiol Rev 2022; 46:6617596. [PMID: 35749576 PMCID: PMC9629497 DOI: 10.1093/femsre/fuac032] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 05/23/2022] [Accepted: 06/22/2022] [Indexed: 01/09/2023] Open
Abstract
Antibiotic resistance is a global issue that threatens our progress in healthcare and life expectancy. In recent years, antimicrobial peptides (AMPs) have been considered as promising alternatives to the classic antibiotics. AMPs are potentially superior due to their lower rate of resistance development, since they primarily target the bacterial membrane ('Achilles' heel' of the bacteria). However, bacteria have developed mechanisms of AMP resistance, including the removal of AMPs to the extracellular space by efflux pumps such as the MtrCDE or AcrAB-TolC systems, and the internalization of AMPs to the cytoplasm by the Sap transporter, followed by proteolytic digestion. In this review, we focus on AMP transport as a resistance mechanism compiling all the experimental evidence for the involvement of efflux in AMP resistance in Gram-negative bacteria and combine this information with the analysis of the structures of the efflux systems involved. Finally, we expose some open questions with the aim of arousing the interest of the scientific community towards the AMPs-efflux pumps interactions. All the collected information broadens our understanding of AMP removal by efflux pumps and gives some clues to assist the rational design of AMP-derivatives as inhibitors of the efflux pumps.
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Affiliation(s)
- Jessica M A Blair
- College of Medical and Dental Sciences, Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Kornelius Zeth
- Department of Science and Environment, Roskilde University, Universitetsvej 1, 4000 Roskilde, Denmark
| | - Vassiliy N Bavro
- School of Life Sciences, University of Essex, Colchester, CO4 3SQ, United Kingdom
| | - Enea Sancho-Vaello
- Corresponding author. College of Medical and Dental Sciences, Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom. E-mail:
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6
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Sikdar S, Banerjee M, Vemparala S. Role of Disulphide Bonds in Membrane Partitioning of a Viral Peptide. J Membr Biol 2022; 255:129-142. [PMID: 35218393 PMCID: PMC8881898 DOI: 10.1007/s00232-022-00218-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 02/02/2022] [Indexed: 01/22/2023]
Abstract
The importance of disulphide bond in mediating viral peptide entry into host cells is well known. In the present work, we elucidate the role of disulphide (SS) bond in partitioning mechanism of membrane-active Hepatitis A Virus-2B (HAV-2B) peptide, which harbours three cysteine residues promoting formation of multiple SS-bonded states. The inclusion of SS-bond not only results in a compact conformation but also induces distorted α-helical hairpin geometry in comparison to SS-free state. Owing to these, the hydrophobic residues get buried, restricting the insertion of SS-bonded HAV-2B peptide into lipid packing defects and thus the partitioning of the peptide is completely or partly abolished. In this way, the disulphide bond can potentially regulate the partitioning of HAV-2B peptide such that the membrane remodelling effects of this viral peptide are significantly reduced. The current findings may have potential implications in drug designing, targeting the HAV-2B protein by promoting disulphide bond formation within its membrane-active region.
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Affiliation(s)
- Samapan Sikdar
- The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai, 600113, India. .,Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, 400094, India.
| | - Manidipa Banerjee
- Kusuma School of Biological Sciences, Indian Institute of Technology-Delhi, Hauz Khas, New Delhi, 110016, India.
| | - Satyavani Vemparala
- The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai, 600113, India. .,Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, 400094, India.
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7
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Booth V. Deuterium Solid State NMR Studies of Intact Bacteria Treated With Antimicrobial Peptides. FRONTIERS IN MEDICAL TECHNOLOGY 2022; 2:621572. [PMID: 35047897 PMCID: PMC8757836 DOI: 10.3389/fmedt.2020.621572] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 12/10/2020] [Indexed: 11/13/2022] Open
Abstract
Solid state NMR has been tremendously useful in characterizing the structure and dynamics of model membranes composed of simple lipid mixtures. Model lipid studies employing solid state NMR have included important work revealing how membrane bilayer structure and dynamics are affected by molecules such as antimicrobial peptides (AMPs). However, solid state NMR need not be applied only to model membranes, but can also be used with living, intact cells. NMR of whole cells holds promise for helping resolve some unsolved mysteries about how bacteria interact with AMPs. This mini-review will focus on recent studies using 2H NMR to study how treatment with AMPs affect membranes in intact bacteria.
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Affiliation(s)
- Valerie Booth
- Department of Biochemistry and Department of Physics and Physical Oceanograpy, Memorial University of Newfoundland, St. John's, NL, Canada
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8
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Brewer A, Zhang L. Binding free energy calculation of human beta defensin 3 with negatively charged lipid bilayer using free energy perturbation method. Biophys Chem 2021; 277:106662. [PMID: 34399250 DOI: 10.1016/j.bpc.2021.106662] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 01/05/2023]
Abstract
Human β defensin type 3 (hBD-3) is a cationic peptide having strong antimicrobial activities even at high salt concentrations. The conserved sequence is believed to contribute to its unique antibacterial activities. To design novel drugs based on hBD-3, predicting the binding free energy contribution of each residue on hBD-3 with bacterial membrane is important. Firstly, the stable binding structure of hBD-3 dimer in analog form bound on POPG lipid bilayer was predicted using NAMD simulations, which was confirmed by RMSD, buried surface area, hydrogen bonds, distance map, and insertion depth map calculations. Then, free energy perturbation (FEP) method was applied to calculate the binding free energy of each residue by mutating it into Alanine. It was found that the positively charged residues on the tail region of hBD-3 contribute significantly to its binding with membrane. The result emphasized the importance of electrostatic interactions to hBD-3's binding with bacterial membrane.
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Affiliation(s)
- Ann Brewer
- Chemical Engineering Department, Tennessee Technological University, Cookeville, TN 38505, United States of America
| | - Liqun Zhang
- Chemical Engineering Department, Tennessee Technological University, Cookeville, TN 38505, United States of America.
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9
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Zhang L. Interaction of Human β Defensin Type 3 (hBD-3) with Different PIP2-Containing Membranes, a Molecular Dynamics Simulation Study. J Chem Inf Model 2021; 61:4670-4686. [PMID: 34473496 DOI: 10.1021/acs.jcim.1c00805] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Human β defensin type 3 (hBD-3) is a cysteine-rich small antibacterial peptide. It belongs to the human innate immune system. hBD-3 has six cysteine residues, which form three pairs of disulfide bonds, and those bonds break in the reducing condition. It is known that hBD-3 can interact with bacterial membrane, and even eukaryotic cell membrane, which has a low concentration of phosphatidylinositol 4,5-bisphosphate (PIP2) lipids. PIP2 is a vital component in cell membranes and has been found to play important roles during antimicrobial peptide (AMP) interaction with membranes. To understand the functional mechanism of hBD-3 interacting with PIP2-containing membranes, the binding structures of hBD-3 on 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) bilayers mixed with 10% of PIP2 were predicted using two kinds of methods. The first one is by placing the hBD-3 monomer in different orientations above the POPC + 10%PIP2 membrane to set up five different initial simulation systems and performing long-term simulations on each to predict the most stable binding structure. It was found that hBD-3 analogue binds on the mixed lipid membrane on the two loop regions. The second method is by running long-term simulations on one or nine hBD-3 dimers binding on POPC mixed with 10%PIP2 lipid bilayer starting from the solid-state NMR (ssNMR)-suggested orientation. The dimer dissociated, and the most stable binding of hBD-3 in wild-type on the mixed membrane is also through the two loop regions, which agrees with the prediction from both the first method and the lipid self-assembly result. The PIP2 lipids can form long-lasting hydrogen bonds with positively charged residues such as Arg and Lys on hBD-3, thus forming clusters with hBD-3. As a comparison, hBD-3 dimers binding with a combined bilayer having 1,2-palmitoyl-oleoyl-sn-glycero-3-phosphoserine (POPS) on the upper and POPC on the lower leaflets and the combined POPS + POPC bilayer mixing with 10%PIP2 were also studied. The long-term simulation result shows that hBD-3 can bind with the heads of negatively charged POPS and PIP2 lipids and form hydrogen bonds. The stable binding sites of hBD-3 on PIP2 or POPS mixed bilayers are still on the two loop regions. On the combined POPS + POPC mixed with 10%PIP2 bilayer, the binding of hBD-3 with PIP2 lipids became less stable and fewer because of the competition of binding with the POPS lipids. Besides that, binding with hBD-3 can decrease the membrane thickness of the POPC + PIP2, POPS + POPC, and POPS + POPC + PIP2 bilayers and make POPS and PIP2 lipids more flexible based on the order parameter calculations. Our results supply molecular insight on AMP binding with different membranes and can help understand the functional mechanism of hBD-3 disrupting PIP2-containing membranes.
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Affiliation(s)
- Liqun Zhang
- Department of Chemical Engineering, Tennessee Technological University, Cookeville, Tennessee 38505, United States
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10
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Susapto HH, Alhattab D, Abdelrahman S, Khan Z, Alshehri S, Kahin K, Ge R, Moretti M, Emwas AH, Hauser CAE. Ultrashort Peptide Bioinks Support Automated Printing of Large-Scale Constructs Assuring Long-Term Survival of Printed Tissue Constructs. NANO LETTERS 2021; 21:2719-2729. [PMID: 33492960 DOI: 10.1021/acs.nanolett.0c04426] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We report about rationally designed ultrashort peptide bioinks, overcoming severe limitations in current bioprinting procedures. Bioprinting is increasingly relevant in tissue engineering, regenerative and personalized medicine due to its ability to fabricate complex tissue scaffolds through an automated deposition process. Printing stable large-scale constructs with high shape fidelity and enabling long-term cell survival are major challenges that most existing bioinks are unable to solve. Additionally, they require chemical or UV-cross-linking for the structure-solidifying process which compromises the encapsulated cells, resulting in restricted structure complexity and low cell viability. Using ultrashort peptide bioinks as ideal bodylike but synthetic material, we demonstrate an instant solidifying cell-embedding printing process via a sophisticated extrusion procedure under true physiological conditions and at cost-effective low bioink concentrations. Our printed large-scale cell constructs and the chondrogenic differentiation of printed mesenchymal stem cells point to the strong potential of the peptide bioinks for automated complex tissue fabrication.
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Affiliation(s)
- Hepi H Susapto
- Laboratory for Nanomedicine, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Dana Alhattab
- Laboratory for Nanomedicine, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Sherin Abdelrahman
- Laboratory for Nanomedicine, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Zainab Khan
- Laboratory for Nanomedicine, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Salwa Alshehri
- Laboratory for Nanomedicine, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Kowther Kahin
- Laboratory for Nanomedicine, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Rui Ge
- Laboratory for Nanomedicine, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Manola Moretti
- Laboratory for Nanomedicine, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Abdul-Hamid Emwas
- Core Laboratories, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Charlotte A E Hauser
- Laboratory for Nanomedicine, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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11
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Separovic F, Keizer DW, Sani MA. In-cell Solid-State NMR Studies of Antimicrobial Peptides. FRONTIERS IN MEDICAL TECHNOLOGY 2020; 2:610203. [PMID: 35047891 PMCID: PMC8757805 DOI: 10.3389/fmedt.2020.610203] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 11/30/2020] [Indexed: 12/23/2022] Open
Abstract
Antimicrobial peptides (AMPs) have attracted attention as alternatives to classic antibiotics due to their expected limited pressure on bacterial resistance mechanisms. Yet, their modes of action, in particular in vivo, remain to be elucidated. In situ atomistic-scale details of complex biomolecular assemblies is a challenging requirement for deciphering the complex modes of action of AMPs. The large diversity of molecules that modulate complex interactions limits the resolution achievable using imaging methodology. Herein, the latest advances in in-cell solid-state NMR (ssNMR) are discussed, which demonstrate the power of this non-invasive technique to provide atomic details of molecular structure and dynamics. Practical requirements for investigations of intact bacteria are discussed. An overview of recent in situ NMR investigations of the architecture and metabolism of bacteria and the effect of AMPs on various bacterial structures is presented. In-cell ssNMR revealed that the studied AMPs have a disruptive action on the molecular packing of bacterial membranes and DNA. Despite the limited number of studies, in-cell ssNMR is emerging as a powerful technique to monitor in situ the interplay between bacteria and AMPs.
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Affiliation(s)
- Frances Separovic
- School of Chemistry, University of Melbourne, Melbourne, VIC, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, VIC, Australia
| | - David W. Keizer
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Marc-Antoine Sani
- School of Chemistry, University of Melbourne, Melbourne, VIC, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, VIC, Australia
- *Correspondence: Marc-Antoine Sani
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12
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Mücke PA, Ostrzinski A, Hammerschmidt S, Maaß S, Becher D. Proteomic Adaptation of Streptococcus pneumoniae to the Antimicrobial Peptide Human Beta Defensin 3 (hBD3) in Comparison to Other Cell Surface Stresses. Microorganisms 2020; 8:microorganisms8111697. [PMID: 33143252 PMCID: PMC7694020 DOI: 10.3390/microorganisms8111697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 10/23/2020] [Accepted: 10/27/2020] [Indexed: 02/06/2023] Open
Abstract
The antimicrobial peptide human Beta defensin 3 (hBD3) is an essential part of the innate immune system and is involved in protection against respiratory pathogens by specifically permeabilizing bacterial membranes. The Gram-positive bacterium Streptococcus pneumoniae causes serious diseases including pneumonia, meningitis, and septicemia, despite being frequently exposed to human defense molecules, including hBD3 during colonization and infection. Thus, the question arises how pneumococci adapt to stress caused by antimicrobial peptides. We addressed this subject by analyzing the proteome of S. pneumoniae after treatment with hBD3 and compared our data with the proteomic changes induced by LL-37, another crucial antimicrobial peptide present in the human respiratory tract. As antimicrobial peptides usually cause membrane perturbations, the response to the membrane active cationic detergent cetyltrimethylammonium bromide (CTAB) was examined to assess the specificity of the pneumococcal response to antimicrobial peptides. In brief, hBD3 and LL-37 induce a similar response in pneumococci and especially, changes in proteins with annotated transporter and virulence function have been identified. However, LL-37 causes changes in the abundance of cell surface modification proteins that cannot be observed after treatment with hBD3. Interestingly, CTAB induces unique proteomic changes in S. pneumoniae. Though, the detergent seems to activate a two-component system that is also activated in response to antimicrobial peptide stress (TCS 05). Overall, our data represent a novel resource on pneumococcal adaptation to specific cell surface stresses on a functional level. This knowledge can potentially be used to develop strategies to circumvent pneumococcal resistance to antimicrobial peptides.
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Affiliation(s)
- Pierre-Alexander Mücke
- Department of Microbial Proteomics, Institute of Microbiology, Center for Functional Genomics of Microbes, University of Greifswald, Felix-Hausdorff-Str. 8, 17489 Greifswald, Germany
| | - Anne Ostrzinski
- Department of Microbial Proteomics, Institute of Microbiology, Center for Functional Genomics of Microbes, University of Greifswald, Felix-Hausdorff-Str. 8, 17489 Greifswald, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Felix-Hausdorff-Str. 8, 17489 Greifswald, Germany
| | - Sandra Maaß
- Department of Microbial Proteomics, Institute of Microbiology, Center for Functional Genomics of Microbes, University of Greifswald, Felix-Hausdorff-Str. 8, 17489 Greifswald, Germany
| | - Dörte Becher
- Department of Microbial Proteomics, Institute of Microbiology, Center for Functional Genomics of Microbes, University of Greifswald, Felix-Hausdorff-Str. 8, 17489 Greifswald, Germany
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13
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Yun H, Min HJ, Lee CW. NMR structure and bactericidal activity of KR-12 analog derived from human LL-37 as a potential cosmetic preservative. J Anal Sci Technol 2020. [DOI: 10.1186/s40543-020-00213-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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14
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Monitoring the Site-Specific Solid-State NMR Data in Oligopeptides. Int J Mol Sci 2020; 21:ijms21082700. [PMID: 32295042 PMCID: PMC7215618 DOI: 10.3390/ijms21082700] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/06/2020] [Accepted: 04/09/2020] [Indexed: 02/07/2023] Open
Abstract
Reliable values of the solid-state NMR (SSNMR) parameters together with precise structural data specific for a given amino acid site in an oligopeptide are needed for the proper interpretation of measurements aiming at an understanding of oligopeptides' function. The periodic density functional theory (DFT)-based computations of geometries and SSNMR chemical shielding tensors (CSTs) of solids are shown to be accurate enough to support the SSNMR investigations of suitably chosen models of oriented samples of oligopeptides. This finding is based on a thorough comparison between the DFT and experimental data for a set of tripeptides with both 13Cα and 15Namid CSTs available from the single-crystal SSNMR measurements and covering the three most common secondary structural elements of polypeptides. Thus, the ground is laid for a quantitative description of local spectral parameters of crystalline oligopeptides, as demonstrated for the backbone 15Namid nuclei of samarosporin I, which is a pentadecapeptide (composed of five classical and ten nonproteinogenic amino acids) featuring a strong antimicrobial activity.
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15
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Siemer AB. Advances in studying protein disorder with solid-state NMR. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2020; 106:101643. [PMID: 31972419 PMCID: PMC7202078 DOI: 10.1016/j.ssnmr.2020.101643] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/06/2020] [Accepted: 01/07/2020] [Indexed: 05/26/2023]
Abstract
Solution NMR is a key tool to study intrinsically disordered proteins (IDPs), whose importance for biological function is widely accepted. However, disordered proteins are not limited to solution and are also found in non-soluble systems such as fibrils and membrane proteins. In this Trends article, I will discuss how solid-state NMR can be used to study disorder in non-soluble proteins. Techniques based on dipolar couplings can study static protein disorder which either occurs naturally as e.g. in spider silk or can be induced by freeze trapping IDPs or unfolded proteins. In this case, structural ensembles are directly reflected by a static distribution of dihedral angels that can be determined by the distribution of chemical shifts or other methods. Techniques based on J-couplings can detect dynamic protein disorder under MAS. In this case, only average chemical shifts are measured but disorder can be characterized with a variety of data including secondary chemical shifts, relaxation rates, paramagnetic relaxation enhancements, or residual dipolar couplings. I describe both technical aspects and examples of solid-state NMR on protein disorder and end the article with a discussion of challenges and opportunities of this emerging field.
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Affiliation(s)
- Ansgar B Siemer
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Univeristy of Southern California, 1501 San Pablo Street, Los Angeles, CA, 90033, USA.
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16
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Nehls C, Böhling A, Podschun R, Schubert S, Grötzinger J, Schromm A, Fedders H, Leippe M, Harder J, Kaconis Y, Gronow S, Gutsmann T. Influence of disulfide bonds in human beta defensin-3 on its strain specific activity against Gram-negative bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183273. [PMID: 32171739 DOI: 10.1016/j.bbamem.2020.183273] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 03/06/2020] [Accepted: 03/09/2020] [Indexed: 12/21/2022]
Abstract
Antimicrobial peptides (AMPs) play an important role in the host defense against various microbes. One of the most efficient human AMPs is the human beta defensin-3 (hBD-3) which is produced by, e.g. keratinocytes and lung epithelial cells. However, the structure-function relationship for AMPs and in particular for defensins with their typical three disulfide bonds is still poorly understood. In this study the importance of the three disulfide bonds for the activity of the AMPs is investigated with biological assays and with biophysical experiments utilizing different membrane reconstitution systems. The activities of natural hBD-3, hBD-3-c (cyclic variant with one disulfide bond), and hBD-3-l (linear variant without disulfide bonds) and fragments thereof were tested against specific Gram-negative bacteria. Furthermore, hemolytic and cytotoxic activities were analyzed as well as the potency to neutralize immune cell stimulation of lipopolysaccharide (LPS). Experiments using reconstituted lipid matrices composed of phospholipids or LPS purified from the respective Gram-negative bacteria, showed that the membrane activity of all three hBD-3 peptides is decisive for their capability to kill bacteria and to neutralize LPS. In most of the test systems the linear hBD-3-l showed the highest activity. It was also the only peptide significantly active against polymyxin B-resistant Proteus mirabilis R45. However, the stability of hBD-3 against protease activity decreases with decreasing number of disulfide bonds. This study demonstrates that the refining of AMP structures can generate more active compounds against certain strains.
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Affiliation(s)
- Christian Nehls
- Research Center Borstel, Leibniz Lung Center, Parkallee 10, 23845 Borstel, Germany
| | - Arne Böhling
- Research Center Borstel, Leibniz Lung Center, Parkallee 10, 23845 Borstel, Germany
| | - Rainer Podschun
- Institute for Infection Medicine, Christian-Albrechts University, Brunswiker Straße 4, 24105 Kiel, Germany
| | - Sabine Schubert
- Institute for Infection Medicine, Christian-Albrechts University, Brunswiker Straße 4, 24105 Kiel, Germany
| | - Joachim Grötzinger
- Institute of Biochemistry, Christian-Albrechts University, Ohlshausenstr. 40, 24098 Kiel, Germany
| | - Andra Schromm
- Research Center Borstel, Leibniz Lung Center, Parkallee 10, 23845 Borstel, Germany
| | - Henning Fedders
- Department of Zoophysiology, Christian-Albrechts University, Olshausenstraße 40, 24098 Kiel, Germany
| | - Matthias Leippe
- Department of Zoophysiology, Christian-Albrechts University, Olshausenstraße 40, 24098 Kiel, Germany
| | - Jürgen Harder
- Clinical Research Unit at the Department of Dermatology, Schittenhelmstr. 7, 24105 Kiel, Germany
| | - Yani Kaconis
- Research Center Borstel, Leibniz Lung Center, Parkallee 10, 23845 Borstel, Germany
| | - Sabine Gronow
- DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Medizinische Mikrobiologie, Inhoffenstr. 7b, 38124 Braunschweig, Germany
| | - Thomas Gutsmann
- Research Center Borstel, Leibniz Lung Center, Parkallee 10, 23845 Borstel, Germany.
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17
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Zhang L. Disulfide Bonds Affect the Binding Sites of Human β Defensin Type 3 on Negatively Charged Lipid Membranes. J Phys Chem B 2020; 124:2088-2100. [PMID: 32091905 DOI: 10.1021/acs.jpcb.9b10529] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Human β defensin type 3 (hBD-3) is a small natural antimicrobiotic. It is strongly cationic and has six cysteine residues which can form three pairs of intramolecular disulfide bonds under oxidized condition. Those disulfide bonds can break under reducing condition. However, the antibacterial activities of hBD-3 in its wild-type and analog forms are similar. In this project, the structure and dynamics of hBD-3 were investigated by running simulations on hBD-3 in its wild-type and analog forms in solvent, binding to negatively charged lipid bilayers, and self-assembly with POPG lipids. It was found that the RMSFs of hBD-3 in both its wild-type and analog forms are similar in solvent, while they are very diverse depending on the binding sites of hBD-3 with negatively charged bilayers. Calculating both the distance map and insertion depths for 18 hBD-3 molecules binding on the POPG bilayer, hBD-3 in its analog form binds stably with the POPG bilayer through the head and loop regions, while hBD-3 wild-type binds with the POPG bilayer on the two loop regions stably. hBD-3 analog caused membrane thinning and disrupted the POPG lipids more significantly than the wildtype. Based on the self-assembly simulations, hBD-3 monomer can bind with and embed inside the negatively charged POPG lipid membrane and have more contacts with the POPG lipid heads than with tails. The current work emphasized the structural diversity of hBD-3 interacting with negatively charged lipid membrane affected by the disulfide bonding states.
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Affiliation(s)
- Liqun Zhang
- Department of Chemical Engineering, Tennessee Technological University, Cookeville, Tennessee 38505, United States
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