1
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Schaefer S, Melodia D, Pracey C, Corrigan N, Lenardon MD, Boyer C. Mimicking Charged Host-Defense Peptides to Tune the Antifungal Activity and Biocompatibility of Amphiphilic Polymers. Biomacromolecules 2024; 25:871-889. [PMID: 38165721 DOI: 10.1021/acs.biomac.3c01038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
Invasive fungal infections impose a substantial global health burden. They cause more than 1.5 million deaths annually and are insufficiently met by the currently approved antifungal drugs. Antifungal peptides are a promising alternative to existing antifungal drugs; however, they can be challenging to synthesize, and are often susceptible to proteases in vivo. Synthetic polymers which mimic the properties of natural antifungal peptides can circumvent these limitations. In this study, we developed a library of 29 amphiphilic polyacrylamides with different charged units, namely, amines, guanidinium, imidazole, and carboxylic acid groups, representative of the natural amino acids lysine, arginine, histidine, and glutamic acid. Ternary polymers incorporating primary ammonium (lysine-like) or imidazole (histidine-like) groups demonstrated superior activity against Candida albicans and biocompatibility with mammalian cells compared to the polymers containing the other charged groups. Furthermore, a combination of primary ammonium, imidazole, and guanidinium (arginine-like) within the same polymer outperformed the antifungal drug amphotericin B in terms of therapeutic index and exhibited fast C. albicans-killing activity. The most promising polymer compositions showed synergistic effects in combination with caspofungin and fluconazole against C. albicans and additionally demonstrated activity against other clinically relevant fungi. Collectively, these results indicate the strong potential of these easily producible polymers to be used as antifungals.
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Affiliation(s)
- Sebastian Schaefer
- School of Chemical Engineering, University of New South Wales (UNSW), Sydney, New South Wales 2052, Australia
- Australian Centre for NanoMedicine, UNSW, Sydney, New South Wales 2052, Australia
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, New South Wales 2052, Australia
| | - Daniele Melodia
- School of Chemical Engineering, University of New South Wales (UNSW), Sydney, New South Wales 2052, Australia
- Australian Centre for NanoMedicine, UNSW, Sydney, New South Wales 2052, Australia
| | - Christopher Pracey
- Nuclear Magnetic Resonance Facility, Mark Wainwright Analytical Centre, UNSW, Sydney, New South Wales 2052, Australia
| | - Nathaniel Corrigan
- School of Chemical Engineering, University of New South Wales (UNSW), Sydney, New South Wales 2052, Australia
- Australian Centre for NanoMedicine, UNSW, Sydney, New South Wales 2052, Australia
| | - Megan D Lenardon
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, New South Wales 2052, Australia
| | - Cyrille Boyer
- School of Chemical Engineering, University of New South Wales (UNSW), Sydney, New South Wales 2052, Australia
- Australian Centre for NanoMedicine, UNSW, Sydney, New South Wales 2052, Australia
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2
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Wang A, Zhou M, Chen Q, Jin H, Xu G, Guo R, Wang J, Lai R. Functional Analyses of Three Targeted DNA Antimicrobial Peptides Derived from Goats. Biomolecules 2023; 13:1453. [PMID: 37892141 PMCID: PMC10605153 DOI: 10.3390/biom13101453] [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: 07/23/2023] [Revised: 09/03/2023] [Accepted: 09/14/2023] [Indexed: 10/29/2023] Open
Abstract
With the increase in drug-resistant bacteria, new antibacterial drugs have emerged as a prominent area of research and development. Antimicrobial peptides (AMPs), as innate immune agents, have garnered significant attention due to their potent, rapid, and broad-spectrum antibacterial activity. This study focused on investigating the functionality of three AMPs (CATH 1, CATH 2, and MAP34-B) derived from goat submandibular glands. Among these AMPs, CATH 2 and MAP34-B exhibited direct antibacterial activity against both Gram-negative and Gram-positive bacteria, primarily targeting the bacterial membrane. Additionally, these two AMPs were found to have the potential to induce reactive oxygen species (ROS) production in bacterial cells and interact with bacterial genome DNA, which may play a crucial role in their mechanisms of action. Furthermore, both CATH 1 and CATH 2 demonstrated significant antioxidant activity, and all three AMPs exhibited potential anti-inflammatory activity. Importantly, the cytotoxic activity of these AMPs against mammalian cells was found to be weak, and their hemolytic activity was extremely low. Overall, the characteristics of these three AMPs found in goat submandibular glands offer new insights for the study of host protection from an immunological perspective. They hold promise as potential candidates for the development of novel antibacterial agents, particularly in the context of combating drug-resistant bacteria.
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Affiliation(s)
- Aili Wang
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Mengying Zhou
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou 215137, China
| | - Qian Chen
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Hui Jin
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Gaochi Xu
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Ruiyin Guo
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Jianmin Wang
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian 271000, China;
| | - Ren Lai
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
- Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Kunming 650107, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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3
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Campbell JX, Gao S, Anand KS, Franz KJ. Zinc Binding Inhibits Cellular Uptake and Antifungal Activity of Histatin-5 in Candida albicans. ACS Infect Dis 2022; 8:1920-1934. [PMID: 35997625 PMCID: PMC9671271 DOI: 10.1021/acsinfecdis.2c00289] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Histatin-5 (Hist-5) is a polycationic, histidine-rich antimicrobial peptide with potent antifungal activity against the opportunistic fungal pathogen Candida albicans. Hist-5 can bind metals in vitro, and metals have been shown to alter the fungicidal activity of the peptide. Previous reports on the effect of Zn2+ on Hist-5 activity have been varied and seemingly contradictory. Here, we present data elucidating the dynamic role Zn2+ plays as an inhibitory switch to regulate Hist-5 fungicidal activity. A novel fluorescently labeled Hist-5 peptide (Hist-5*) was developed to visualize changes in internalization and localization of the peptide as a function of metal availability in the growth medium. Hist-5* was verified for use as a model peptide and retained antifungal activity and mode of action similar to native Hist-5. Cellular growth assays showed that Zn2+ had a concentration-dependent inhibitory effect on Hist-5 antifungal activity. Imaging by confocal microscopy revealed that equimolar concentrations of Zn2+ kept the peptide localized along the cell periphery rather than internalizing, thus preventing cytotoxicity and membrane disruption. However, the Zn-induced decrease in Hist-5 activity and uptake was rescued by decreasing the Zn2+ availability upon addition of a metal chelator EDTA or S100A12, a Zn-binding protein involved in the innate immune response. These results lead us to suggest a model wherein commensal C. albicans may exist in harmony with Hist-5 at concentrations of Zn2+ that inhibit peptide internalization and antifungal activity. Activation of host immune processes that initiate Zn-sequestering mechanisms of nutritional immunity could trigger Hist-5 internalization and cell killing.
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4
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Hunting for Novel Routes in Anticancer Drug Discovery: Peptides against Sam-Sam Interactions. Int J Mol Sci 2022; 23:ijms231810397. [PMID: 36142306 PMCID: PMC9499636 DOI: 10.3390/ijms231810397] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/02/2022] [Accepted: 09/02/2022] [Indexed: 01/10/2023] Open
Abstract
Among the diverse protein binding modules, Sam (Sterile alpha motif) domains attract attention due to their versatility. They are present in different organisms and play many functions in physiological and pathological processes by binding multiple partners. The EphA2 receptor contains a Sam domain at the C-terminus (EphA2-Sam) that is able to engage protein regulators of receptor stability (including the lipid phosphatase Ship2 and the adaptor Odin). Ship2 and Odin are recruited by EphA2-Sam through heterotypic Sam-Sam interactions. Ship2 decreases EphA2 endocytosis and consequent degradation, producing chiefly pro-oncogenic outcomes in a cellular milieu. Odin, through its Sam domains, contributes to receptor stability by possibly interfering with ubiquitination. As EphA2 is upregulated in many types of tumors, peptide inhibitors of Sam-Sam interactions by hindering receptor stability could function as anticancer therapeutics. This review describes EphA2-Sam and its interactome from a structural and functional perspective. The diverse design strategies that have thus far been employed to obtain peptides targeting EphA2-mediated Sam-Sam interactions are summarized as well. The generated peptides represent good initial lead compounds, but surely many efforts need to be devoted in the close future to improve interaction affinities towards Sam domains and consequently validate their anticancer properties.
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5
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Fagerberg E, Lenton S, Nylander T, Seydel T, Skepö M. Self-Diffusive Properties of the Intrinsically Disordered Protein Histatin 5 and the Impact of Crowding Thereon: A Combined Neutron Spectroscopy and Molecular Dynamics Simulation Study. J Phys Chem B 2022; 126:789-801. [PMID: 35044776 PMCID: PMC8819652 DOI: 10.1021/acs.jpcb.1c08976] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
![]()
Intrinsically disordered
proteins (IDPs) are proteins that, in
comparison with globular/structured proteins, lack a distinct tertiary
structure. Here, we use the model IDP, Histatin 5, for studying its
dynamical properties under self-crowding conditions with quasi-elastic
neutron scattering in combination with full atomistic molecular dynamics
(MD) simulations. The aim is to determine the effects of crowding
on the center-of-mass diffusion as well as the internal diffusive
behavior. The diffusion was found to decrease significantly, which
we hypothesize can be attributed to some degree of aggregation at
higher protein concentrations, (≥100 mg/mL), as indicated by
recent small-angle X-ray scattering studies. Temperature effects are
also considered and found to, largely, follow Stokes–Einstein
behavior. Simple geometric considerations fail to accurately predict
the rates of diffusion, while simulations show semiquantitative agreement
with experiments, dependent on assumptions of the ratio between translational
and rotational diffusion. A scaling law that previously was found
to successfully describe the behavior of globular proteins was found
to be inadequate for the IDP, Histatin 5. Analysis of the MD simulations
show that the width of the distribution with respect to diffusion
is not a simplistic mirroring of the distribution of radius of gyration,
hence, displaying the particular features of IDPs that need to be
accounted for.
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Affiliation(s)
- Eric Fagerberg
- Theoretical Chemistry, Lund University, POB 124, SE-221 00 Lund, Sweden
| | - Samuel Lenton
- Physical Chemistry, Lund University, POB 124, SE-221 00 Lund, Sweden
| | - Tommy Nylander
- Physical Chemistry, Lund University, POB 124, SE-221 00 Lund, Sweden
| | - Tilo Seydel
- Institut Max von Laue - Paul Langevin, 71 avenue des Martyrs, CS 20156, F-38042 Grenoble, France
| | - Marie Skepö
- Theoretical Chemistry, Lund University, POB 124, SE-221 00 Lund, Sweden.,LINXS - Lund Institute of Advanced Neutron and X-ray Science, Scheelevägen 19, SE-223 70 Lund, Sweden
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6
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Sharma P, Chaudhary M, Khanna G, Rishi P, Kaur IP. Envisaging Antifungal Potential of Histatin 5: A Physiological Salivary Peptide. J Fungi (Basel) 2021; 7:jof7121070. [PMID: 34947052 PMCID: PMC8707063 DOI: 10.3390/jof7121070] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 12/02/2021] [Accepted: 12/07/2021] [Indexed: 12/18/2022] Open
Abstract
Fungi are reported to cause a range of superficial to invasive human infections. These often result in high morbidity and at times mortality. Conventional antifungal agents though effective invariably exhibit drug interactions, treatment-related toxicity, and fail to elicit significant effect, thus indicating a need to look for suitable alternatives. Fungi thrive in humid, nutrient-enriched areas. Such an environment is well-supported by the oral cavity. Despite this, there is a relatively low incidence of severe oral and periodontal fungal infections, attributed to the presence of antimicrobial peptides hosted by saliva, viz. histatin 5 (Hstn 5). It displays fungicidal activity against a variety of fungi including Candida albicans, Candida glabrata, Candida krusei, Cryptococcus neoformans, and unicellular yeast-like Saccharomyces cerevisiae. Candida albicans alone accounts for about 70% of all global fungal infections including periodontal disease. This review intends to discuss the scope of Hstn 5 as a novel recourse for the control of fungal infections.
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Affiliation(s)
- Pratibha Sharma
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India; (P.S.); (M.C.); (G.K.)
| | - Mehak Chaudhary
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India; (P.S.); (M.C.); (G.K.)
| | - Garima Khanna
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India; (P.S.); (M.C.); (G.K.)
| | - Praveen Rishi
- Department of Microbiology, Panjab University, Chandigarh 160014, India
- Correspondence: (P.R.); (I.P.K.); Tel.: +91-172-2534-113 (P.R.); +91-985-5166-432 (I.P.K.)
| | - Indu Pal Kaur
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India; (P.S.); (M.C.); (G.K.)
- Correspondence: (P.R.); (I.P.K.); Tel.: +91-172-2534-113 (P.R.); +91-985-5166-432 (I.P.K.)
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7
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Nunes LGP, Reichert T, Machini MT. His-Rich Peptides, Gly- and His-Rich Peptides: Functionally Versatile Compounds with Potential Multi-Purpose Applications. Int J Pept Res Ther 2021. [DOI: 10.1007/s10989-021-10302-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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8
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Siqueira WL, Canales MP, Crosara KTB, Marin LM, Xiao Y. Proteome difference among the salivary proteins adsorbed onto metallic orthodontic brackets and hydroxyapatite discs. PLoS One 2021; 16:e0254909. [PMID: 34319997 PMCID: PMC8318307 DOI: 10.1371/journal.pone.0254909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 07/06/2021] [Indexed: 11/18/2022] Open
Abstract
The aim of this study was to investigate the atomic composition and the proteome of the salivary proteins adsorbed on the surface of orthodontic metallic bracket. For this, the atomic composition of orthodontic metallic brackets was analyzed with X-ray Photoelectron Spectroscopy (XPS). The acquired bracket pellicle was characterized after brackets were immersed in human whole saliva supernatant for 2 hours at 37°C. Hydroxyapatite (HA) discs were used as a control. Acquired pellicle was harvested from the HA discs (n = 12) and from the metallic brackets (n = 12). Proteomics based on mass spectrometry technology was used for salivary protein identification and characterization. Results showed that most of the proteins adsorbed on the surface of orthodontic metallic brackets and on the HA discs were identified specifically to each group, indicating a small overlapping between the salivary proteins on each study group. A total of 311 proteins present on the HA discs were unique to this group while 253 proteins were unique to metallic brackets, and only 45 proteins were common to the two groups. Even though most proteins were unique to each study group, proteins related to antimicrobial activity, lubrication, and remineralization were present in both groups. These findings demonstrate that the salivary proteins adsorbed on the bracket surface are dependent on the material molecular composition.
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Affiliation(s)
- Walter Luiz Siqueira
- College of Dentistry, University of Saskatchewan, Saskatoon, SK, Canada
- * E-mail:
| | - Maria Pia Canales
- Schulich Dentistry & Medicine, The University of Western Ontario, London, ON, Canada
| | | | - Lina Maria Marin
- College of Dentistry, University of Saskatchewan, Saskatoon, SK, Canada
| | - Yizhi Xiao
- Schulich Dentistry & Medicine, The University of Western Ontario, London, ON, Canada
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9
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Sharma KK, Ravi R, Maurya IK, Kapadia A, Khan SI, Kumar V, Tikoo K, Jain R. Modified histidine containing amphipathic ultrashort antifungal peptide, His[2-p-(n-butyl)phenyl]-Trp-Arg-OMe exhibits potent anticryptococcal activity. Eur J Med Chem 2021; 223:113635. [PMID: 34147743 DOI: 10.1016/j.ejmech.2021.113635] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 05/31/2021] [Accepted: 06/06/2021] [Indexed: 12/26/2022]
Abstract
In pursuit of ultrashort peptide-based antifungals, a new structural class, His(2-aryl)-Trp-Arg is reported. Structural changes were investigated on His-Trp-Arg scaffold to demonstrate the impact of charge and lipophilic character on the biological activity. The presence and size of the aryl moiety on imidazole of histidine modulated overall amphiphilic character, and biological activity. Peptides exhibited IC50 of 0.37-9.66 μg/mL against C. neoformans. Peptide 14f [His(2-p-(n-butyl)phenyl)-Trp-Arg-OMe] exhibited two-fold potency (IC50 = 0.37 μg/mL, MIC = 0.63 μg/mL) related to amphotericin B, without any cytotoxic effects up to 10 μg/mL. Peptide 14f act by nuclear fragmentation, membranes permeabilization, disruption and pore formations in the microbial cells as determined by the mechanistic studies employing Trp-quenching, CLSM, SEM, and HR-TEM. The amalgamation of short sequence, presence of appropriate aryl group on l-histidine, potent anticryptococcal activity, no cytotoxicity, and detailed mechanistic studies directed to the identification of 14f as a new antifungal structural lead.
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Affiliation(s)
- Krishna K Sharma
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Ravikant Ravi
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Indresh Kumar Maurya
- Department of Microbial Technology, Panjab University, Sector 25, Chandigarh 160 014, India
| | - Akshay Kapadia
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Shabana I Khan
- National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Vinod Kumar
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S Nagar 160 062, Punjab India
| | - Kulbhushan Tikoo
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S Nagar 160 062, Punjab India
| | - Rahul Jain
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India.
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10
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Siwakul P, Sirinnaphakorn L, Suwanprateep J, Hayakawa T, Pugdee K. Cellular responses of histatin-derived peptides immobilized titanium surface using a tresyl chloride-activated method. Dent Mater J 2021; 40:934-941. [PMID: 33814533 DOI: 10.4012/dmj.2020-307] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Effects of histatin-derived peptides immobilization by tresyl chloride-activation technique for MC3T3-E1 cellular responses on titanium (Ti) were evaluated. MC3T3-E1 were cultured on sandblasted and acid-etched Ti disks immobilized with histatin-derived peptides, including histatin-1, JH8194, and mixed histatin-1 with JH8194. Surface topography and cellular morphology were examined using a scanning electron microscope. Elemental composition and conformational peptides on Ti surface were examined using energy dispersive X-ray and fourier transform infrared spectroscopy, respectively. Cellular adhesion, proliferation, osteogenesis-related genes, and alkaline phosphatase activity were evaluated. The results showed that peptides were successfully immobilized on Ti surface. Cell attachments on histatin-1 and mixed peptides coated groups are higher than control. Histatin-1 achieved the significantly highest cellular proliferation. Histatin-derived peptides improved the osteogenesis related-gene expression and alkaline phosphatase activity (p<0.05). This study suggested that histatin-1 immobilization by tresyl chloride-activation technique enhanced cellular responses and might be able to promote cellular activities around the dental implants.
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Affiliation(s)
| | | | - Jintamai Suwanprateep
- Biomedical Engineering Research Unit, National Metal and Materials Technology Center, Ministry of Science and Technology
| | - Tohru Hayakawa
- Department of Dental Engineering, Tsurumi University School of Dental Medicine
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11
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Li S, Wang Y, Xue Z, Jia Y, Li R, He C, Chen H. The structure-mechanism relationship and mode of actions of antimicrobial peptides: A review. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.01.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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12
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Appadurai R, Nagesh J, Srivastava A. High resolution ensemble description of metamorphic and intrinsically disordered proteins using an efficient hybrid parallel tempering scheme. Nat Commun 2021; 12:958. [PMID: 33574233 PMCID: PMC7878814 DOI: 10.1038/s41467-021-21105-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 01/08/2021] [Indexed: 12/26/2022] Open
Abstract
Mapping free energy landscapes of complex multi-funneled metamorphic proteins and weakly-funneled intrinsically disordered proteins (IDPs) remains challenging. While rare-event sampling molecular dynamics simulations can be useful, they often need to either impose restraints or reweigh the generated data to match experiments. Here, we present a parallel-tempering method that takes advantage of accelerated water dynamics and allows efficient and accurate conformational sampling across a wide variety of proteins. We demonstrate the improved sampling efficiency by benchmarking against standard model systems such as alanine di-peptide, TRP-cage and β-hairpin. The method successfully scales to large metamorphic proteins such as RFA-H and to highly disordered IDPs such as Histatin-5. Across the diverse proteins, the calculated ensemble averages match well with the NMR, SAXS and other biophysical experiments without the need to reweigh. By allowing accurate sampling across different landscapes, the method opens doors for sampling free energy landscape of complex uncharted proteins.
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Affiliation(s)
- Rajeswari Appadurai
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka, India
| | - Jayashree Nagesh
- Solid State & Structural Chemistry Unit, Indian Institute of Science, Bangalore, Karnataka, India
| | - Anand Srivastava
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka, India.
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13
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Lu J, Xu H, Xia J, Ma J, Xu J, Li Y, Feng J. D- and Unnatural Amino Acid Substituted Antimicrobial Peptides With Improved Proteolytic Resistance and Their Proteolytic Degradation Characteristics. Front Microbiol 2020; 11:563030. [PMID: 33281761 PMCID: PMC7688903 DOI: 10.3389/fmicb.2020.563030] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 10/22/2020] [Indexed: 01/10/2023] Open
Abstract
The transition of antimicrobial peptides (AMPs) from the laboratory to market has been severely hindered by their instability toward proteases in biological systems. In the present study, we synthesized derivatives of the cationic AMP Pep05 (KRLFKKLLKYLRKF) by substituting L-amino acid residues with D- and unnatural amino acids, such as D-lysine, D-arginine, L-2,4-diaminobutanoic acid (Dab), L-2,3-diaminopropionic acid (Dap), L-homoarginine, 4-aminobutanoic acid (Aib), and L-thienylalanine, and evaluated their antimicrobial activities, toxicities, and stabilities toward trypsin, plasma proteases, and secreted bacterial proteases. In addition to measuring changes in the concentration of the intact peptides, LC-MS was used to identify the degradation products of the modified AMPs in the presence of trypsin and plasma proteases to determine degradation pathways and examine whether the amino acid substitutions afforded improved proteolytic resistance. The results revealed that both D- and unnatural amino acids enhanced the stabilities of the peptides toward proteases. The derivative DP06, in which all of the L-lysine and L-arginine residues were replaced by D-amino acids, displayed remarkable stability and mild toxicity in vitro but only slight activity and severe toxicity in vivo, indicating a significant difference between the in vivo and in vitro results. Unexpectedly, we found that the incorporation of a single Aib residue at the N-terminus of compound UP09 afforded remarkably enhanced plasma stability and improved activity in vivo. Hence, this derivative may represent a candidate AMP for further optimization, providing a new strategy for the design of novel AMPs with improved bioavailability.
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Affiliation(s)
- Jianguang Lu
- Key State Laboratory of Drug Innovation and Pharmaceutical Technology, China State Institute of Pharmaceutical Industry, Shanghai, China.,Department of Peptide Drugs R&D, Shanghai Duomirui Biotechnology Co., Ltd., Shanghai, China
| | - Hongjiang Xu
- Key State Laboratory of Drug Innovation and Pharmaceutical Technology, China State Institute of Pharmaceutical Industry, Shanghai, China.,Department of Drug Evaluation and Research, Chia Tai Tianqing Pharmaceutical Group Co., Ltd., Nanjing, China
| | - Jianghua Xia
- Key State Laboratory of Drug Innovation and Pharmaceutical Technology, China State Institute of Pharmaceutical Industry, Shanghai, China
| | - Jie Ma
- Department of Peptide Drugs R&D, Shanghai Duomirui Biotechnology Co., Ltd., Shanghai, China
| | - Jun Xu
- Department of Peptide Drugs R&D, Shanghai Duomirui Biotechnology Co., Ltd., Shanghai, China
| | - Yanan Li
- Key State Laboratory of Drug Innovation and Pharmaceutical Technology, China State Institute of Pharmaceutical Industry, Shanghai, China.,School of Pharmacy, Fudan University, Shanghai, China
| | - Jun Feng
- Key State Laboratory of Drug Innovation and Pharmaceutical Technology, China State Institute of Pharmaceutical Industry, Shanghai, China.,Department of Peptide Drugs R&D, Shanghai Duomirui Biotechnology Co., Ltd., Shanghai, China
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14
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15
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Chemokine CCL28 Is a Potent Therapeutic Agent for Oropharyngeal Candidiasis. Antimicrob Agents Chemother 2020; 64:AAC.00210-20. [PMID: 32423961 DOI: 10.1128/aac.00210-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 05/15/2020] [Indexed: 12/28/2022] Open
Abstract
Candida albicans is a commensal organism that causes life-threatening or life-altering opportunistic infections. Treatment of Candida infections is limited by the paucity of antifungal drug classes. Naturally occurring antimicrobial peptides are promising agents for drug development. CCL28 is a CC chemokine that is abundant in saliva and has in vitro antimicrobial activity. In this study, we examine the in vivo Candida killing capacity of CCL28 in oropharyngeal candidiasis as well as the spectrum and mechanism of anti-Candida activity. In the mouse model of oropharyngeal candidiasis, application of wild-type CCL28 reduces oral fungal burden in severely immunodeficient mice without causing excessive inflammation or altering tissue neutrophil recruitment. CCL28 is effective against multiple clinical strains of C. albicans Polyamine protein transporters are not required for CCL28 anti-Candida activity. Both structured and unstructured CCL28 proteins show rapid and sustained fungicidal activity that is superior to that of clinical antifungal agents. Application of wild-type CCL28 to C. albicans results in membrane disruption as measured by solute movement, enzyme leakage, and induction of negative Gaussian curvature on model membranes. Membrane disruption is reduced in CCL28 lacking the functional C-terminal tail. Our results strongly suggest that CCL28 can exert antifungal activity in part via membrane permeation and has potential for development as an anti-Candida therapeutic agent without inflammatory side effects.
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16
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Lamp J, Ikonomova SP, Karlsson AJ, Xia Q, Wang Y. Online capillary electrophoresis - mass spectrometry analysis of histatin-5 and its degradation products. Analyst 2020; 145:4787-4794. [PMID: 32555825 PMCID: PMC7391080 DOI: 10.1039/d0an00756k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Histatin-5 (Hst-5) is a human salivary peptide with antibacterial and antifungal activities. Thorough characterization and reliable quantification of Hst-5 and its degradation products are essential for understanding the Hst-5 degradation pathway. Due to the highly basic and strong cationic nature of the Hst-5 peptide, the quantitative analysis of Hst-5 and its degradation forms by online mass spectrometry remains challenging. Here, we adopt a recently developed electrokinetically pumped sheath liquid capillary electrophoresis - mass spectrometry (CE-MS) coupling technology, and successfully apply it for the analysis of Hst-5 and its degradation products. Our CE-MS method is demonstrated to be robust and quantitative. This novel analytical platform is reproducible and free of sample carryover. The efficacy of this method is demonstrated with a kinetic study of Hst-5 degradation by Sap9, a secreted aspartic peptidase. Our work demonstrates the potential of online CE-MS as a powerful approach for characterizing highly basic peptides.
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Affiliation(s)
- Jared Lamp
- CMP Scientific, Corp., 760 Parkside Ave, STE 211, Brooklyn, NY 11226, USA
| | - Svetlana P Ikonomova
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD, USA
| | - Amy J Karlsson
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD, USA
| | - Qiangwei Xia
- CMP Scientific, Corp., 760 Parkside Ave, STE 211, Brooklyn, NY 11226, USA
| | - Yan Wang
- Proteomics Core Facility, University of Maryland, College Park, MD, USA. and NIH/NIDCR, Bldg 30, Rm 320, 30 Convent Drive, Bethesda, MD 20892-4370, USA
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17
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Specific metallo-protein interactions and antimicrobial activity in Histatin-5, an intrinsically disordered salivary peptide. Sci Rep 2019; 9:17303. [PMID: 31754129 PMCID: PMC6872563 DOI: 10.1038/s41598-019-52676-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 10/10/2019] [Indexed: 02/06/2023] Open
Abstract
Histatin-5 (Hst-5) is an antimicrobial, salivary protein that is involved in the host defense system. Hst-5 has been proposed to bind functionally relevant zinc and copper but presents challenges in structural studies due to its disordered conformation in aqueous solution. Here, we used circular dichroism (CD) and UV resonance Raman (UVRR) spectroscopy to define metallo-Hst-5 interactions in aqueous solution. A zinc-containing Hst-5 sample exhibits shifted Raman bands, relative to bands observed in the absence of zinc. Based on comparison to model compounds and to a family of designed, zinc-binding beta hairpins, the alterations in the Hst-5 UVRR spectrum are attributed to zinc coordination by imidazole side chains. Zinc addition also shifted a tyrosine aromatic ring UVRR band through an electrostatic interaction. Copper addition did not have these effects. A sequence variant, H18A/H19A, was employed; this mutant has less potent antifungal activity, when compared to Hst-5. Zinc addition had only a small effect on the thermal stability of this mutant. Interestingly, both zinc and copper addition shifted histidine UVRR bands in a manner diagnostic for metal coordination. Results obtained with a K13E/R22G mutant were similar to those obtained with wildtype. These experiments show that H18 and H19 contribute to a zinc binding site. In the H18A/H19A mutant the specificity of the copper/zinc binding sites is lost. The experiments implicate specific zinc binding to be important in the antimicrobial activity of Hst-5.
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18
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Ikonomova SP, Moghaddam-Taaheri P, Wang Y, Doolin MT, Stroka KM, Hube B, Karlsson AJ. Effects of histatin 5 modifications on antifungal activity and kinetics of proteolysis. Protein Sci 2019; 29:480-493. [PMID: 31675138 DOI: 10.1002/pro.3767] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 10/07/2019] [Accepted: 10/28/2019] [Indexed: 12/31/2022]
Abstract
Histatin 5 (Hst-5) is an antimicrobial peptide with strong antifungal activity against Candida albicans, an opportunistic pathogen that is a common cause of oral thrush. The peptide is natively secreted by human salivary glands and shows promise as an alternative therapeutic against infections caused by C. albicans. However, Hst-5 can be cleaved and inactivated by a family of secreted aspartic proteases (Saps) produced by C. albicans. Single-residue substitutions can significantly affect the proteolytic resistance of Hst-5 to Saps and its antifungal activity; the K17R substitution increases resistance to proteolysis, while the K11R substitution enhances antifungal activity. In this work, we showed that the positive effects of these two single-residue modifications can be combined in a single peptide, K11R-K17R, with improved proteolytic resistance and antifungal activity. We also investigated the effect of additional single-residue substitutions, with a focus on the effect of addition or removal of negatively charged residues, and found Sap-dependent effects on degradation. Both single- and double-substitutions affected the kinetics of proteolytic degradation of the intact peptide and of the fragments formed during degradation. Our results demonstrate the importance of considering proteolytic stability and not just antimicrobial activity when designing peptides for potential therapeutic applications.
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Affiliation(s)
- Svetlana P Ikonomova
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland
| | | | - Yan Wang
- Proteomics Core, University of Maryland, College Park, Maryland
| | - Mary T Doolin
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland
| | - Kimberly M Stroka
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Hans Knöll Institute, Jena, Germany.,Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Amy J Karlsson
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland.,Fischell Department of Bioengineering, University of Maryland, College Park, Maryland
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19
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Brown JW, Badahdah A, Iticovici M, Vickers TJ, Alvarado DM, Helmerhorst EJ, Oppenheim FG, Mills JC, Ciorba MA, Fleckenstein JM, Bullitt E. A Role for Salivary Peptides in the Innate Defense Against Enterotoxigenic Escherichia coli. J Infect Dis 2019. [PMID: 29528423 DOI: 10.1093/infdis/jiy032] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Background Diarrheal disease from enterotoxigenic Escherichia coli (ETEC) causes significant worldwide morbidity and mortality in young children residing in endemic countries and is the leading cause of traveler's diarrhea. As ETEC enters the body through the oral cavity and cotransits the digestive tract with salivary components, we hypothesized that the antimicrobial activity of salivary proteins might extend beyond the oropharynx into the proximal digestive tract. Results Here, we show that the salivary peptide histatin-5 binds colonization factor antigen I pili, thereby blocking adhesion of ETEC to intestinal epithelial cells. Mechanistically, we demonstrate that histatin-5 stiffens the typically dynamic pili, abolishing their ability to function as spring-like shock absorbers, thereby inhibiting colonization within the turbulent vortices of chyme in the gastrointestinal tract. Conclusions Our data represent the first report of a salivary component exerting specific antimicrobial activity against an enteric pathogen and suggest that histatin-5 and related peptides might be exploited for prophylactic and/or therapeutic uses. Numerous viruses, bacteria, and fungi traverse the oropharynx to cause disease, so there is considerable opportunity for various salivary components to neutralize these pathogens prior to arrival at their target organ. Identification of additional salivary components with unexpectedly broad antimicrobial spectra should be a priority.
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Affiliation(s)
- Jeffrey W Brown
- Department of Physiology and Biophysics, Boston University School of Medicine, Massachusetts.,Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
| | - Arwa Badahdah
- Department of Periodontology and Oral Biology, Boston University Goldman School of Dental Medicine, Massachusetts
| | - Micah Iticovici
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
| | - Tim J Vickers
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
| | - David M Alvarado
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
| | - Eva J Helmerhorst
- Department of Molecular and Cell Biology, Boston University, Massachusetts
| | - Frank G Oppenheim
- Department of Molecular and Cell Biology, Boston University, Massachusetts.,Department of Biochemistry, Henry M. Goldman School of Dental Medicine, Boston University, Massachusetts
| | - Jason C Mills
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri.,Department of Developmental Biology, Washington University School of Medicine, St Louis, Missouri.,Department of Pathology and Immunology, Washington University School of Medicine, St Louis, Missouri
| | - Matthew A Ciorba
- Division of Gastroenterology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
| | - James M Fleckenstein
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri.,Department of Molecular Microbiology and Microbial Pathogenesis Program, Washington University School of Medicine, St Louis, Missouri.,Department of USA Medicine Service, Veterans Affairs Medical Center, St Louis, Missouri
| | - Esther Bullitt
- Department of Physiology and Biophysics, Boston University School of Medicine, Massachusetts
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20
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Jephthah S, Staby L, Kragelund BB, Skepö M. Temperature Dependence of Intrinsically Disordered Proteins in Simulations: What are We Missing? J Chem Theory Comput 2019; 15:2672-2683. [DOI: 10.1021/acs.jctc.8b01281] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- S. Jephthah
- Division of Theoretical Chemistry, Lund University, 221 00 Lund, Sweden
| | - L. Staby
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - B. B. Kragelund
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - M. Skepö
- Division of Theoretical Chemistry, Lund University, 221 00 Lund, Sweden
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21
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New developments in force fields for biomolecular simulations. Curr Opin Struct Biol 2018; 49:129-138. [DOI: 10.1016/j.sbi.2018.02.002] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 01/30/2018] [Accepted: 02/04/2018] [Indexed: 11/18/2022]
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22
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The Effects of Antimicrobial Peptide Nal-P-113 on Inhibiting Periodontal Pathogens and Improving Periodontal Status. BIOMED RESEARCH INTERNATIONAL 2018; 2018:1805793. [PMID: 29736391 PMCID: PMC5875022 DOI: 10.1155/2018/1805793] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 12/31/2017] [Indexed: 12/31/2022]
Abstract
Periodontal disease consists of chronic gingival inflammation characterized by both degradation of the periodontal connective tissue and alveolar bone loss. Drug therapy is used as an auxiliary treatment method in severe chronic periodontitis, aggressive periodontitis, and periodontitis-associated systemic disease. Nal-P-113, a modified antimicrobial peptide, specifically replaces the histidine residues of P-113 with the bulky amino acid β-naphthylalanine, and our previous studies have verified that this novel peptide is not toxic to the human body within a certain concentration range. The objective of the present study was to evaluate the effect of Nal-P-113 on periodontal pathogens and periodontal status in clinical studies. In a split-mouth clinical trial, the pocket depth and bleeding index values tended to decrease in the experimental group compared with those in the control group. SEM results verified that Nal-P-113 restrained the maturation of plaque. Based on real-time polymerase chain reaction, the levels of Fusobacterium nucleatum, Streptococcus gordonii, Treponema denticola, and Porphyromonas gingivalis in subgingival plaque were decreased when the subjects were given Nal-P-113. Bacterial growth curve analysis and a biofilm susceptibility assay verified that Nal-P-113 at a concentration of 20 μg/mL restrained the growth of S. gordonii, F. nucleatum, and P. gingivalis and biofilm formation. Therefore, Nal-P-113 effectively reduces periodontal pathogens and ameliorates periodontal status.
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23
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Łoboda D, Kozłowski H, Rowińska-Żyrek M. Antimicrobial peptide–metal ion interactions – a potential way of activity enhancement. NEW J CHEM 2018. [DOI: 10.1039/c7nj04709f] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We discuss the potential correlation between the antimicrobial peptide–metal binding mode, structure, thermodynamics and mode of action.
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Affiliation(s)
- D. Łoboda
- Faculty of Chemistry
- University of Wroclaw
- 50-383 Wroclaw
- Poland
| | - H. Kozłowski
- Public Higher Medical Professional School in Opole
- 45-060 Opole
- Poland
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24
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Ikonomova SP, Moghaddam-Taaheri P, Jabra-Rizk MA, Wang Y, Karlsson AJ. Engineering improved variants of the antifungal peptide histatin 5 with reduced susceptibility to Candida albicans secreted aspartic proteases and enhanced antimicrobial potency. FEBS J 2017; 285:146-159. [PMID: 29143452 DOI: 10.1111/febs.14327] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 10/06/2017] [Accepted: 11/09/2017] [Indexed: 12/20/2022]
Abstract
Candida albicans is an opportunistic fungal pathogen and a commensal organism that commonly colonizes mucosal surfaces, including those inside the human mouth. To help control C. albicans, human saliva contains the antifungal peptide histatin 5 (Hst-5), which has strong antifungal activity against C. albicans. However, the pathogen produces secreted aspartic proteases (Saps) that cleave Hst-5 at lysine residues and eliminate its antifungal properties. We designed variants of Hst-5 with its lysine residues substituted with arginine or leucine to evaluate the effect on proteolysis by Saps. We found site-, residue-, and Sap-dependent effects from single amino acid substitutions. The K17R and K17L modifications led to dramatic results, with over 77% and 100% intact peptide remaining after incubation with Sap9 and Sap2, respectively, compared to 47% and 61% of Hst-5. This decrease in proteolysis was accompanied by a reduction in cleavage on the C-terminal side of K17, suggesting the Saps prefer lysine at K17 for cleavage. Incubation with C. albicans cells and culture supernatant corroborated the results with purified Saps and highlighted their biological relevance. The modifications to Hst-5 do not diminish the antifungal activity of Hst-5, and, in fact, the K17R, K17L, and K11R peptides retained significantly more antifungal activity after treatment with Saps than Hst-5. Our results indicate that single amino acid modifications drastically impact both proteolysis at the modification sites and the overall level of proteolysis of the peptide, demonstrating the potential of designing peptides for resistance to proteolysis as a means for improving therapeutic efficacy.
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Affiliation(s)
- Svetlana P Ikonomova
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD, USA
| | | | - Mary Ann Jabra-Rizk
- Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, MD, USA.,Department of Oncology and Diagnostic Sciences, Dental School, University of Maryland, Baltimore, MD, USA
| | - Yan Wang
- Proteomics Core Facility, College of Mathematics and Natural Sciences, University of Maryland, College Park, MD, USA
| | - Amy J Karlsson
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD, USA.,Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
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25
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Kulstein G, Wiegand P. Comprehensive examination of conventional and innovative body fluid identification approaches and DNA profiling of laundered blood- and saliva-stained pieces of cloths. Int J Legal Med 2017; 132:67-81. [DOI: 10.1007/s00414-017-1691-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 09/12/2017] [Indexed: 01/26/2023]
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26
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Conklin SE, Bridgman EC, Su Q, Riggs-Gelasco P, Haas KL, Franz KJ. Specific Histidine Residues Confer Histatin Peptides with Copper-Dependent Activity against Candida albicans. Biochemistry 2017; 56:4244-4255. [PMID: 28763199 DOI: 10.1021/acs.biochem.7b00348] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The histidine-rich salivary peptides of the histatin family are known to bind copper (Cu) and other metal ions in vitro; however, the details of these interactions are poorly understood, and their implications for in vivo antifungal activity have not been established. Here, we show that the availability of Cu during exposure of Candida albicans to histatin-5 (Hist-5) modulates its antifungal activity. Antifungal susceptibility testing revealed that co-treatment of Hist-5 with Cu improved the EC50 from ∼5 to ∼1 μM, whereas co-treatment with a high-affinity Cu-specific chelator abrogated antifungal activity. Spectrophotometric titrations revealed two previously unrecognized Cu(I)-binding sites with apparent Kd values at pH 7.4, ∼20 nM, and confirmed a high-affinity Cu(II)-binding site at the Hist-5 N-terminus with an apparent Kd of ∼8 pM. Evaluation of a series of His-to-Ala full-length and truncated Hist-5 peptides identified adjacent His residues (bis-His) as critical anchors for Cu(I) binding, with the presence of a third ligand revealed by X-ray absorption spectroscopy. On their own, the truncated peptides were ineffective at inhibiting the growth of C. albicans, but treatment with supplemental Cu resulted in EC50 values down to ∼5 μM, approaching that of full-length Hist-5. The efficacy of the peptides depended on an intact bis-His site and correlated with Cu(I) affinity. Together, these results establish new structure-function relationships linking specific histidine residues with Cu binding affinity and antifungal activity and provide further evidence of the involvement of metals in modulating the biological activity of these antifungal peptides.
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Affiliation(s)
- Steven E Conklin
- Department of Chemistry, Duke University , Durham, North Carolina 27708, United States
| | - Emma C Bridgman
- Department of Chemistry & Physics, Saint Mary's College , Notre Dame, Indiana 46556, United States
| | - Qiang Su
- Department of Chemistry, Duke University , Durham, North Carolina 27708, United States
| | - Pamela Riggs-Gelasco
- Department of Chemistry and Biochemistry, College of Charleston , Charleston, South Carolina 29424, United States
| | - Kathryn L Haas
- Department of Chemistry & Physics, Saint Mary's College , Notre Dame, Indiana 46556, United States
| | - Katherine J Franz
- Department of Chemistry, Duke University , Durham, North Carolina 27708, United States
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27
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Sharma KK, Maurya IK, Khan SI, Jacob MR, Kumar V, Tikoo K, Jain R. Discovery of a Membrane-Active, Ring-Modified Histidine Containing Ultrashort Amphiphilic Peptide That Exhibits Potent Inhibition of Cryptococcus neoformans. J Med Chem 2017; 60:6607-6621. [DOI: 10.1021/acs.jmedchem.7b00481] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Krishna K. Sharma
- Department
of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Indresh Kumar Maurya
- Department
of Microbial Biotechnology, Panjab University, Sector 25, Chandigarh, 160 014, India
| | - Shabana I. Khan
- National
Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Melissa R. Jacob
- National
Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Vinod Kumar
- Department
of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Kulbhushan Tikoo
- Department
of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Rahul Jain
- Department
of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
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28
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Henderson JM, Waring AJ, Separovic F, Lee KYC. Antimicrobial Peptides Share a Common Interaction Driven by Membrane Line Tension Reduction. Biophys J 2017; 111:2176-2189. [PMID: 27851941 DOI: 10.1016/j.bpj.2016.10.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 09/30/2016] [Accepted: 10/05/2016] [Indexed: 12/30/2022] Open
Abstract
Antimicrobial peptides (AMPs) are a class of host-defense molecules that neutralize a broad range of pathogens. Their membrane-permeabilizing behavior has been commonly attributed to the formation of pores; however, with the continuing discovery of AMPs, many are uncharacterized and their exact mechanism remains unknown. Using atomic force microscopy, we previously characterized the disruption of model membranes by protegrin-1 (PG-1), a cationic AMP from pig leukocytes. When incubated with zwitterionic membranes of dimyristoylphosphocholine, PG-1 first induced edge instability at low concentrations, then porous defects at intermediate concentrations, and finally worm-like micelle structures at high concentrations. These rich structural changes suggested that pore formation constitutes only an intermediate state along the route of PG-1's membrane disruption process. The formation of these structures could be best understood by using a mesophase framework of a binary mixture of lipids and peptides, where PG-1 acts as a line-active agent in lowering interfacial bilayer tensions. We have proposed that rather than being static pore formers, AMPs share a common ability to lower interfacial tensions that promote membrane transformations. In a study of 13 different AMPs, we found that peptide line-active behavior was not driven by the overall charge, and instead was correlated with their adoption of imperfect secondary structures. These peptide structures commonly positioned charged residues near the membrane interface to promote deformation favorable for their incorporation into the membrane. Uniquely, the data showed that barrel-stave-forming peptides such as alamethicin are not line-active, and that the seemingly disparate models of toroidal pores and carpet activity are actually related. We speculate that this interplay between peptide structure and the distribution of polar residues in relation to the membrane governs AMP line activity in general and represents a novel, to our knowledge, avenue for the rational design of new drugs.
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Affiliation(s)
- J Michael Henderson
- Department of Chemistry, The University of Chicago, Chicago, Illinois; Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois; The James Frank Institute, The University of Chicago, Chicago, Illinois
| | - Alan J Waring
- Los Angeles Biomedical Research Institute, Harbor-UCLA Medical Center, Torrance, California; Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, Victoria, Australia
| | - Ka Yee C Lee
- Department of Chemistry, The University of Chicago, Chicago, Illinois; Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois; The James Frank Institute, The University of Chicago, Chicago, Illinois.
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29
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Jephthah S, Henriques J, Cragnell C, Puri S, Edgerton M, Skepö M. Structural Characterization of Histatin 5-Spermidine Conjugates: A Combined Experimental and Theoretical Study. J Chem Inf Model 2017; 57:1330-1341. [PMID: 28586222 DOI: 10.1021/acs.jcim.7b00150] [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
Histatin 5 (Hst5) is a naturally occurring antimicrobial peptide that acts as the first line of defense against oral candidiasis. It has been shown that conjugation of the active Hst5 fragment, Hst54-15, and the polyamine spermidine (Spd) improves the candidacidal effect. Knowledge about the structure of these conjugates is, however, very limited. Thus, the aim of this study was to characterize the structural properties of the Hst54-15-Spd conjugates by performing atomistic molecular dynamics simulations in combination with small-angle X-ray scattering. It was shown that the Hst54-15-Spd conjugates adopt extended and slightly rigid random coil conformations without any secondary structure in aqueous solution. It is hypothesized that the increased fungal killing potential of Hst54-15-Spd, in comparison with the Spd-Hst54-15 conjugate, is due to the more extended conformations of the former, which cause the bonded Spd molecule to be more accessible for recognition by polyamine transporters in the cell.
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Affiliation(s)
- Stephanie Jephthah
- Division of Theoretical Chemistry, Lund University , Post Office Box 124, S-221 00 Lund, Sweden
| | - João Henriques
- Division of Theoretical Chemistry, Lund University , Post Office Box 124, S-221 00 Lund, Sweden
| | - Carolina Cragnell
- Division of Theoretical Chemistry, Lund University , Post Office Box 124, S-221 00 Lund, Sweden
| | - Sumant Puri
- Pediatrics and Community Oral Health Sciences, Temple University , Philadelphia, Pennsylvania 19147, United States
| | - Mira Edgerton
- Department of Oral Biology, University at Buffalo , Buffalo, New York 14214-3092, United States
| | - Marie Skepö
- Division of Theoretical Chemistry, Lund University , Post Office Box 124, S-221 00 Lund, Sweden
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30
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Basiri T, Johnson N, Moffa E, Mulyar Y, Serra Nunes P, Machado M, Siqueira W. Duplicated or Hybridized Peptide Functional Domains Promote Oral Homeostasis. J Dent Res 2017; 96:1162-1167. [DOI: 10.1177/0022034517708552] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- T. Basiri
- School of Dentistry and Department of Biochemistry, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON, Canada
| | - N.D. Johnson
- School of Dentistry and Department of Biochemistry, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON, Canada
| | - E.B. Moffa
- School of Dentistry and Department of Biochemistry, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON, Canada
- Department of Pediatric Dentistry, Orthodontics and Public Health, Bauru Dental School, University of São Paulo, Bauru, Brazil
- CEUMA University, Post-Graduate Program in Dentistry, Maranhão, Brazil
| | - Y. Mulyar
- School of Dentistry and Department of Biochemistry, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON, Canada
| | - P.L. Serra Nunes
- CEUMA University, Post-Graduate Program in Dentistry, Maranhão, Brazil
| | - M.A.A.M. Machado
- Department of Pediatric Dentistry, Orthodontics and Public Health, Bauru Dental School, University of São Paulo, Bauru, Brazil
| | - W.L. Siqueira
- School of Dentistry and Department of Biochemistry, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON, Canada
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31
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Adsorption of polyelectrolyte-like proteins to silica surfaces and the impact of pH on the response to ionic strength. A Monte Carlo simulation and ellipsometry study. J Colloid Interface Sci 2017; 494:266-273. [DOI: 10.1016/j.jcis.2017.01.087] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 01/18/2017] [Accepted: 01/19/2017] [Indexed: 11/17/2022]
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Bastos P, Trindade F, da Costa J, Ferreira R, Vitorino R. Human Antimicrobial Peptides in Bodily Fluids: Current Knowledge and Therapeutic Perspectives in the Postantibiotic Era. Med Res Rev 2017; 38:101-146. [PMID: 28094448 PMCID: PMC7168463 DOI: 10.1002/med.21435] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 11/04/2016] [Accepted: 11/14/2016] [Indexed: 12/12/2022]
Abstract
Antimicrobial peptides (AMPs) are an integral part of the innate immune defense mechanism of many organisms. Due to the alarming increase of resistance to antimicrobial therapeutics, a growing interest in alternative antimicrobial agents has led to the exploitation of AMPs, both synthetic and isolated from natural sources. Thus, many peptide-based drugs have been the focus of increasing attention by many researchers not only in identifying novel AMPs, but in defining mechanisms of antimicrobial peptide activity as well. Herein, we review the available strategies for the identification of AMPs in human body fluids and their mechanism(s) of action. In addition, an overview of the distribution of AMPs across different human body fluids is provided, as well as its relation with microorganisms and infectious conditions.
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Affiliation(s)
- Paulo Bastos
- Department of Medical Sciences, iBiMED-Institute for Research in Biomedicine, University of Aveiro, Aveiro, Portugal
| | - Fábio Trindade
- Department of Medical Sciences, iBiMED-Institute for Research in Biomedicine, University of Aveiro, Aveiro, Portugal.,Unidade de Investigação Cardiovascular, Departamento de Cirurgia e Fisiologia, Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - João da Costa
- Department of Chemistry, CESAM, University of Aveiro, Aveiro, Portugal
| | - Rita Ferreira
- Department of Chemistry, QOPNA, Mass Spectrometry Center, University of Aveiro, Aveiro, Portugal
| | - Rui Vitorino
- Department of Medical Sciences, iBiMED-Institute for Research in Biomedicine, University of Aveiro, Aveiro, Portugal.,Unidade de Investigação Cardiovascular, Departamento de Cirurgia e Fisiologia, Faculdade de Medicina, Universidade do Porto, Porto, Portugal
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Abstract
The proteome of whole saliva, in contrast to that of serum, is highly susceptible to a variety of physiological and biochemical processes. First, salivary protein secretion is under neurologic control, with protein output being dependent on the stimulus. Second, extensive salivary protein modifications occur in the oral environment, where a plethora of host- and bacteria-derived enzymes act on proteins emanating from the glandular ducts. Salivary protein biosynthesis starts with the transcription and translation of salivary protein genes in the glands, followed by post-translational processing involving protein glycosylation, phosphorylation, and proteolysis. This gives rise to salivary proteins occurring in families, consisting of structurally closely related family members. Once glandular secretions enter the non-sterile oral environment, proteins are subjected to additional and continuous protein modifications, leading to extensive proteolytic cleavage, partial deglycosylation, and protein-protein complex formation. All these protein modifications occur in a dynamic environment dictated by the continuous supply of newly synthesized proteins and removal by swallowing. Understanding the proteome of whole saliva in an environment of continuous turnover will be a prerequisite to gain insight into the physiological and pathological processes relevant to oral health, and be crucial for the identification of meaningful biomarkers for oral disease.
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Affiliation(s)
- E J Helmerhorst
- Boston University Goldman School of Dental Medicine, Department of Periodontology and Oral Biology, 700 Albany Street CABR W-201, Boston, MA 02118, USA.
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Khurshid Z, Naseem M, Sheikh Z, Najeeb S, Shahab S, Zafar MS. Oral antimicrobial peptides: Types and role in the oral cavity. Saudi Pharm J 2016; 24:515-524. [PMID: 27752223 PMCID: PMC5059823 DOI: 10.1016/j.jsps.2015.02.015] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 02/20/2015] [Indexed: 12/27/2022] Open
Abstract
Antimicrobial peptides (AMPs) are a wide-ranging class of host-defense molecules that act early to contest against microbial invasion and challenge. These are small cationic peptides that play an important in the development of innate immunity. In the oral cavity, the AMPs are produced by the salivary glands and the oral epithelium and serve defensive purposes. The aim of this review was to discuss the types and functions of oral AMPs and their role in combating microorganisms and infections in the oral cavity.
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Affiliation(s)
- Zohaib Khurshid
- School of Materials and Metallurgy, University of Birmingham, United Kingdom
| | - Mustafa Naseem
- Department of Community Dentistry and Preventive Dentistry, School of Dentistry, Ziauddin University, Pakistan
| | - Zeeshan Sheikh
- Faculty of Dentistry, University of Toronto, Toronto, Canada
| | - Shariq Najeeb
- School of Dentistry, Al-Farabi Dental College, Saudi Arabia
| | - Sana Shahab
- Department of Dental Materials Science, Sir Syed College of Medical Sciences for Girls, Pakistan
| | - Muhammad Sohail Zafar
- Department of Restorative Dentistry, College of Dentistry, Taibah University, Madinah Al-Munawwarah, Saudi Arabia
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Khurshid Z, Najeeb S, Mali M, Moin SF, Raza SQ, Zohaib S, Sefat F, Zafar MS. Histatin peptides: Pharmacological functions and their applications in dentistry. Saudi Pharm J 2016; 25:25-31. [PMID: 28223859 PMCID: PMC5310145 DOI: 10.1016/j.jsps.2016.04.027] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 04/26/2016] [Indexed: 01/10/2023] Open
Abstract
There are many human oral antimicrobial peptides responsible for playing important roles including maintenance, repairing of oral tissues (hard or soft) and defense against oral microbes. In this review we have highlighted the biochemistry, physiology and proteomics of human oral histatin peptides, secreted from parotid and submandibular salivary glands in human. The significance of these peptides includes capability for ionic binding that can kill fungal Candida albicans. They have histidine rich amino acid sequences (7-12 family members; corresponding to residues 12-24, 13-24, 12-25, 13-25, 5-11, and 5-12, respectively) for Histatin-3. However, Histatin-3 can be synthesized proteolytically from histatin 5 or 6. Due to their fungicidal response and high biocompatibility (little or no toxicity), these peptides can be considered as therapeutic agents with most probable applications for example, artificial saliva for denture wearers and salivary gland dysfunction conditions. The objectives of current article are to explore the human histatin peptides for its types, chemical and biological aspects. In addition, the potential for therapeutic bio-dental applications has been elaborated.
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Affiliation(s)
- Zohaib Khurshid
- Department of Dental Biomaterials, College of Dentistry, King Faisal University, Al-Ahsa, Saudi Arabia
| | - Shariq Najeeb
- School of Dentistry, University of Sheffield, Sheffield, UK
| | - Maria Mali
- Department of Endodontics, Fatima Jinnah Dental College, Karachi, Pakistan
| | - Syed Faraz Moin
- National Centre for Proteomics, Karachi University, Pakistan
| | - Syed Qasim Raza
- Institute of Research and Consulting, King Faisal University, Al-Hofuf, Saudi Arabia
| | - Sana Zohaib
- Department of Biomedical Engineering, King Faisal University, Al-Hofuf, Saudi Arabia
| | - Farshid Sefat
- Department of Biomedical Engineering, King Faisal University, Al-Hofuf, Saudi Arabia; Department of Medical Engineering, University of Bradford, Bradford, UK
| | - Muhammad Sohail Zafar
- Department of Restorative Dentistry, College of Dentistry, Taibah University, Al Madinah Al Munawwarah, Saudi Arabia
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Hyltegren K, Nylander T, Lund M, Skepö M. Adsorption of the intrinsically disordered saliva protein histatin 5 to silica surfaces. A Monte Carlo simulation and ellipsometry study. J Colloid Interface Sci 2016; 467:280-290. [DOI: 10.1016/j.jcis.2016.01.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 01/11/2016] [Accepted: 01/13/2016] [Indexed: 11/26/2022]
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Cragnell C, Durand D, Cabane B, Skepö M. Coarse-grained modeling of the intrinsically disordered protein Histatin 5 in solution: Monte Carlo simulations in combination with SAXS. Proteins 2016; 84:777-91. [PMID: 26914439 DOI: 10.1002/prot.25025] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 02/17/2016] [Accepted: 02/18/2016] [Indexed: 01/24/2023]
Abstract
Monte Carlo simulations and coarse-grained modeling have been used to analyze Histatin 5, an unstructured short cationic salivary peptide known to have anticandidical properties. The calculated scattering functions have been compared with intensity curves and the distance distribution function P(r) obtained from small angle X-ray scattering (SAXS), at both high and low salt concentrations. The aim was to achieve a molecular understanding and a physico-chemical insight of the obtained SAXS results and to gain information of the conformational changes of Histatin 5 due to altering salt content, charge distribution, and net charge. From a modeling perspective, the accuracy of the electrostatic interactions are of special interest. The used coarse-grained model was based on the primitive model in which charged hard spheres differing in charge and in size represent the ionic particles, and the solvent only enters the model through its relative permittivity. The Hamiltonian of the model comprises three different contributions: (i) excluded volumes, (ii) electrostatic, and (iii) van der Waals interactions. Even though the model can be considered as gross omitting all atomistic details, a great correspondence is obtained with the experimental results. Proteins 2016; 84:777-791. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Carolina Cragnell
- Chemical Department, Theoretical Chemistry, Lund University, Lund, Sweden
| | | | - Bernard Cabane
- PMMH, CNRS UMR 7636, ESPCI, Paris Cedex 05, F-75231, France
| | - Marie Skepö
- Chemical Department, Theoretical Chemistry, Lund University, Lund, Sweden
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38
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Antifungal Activity and Action Mechanism of Histatin 5-Halocidin Hybrid Peptides against Candida ssp. PLoS One 2016; 11:e0150196. [PMID: 26918792 PMCID: PMC4769088 DOI: 10.1371/journal.pone.0150196] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 02/10/2016] [Indexed: 11/19/2022] Open
Abstract
The candidacidal activity of histatin 5 is initiated through cell wall binding, followed by translocation and intracellular targeting, while the halocidin peptide exerts its activity by attacking the Candida cell membrane. To improve antimicrobial activities and to understand the killing mechanism of two peptides, six hybrid peptides were designed by conjugating histatin 5 and halocidin. A comparative approach was established to study the activity, salt tolerance, cell wall glucan binding assay, cytotoxicity, generation of ROS and killing kinetics. CD spectrometry was conducted to evaluate secondary structures of these hybrid peptides. Furthermore the cellular localization of hybrid peptides was investigated by confocal fluorescence microscopy. Of the six hybrid congeners, di-PH2, di-WP2 and HHP1 had stronger activities than other hybrid peptides against all tested Candida strains. The MIC values of these peptides were 1–2, 2–4 and 2–4 μg/ml, respectively. Moreover, none of the hybrid peptides was cytotoxic in the hemolytic assay and cell-based cytotoxicity assay. Confocal laser microscopy showed that di-PH2 and HHP1 were translocated into cytoplasm whereas di-WP2 was accumulated on surface of C. albicans to exert their candidacidal activity. All translocated peptides (Hst 5, P113, di-PH2) were capable of generating intracellular ROS except HHP1. Additionally, the KFH residues at C-terminal end of these peptides were assumed for core sequence for active translocation.
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39
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Past, Present, and Future of Antifungal Drug Development. TOPICS IN MEDICINAL CHEMISTRY 2016. [DOI: 10.1007/7355_2016_4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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40
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In Vitro Identification of Histatin 5 Salivary Complexes. PLoS One 2015; 10:e0142517. [PMID: 26544073 PMCID: PMC4636238 DOI: 10.1371/journal.pone.0142517] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 10/22/2015] [Indexed: 01/20/2023] Open
Abstract
With recent progress in the analysis of the salivary proteome, the number of salivary proteins identified has increased dramatically. However, the physiological functions of many of the newly discovered proteins remain unclear. Closely related to the study of a protein’s function is the identification of its interaction partners. Although in saliva some proteins may act primarily as single monomeric units, a significant percentage of all salivary proteins, if not the majority, appear to act in complexes with partners to execute their diverse functions. Coimmunoprecipitation (Co-IP) and pull-down assays were used to identify the heterotypic complexes between histatin 5, a potent natural antifungal protein, and other salivary proteins in saliva. Classical protein–protein interaction methods in combination with high-throughput mass spectrometric techniques were carried out. Co-IP using protein G magnetic Sepharose TM beads suspension was able to capture salivary complexes formed between histatin 5 and its salivary protein partners. Pull-down assay was used to confirm histatin 5 protein partners. A total of 52 different proteins were identified to interact with histatin 5. The present study used proteomic approaches in conjunction with classical biochemical methods to investigate protein–protein interaction in human saliva. Our study demonstrated that when histatin 5 is complexed with salivary amylase, one of the 52 proteins identified as a histatin 5 partner, the antifungal activity of histatin 5 is reduced. We expected that our proteomic approach could serve as a basis for future studies on the mechanism and structural-characterization of those salivary protein interactions to understand their clinical significance.
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41
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Moffa EB, Mussi MCM, Xiao Y, Garrido SS, Machado MAAM, Giampaolo ET, Siqueira WL. Histatin 5 inhibits adhesion of C. albicans to Reconstructed Human Oral Epithelium. Front Microbiol 2015; 6:885. [PMID: 26379655 PMCID: PMC4551819 DOI: 10.3389/fmicb.2015.00885] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 08/12/2015] [Indexed: 11/30/2022] Open
Abstract
Candida albicans is the most pathogenic fungal species, commonly colonizing on human mucosal surfaces. As a polymorphic species, C. albicans is capable of switching between yeast and hyphal forms, causing an array of mucosal and disseminated infections with high mortality. While the yeast form is most commonly associated with systemic disease, the hyphae are more adept at adhering to and penetrating host tissue and are therefore frequently observed in mucosal fungal infections, most commonly oral candidiasis. The formation of a saliva-derived protein pellicle on the mucosa surface can provide protection against C. albicans on oral epithelial cells, and narrow information is available on the mucosal pellicle composition. Histatins are one of the most abundant salivary proteins and presents antifungal and antibacterial activities against many species of the oral microbiota, however, its presence has never been studied in oral mucosa pellicle. The objective of this study was to evaluate the potential of histatin 5 to protect the Human Oral Epithelium against C. albicans adhesion. Human Oral Epithelial Tissues (HOET) were incubated with PBS containing histatin 5 for 2 h, followed by incubation with C. albicans for 1 h at 37°C. The tissues were then washed several times in PBS, transferred to fresh RPMI and incubated for 16 h at 37°C at 5% CO2. HOET were then prepared for histopathological analysis using light microscopy. In addition, the TUNEL assay was employed to evaluate the apoptosis of epithelial cells using fluorescent microscopy. HOET pre-incubated with histatin 5 showed a lower rate of C. albicans growth and cell apoptosis when compared to the control groups (HOET alone and HOET incubated with C. albicans). The data suggest that the coating with histatin 5 is able to reduce C. albicans colonization on epithelial cell surfaces and also protect the basal cell layers from undergoing apoptosis.
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Affiliation(s)
- Eduardo B Moffa
- The University of Western Ontario - Department of Biochemistry and Schulich Dentistry, Schulich School of Medicine and Dentistry, London, ON Canada ; Department of Dental Materials and Prosthodontics, Araraquara Dental School - Universidade Estadual Paulista, São Paulo Brazil
| | - Maria C M Mussi
- The University of Western Ontario - Department of Biochemistry and Schulich Dentistry, Schulich School of Medicine and Dentistry, London, ON Canada ; School of Dentistry, University of São Paulo, São Paulo Brazil
| | - Yizhi Xiao
- The University of Western Ontario - Department of Biochemistry and Schulich Dentistry, Schulich School of Medicine and Dentistry, London, ON Canada
| | - Saulo S Garrido
- Department of Biochemistry and Technological Chemistry - Institute of Chemistry - Universidade Estadual Paulista, São Paulo Brazil
| | - Maria A A M Machado
- Department of Pediatric Dentistry, Orthodontics and Public Health, Bauru Dental School, University of São Paulo, Bauru Brazil
| | - Eunice T Giampaolo
- Department of Dental Materials and Prosthodontics, Araraquara Dental School - Universidade Estadual Paulista, São Paulo Brazil
| | - Walter L Siqueira
- The University of Western Ontario - Department of Biochemistry and Schulich Dentistry, Schulich School of Medicine and Dentistry, London, ON Canada
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42
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Henriques J, Cragnell C, Skepö M. Molecular Dynamics Simulations of Intrinsically Disordered Proteins: Force Field Evaluation and Comparison with Experiment. J Chem Theory Comput 2015; 11:3420-31. [PMID: 26575776 DOI: 10.1021/ct501178z] [Citation(s) in RCA: 181] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
An increasing number of studies using molecular dynamics (MD) simulations of unfolded and intrinsically disordered proteins (IDPs) suggest that current force fields sample conformations that are overly collapsed. Here, we study the applicability of several state-of-the-art MD force fields, of the AMBER and GROMOS variety, for the simulation of Histatin 5, a short (24 residues) cationic salivary IDP with antimicrobial and antifungal properties. The quality of the simulations is assessed in three complementary analyses: (i) protein shape and size comparison with recent experimental small-angle X-ray scattering data; (ii) secondary structure prediction; (iii) energy landscape exploration and conformational class analysis. Our results show that, indeed, standard force fields sample conformations that are too compact, being systematically unable to reproduce experimental evidence such as the scattering function, the shape of the protein as compared with the Kratky plot, and intrapeptide distances obtained through the pair distance distribution function, p(r). The consistency of this deviation suggests that the problem is not mainly due to protein-protein or water-water interactions, whose parametrization varies the most between force fields and water models. In fact, as originally proposed in [ Best et al. J. Chem. Theory Comput. 2014, 10, 5113 - 5124.], balanced protein-water interactions may be the key to solving this problem. Our simulations using this approach produce results in very good agreement with experiment.
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Affiliation(s)
- João Henriques
- Division of Theoretical Chemistry, Lund University , Post Office Box 124, S-221 00 Lund, Sweden
| | - Carolina Cragnell
- Division of Theoretical Chemistry, Lund University , Post Office Box 124, S-221 00 Lund, Sweden
| | - Marie Skepö
- Division of Theoretical Chemistry, Lund University , Post Office Box 124, S-221 00 Lund, Sweden
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43
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Do N, Weindl G, Grohmann L, Salwiczek M, Koksch B, Korting HC, Schäfer-Korting M. Cationic membrane-active peptides - anticancer and antifungal activity as well as penetration into human skin. Exp Dermatol 2014; 23:326-31. [PMID: 24661024 DOI: 10.1111/exd.12384] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2014] [Indexed: 12/28/2022]
Abstract
Cationic antimicrobial peptides are ancient natural broad-spectrum antibiotics, and several compounds also exhibit anticancer activity. However, most applications pertain to bacterial infections, and treatment for skin cancer is less frequently considered. The cytotoxicity of melittin, cecropin A, protegrin-1 and histatin 5 against squamous skin cancer cell lines and normal human keratinocytes was evaluated and compared to established drugs. The results show that melittin clearly outperforms 5-fluorouracil regarding antitumor activity. Importantly, combined melittin and 5-fluorouracil enhanced cytotoxic effects on cancer cells and reduced toxicity on normal keratinocytes. Additionally, minimum inhibitory concentrations indicate that melittin also shows superior activity against clinical and laboratory strains of Candida albicans compared to amphotericin B. To evaluate its potential for topical applications, human skin penetration of melittin was investigated ex vivo and compared to two non-toxic cell-penetrating peptides (CPPs), low molecular weight protamine (LMWP) and penetratin. The stratum corneum prevents penetration into viable epidermis over 6 h; however, the peptides gain access to the viable skin after 24 h. Inhibition of digestive enzymes during skin penetration significantly enhances the availability of intact peptide. In conclusion, melittin may represent an innovative agent for non-melanoma skin cancer and infectious skin diseases. In order to develop a drug candidate, skin absorption and proteolytic digestion by skin enzymes need to be addressed.
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Affiliation(s)
- Nhung Do
- Institute for Pharmacy (Pharmacology and Toxicology), Freie Universität Berlin, Berlin, Germany
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44
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Sikorska E, Kamysz E. Effect of head-to-tail cyclization on conformation of histatin-5. J Pept Sci 2014; 20:952-7. [DOI: 10.1002/psc.2707] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Revised: 09/11/2014] [Accepted: 09/19/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Emilia Sikorska
- Faculty of Chemistry; University of Gdańsk; Wita Stwosza 63 80-308 Gdansk Poland
| | - Elżbieta Kamysz
- Faculty of Chemistry; University of Gdańsk; Wita Stwosza 63 80-308 Gdansk Poland
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45
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Mahindra A, Bagra N, Wangoo N, Jain R, Khan SI, Jacob MR, Jain R. Synthetically modified L-histidine-rich peptidomimetics exhibit potent activity against Cryptococcus neoformans. Bioorg Med Chem Lett 2014; 24:3150-4. [PMID: 24878194 PMCID: PMC4065882 DOI: 10.1016/j.bmcl.2014.04.120] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/01/2014] [Accepted: 04/30/2014] [Indexed: 01/27/2023]
Abstract
We describe the synthesis and antimicrobial evaluation of structurally new peptidomimetics, rich in synthetically modified L-histidine. Two series of tripeptidomimetics were synthesized by varying lipophilicity at the C-2 position of L-histidine and at the N- and C-terminus. The data indicates that peptides (5f, 6f, 9f and 10f) possessing highly lipophilic adamantan-1-yl group displayed strong inhibition of Cryptococcus neoformans. Peptide 6f is the most potent of all with IC50 and MFC values of 0.60 and 0.63 μg/mL, respectively, compared to the commercial drug amphotericin B (IC50=0.69 and MFC=1.25 μg/mL). The selectivity of these peptides to microbial pathogen was examined by a tryptophan fluorescence quenching study and transmission electron microscopy. These studies indicate that the peptides plausibly interact with the mimic membrane of pathogen by direct insertion, and results in disruption of membrane of pathogen.
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Affiliation(s)
- Amit Mahindra
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar, Punjab 160 062, India
| | - Nitin Bagra
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar, Punjab 160 062, India
| | - Nishima Wangoo
- Center for Nanoscience and Nanotechnology, Panjab University, Sector 14, Chandigarh 160 014, India
| | - Rohan Jain
- Center for Nanoscience and Nanotechnology, Panjab University, Sector 14, Chandigarh 160 014, India
| | - Shabana I Khan
- National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, MS 38677, USA
| | - Melissa R Jacob
- National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, MS 38677, USA
| | - Rahul Jain
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar, Punjab 160 062, India.
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46
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How does it kill?: understanding the candidacidal mechanism of salivary histatin 5. EUKARYOTIC CELL 2014; 13:958-64. [PMID: 24951439 DOI: 10.1128/ec.00095-14] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Histatins are salivary cationic peptides that provide the first line of defense against oral candidiasis caused by Candida albicans. This minireview presents a critical evaluation of our knowledge of the candidacidal mechanism of histatin 5 (Hst 5). Hst 5 is the most potent among all histatin family members with regard to its antifungal activity. The mode of action of Hst 5 has been a subject of intense debate. Unlike other classical host innate immune proteins, pore formation or membrane lysis by Hst 5 has largely been disproven, and it is now known that all targets of Hst 5 are intracellular. Hst 5 binds C. albicans cell wall proteins (Ssa1/2) and glycans and is taken up by the cells through fungal polyamine transporters in an energy-dependent manner. Once inside the fungal cells, Hst 5 may affect mitochondrial functions and cause oxidative stress; however, the ultimate cause of cell death is by volume dysregulation and ion imbalance triggered by osmotic stress. Besides these diverse targets, a novel mechanism based on the metal binding abilities of Hst 5 is discussed. Finally, translational approaches for Hst 5, based on peptide design and synergy with other known drugs, are considered a step forward for bench-to-bed application of Hst 5.
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47
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Wang G. Human antimicrobial peptides and proteins. Pharmaceuticals (Basel) 2014; 7:545-94. [PMID: 24828484 PMCID: PMC4035769 DOI: 10.3390/ph7050545] [Citation(s) in RCA: 337] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 04/15/2014] [Accepted: 04/29/2014] [Indexed: 12/11/2022] Open
Abstract
As the key components of innate immunity, human host defense antimicrobial peptides and proteins (AMPs) play a critical role in warding off invading microbial pathogens. In addition, AMPs can possess other biological functions such as apoptosis, wound healing, and immune modulation. This article provides an overview on the identification, activity, 3D structure, and mechanism of action of human AMPs selected from the antimicrobial peptide database. Over 100 such peptides have been identified from a variety of tissues and epithelial surfaces, including skin, eyes, ears, mouths, gut, immune, nervous and urinary systems. These peptides vary from 10 to 150 amino acids with a net charge between -3 and +20 and a hydrophobic content below 60%. The sequence diversity enables human AMPs to adopt various 3D structures and to attack pathogens by different mechanisms. While α-defensin HD-6 can self-assemble on the bacterial surface into nanonets to entangle bacteria, both HNP-1 and β-defensin hBD-3 are able to block cell wall biosynthesis by binding to lipid II. Lysozyme is well-characterized to cleave bacterial cell wall polysaccharides but can also kill bacteria by a non-catalytic mechanism. The two hydrophobic domains in the long amphipathic α-helix of human cathelicidin LL-37 lays the basis for binding and disrupting the curved anionic bacterial membrane surfaces by forming pores or via the carpet model. Furthermore, dermcidin may serve as ion channel by forming a long helix-bundle structure. In addition, the C-type lectin RegIIIα can initially recognize bacterial peptidoglycans followed by pore formation in the membrane. Finally, histatin 5 and GAPDH(2-32) can enter microbial cells to exert their effects. It appears that granulysin enters cells and kills intracellular pathogens with the aid of pore-forming perforin. This arsenal of human defense proteins not only keeps us healthy but also inspires the development of a new generation of personalized medicine to combat drug-resistant superbugs, fungi, viruses, parasites, or cancer. Alternatively, multiple factors (e.g., albumin, arginine, butyrate, calcium, cyclic AMP, isoleucine, short-chain fatty acids, UV B light, vitamin D, and zinc) are able to induce the expression of antimicrobial peptides, opening new avenues to the development of anti-infectious drugs.
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Affiliation(s)
- Guangshun Wang
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, 986495 Nebraska Medical Center, Omaha, NE 68198-6495, USA.
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48
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Mahindra A, Bagra N, Wangoo N, Khan SI, Jacob MR, Jain R. Discovery of Short Peptides Exhibiting High Potency against Cryptococcus neoformans. ACS Med Chem Lett 2014; 5:315-20. [PMID: 24900833 DOI: 10.1021/ml500011v] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 01/15/2014] [Indexed: 01/06/2023] Open
Abstract
Rapid increase in the emergence of resistance against existing antifungal drugs created a need to discover new structural classes of antifungal agents. In this study we describe the synthesis of a new structural class of short antifungal peptidomimetcis, their activity, and plausible mechanism of action. The results of the study show that peptides 11e and 11f are more potent than the control drug amphotericin B, with no cytotoxicity to human cancer cells and noncancerous mammalian kidney cells. The selectivity of peptides to fungus is depicted by transmission electron microscopy studies, and it revealed that 11e possibly disrupts the model membrane of the fungal pathogen.
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Affiliation(s)
- Amit Mahindra
- Department
of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Nitin Bagra
- Department
of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
| | - Nishima Wangoo
- Center
for Nanoscience and Nanotechnology, Panjab University, Sector 14, Chandigarh 160 014, India
| | - Shabana I. Khan
- National
Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Melissa R. Jacob
- National
Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Rahul Jain
- Department
of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Punjab 160 062, India
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49
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Melino S, Santone C, Di Nardo P, Sarkar B. Histatins: salivary peptides with copper(II)- and zinc(II)-binding motifs. FEBS J 2013; 281:657-72. [DOI: 10.1111/febs.12612] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 11/07/2013] [Accepted: 11/11/2013] [Indexed: 02/03/2023]
Affiliation(s)
- Sonia Melino
- Department of Chemical Sciences and Technologies; University of Rome Tor Vergata; Italy
| | - Celeste Santone
- Department of Chemical Sciences and Technologies; University of Rome Tor Vergata; Italy
| | - Paolo Di Nardo
- Department of Medical Sciences and Translational Medicine; University of Rome Tor Vergata; Italy
| | - Bibudhendra Sarkar
- Department of Molecular Structure and Function; The Hospital for Sick Children; University of Toronto; Ontario Canada
- Department of Biochemistry; University of Toronto; Ontario Canada
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50
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Kurut A, Henriques J, Forsman J, Skepö M, Lund M. Role of histidine for charge regulation of unstructured peptides at interfaces and in bulk. Proteins 2013; 82:657-67. [DOI: 10.1002/prot.24445] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 09/12/2013] [Accepted: 09/26/2013] [Indexed: 01/21/2023]
Affiliation(s)
- Anıl Kurut
- Division of Theoretical Chemistry; Lund University; P.O. Box 124 SE-22100 Lund Sweden
| | - João Henriques
- Division of Theoretical Chemistry; Lund University; P.O. Box 124 SE-22100 Lund Sweden
| | - Jan Forsman
- Division of Theoretical Chemistry; Lund University; P.O. Box 124 SE-22100 Lund Sweden
| | - Marie Skepö
- Division of Theoretical Chemistry; Lund University; P.O. Box 124 SE-22100 Lund Sweden
| | - Mikael Lund
- Division of Theoretical Chemistry; Lund University; P.O. Box 124 SE-22100 Lund Sweden
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