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  • 1.
    Berglin, Mattias
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Product Realisation Methodology. University of Gothenburg, Sweden.
    Cavanagh, Jorunn Pauline
    Amicoat A/S, Norway; UiT The Arctic University of Norway, Norway.
    Caous, Josefin Seth
    RISE Research Institutes of Sweden, Materials and Production, Product Realisation Methodology.
    Thakkar, Balmukund Sureshkumar
    Amicoat A/S, Norway.
    Vasquez, Jeddah Marie
    RISE Research Institutes of Sweden, Materials and Production, Product Realisation Methodology.
    Stensen, Wenche
    UiT The Arctic University of Norway, Norway.
    Lyvén, Benny
    RISE Research Institutes of Sweden, Materials and Production, Product Realisation Methodology.
    Svendsen, John-Sigurd
    Amicoat A/S, Norway; UiT The Arctic University of Norway, Norway.
    Svenson, Johan
    RISE Research Institutes of Sweden, Materials and Production.
    Flexible and Biocompatible Antifouling Polyurethane Surfaces Incorporating Tethered Antimicrobial Peptides through Click Reactions2023In: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195Article in journal (Refereed)
    Abstract [en]

    Efficient, simple antibacterial materials to combat implant-associated infections are much in demand. Herein, the development of polyurethanes, both cross-linked thermoset and flexible and versatile thermoplastic, suitable for “click on demand” attachment of antibacterial compounds enabled via incorporation of an alkyne-containing diol monomer in the polymer backbone, is described. By employing different polyolic polytetrahydrofurans, isocyanates, and chain extenders, a robust and flexible material comparable to commercial thermoplastic polyurethane is prepared. A series of short synthetic antimicrobial peptides are designed, synthesized, and covalently attached in a single coupling step to generate a homogenous coating. The lead material is shown to be biocompatible and does not display any toxicity against either mouse fibroblasts or reconstructed human epidermis according to ISO and OECD guidelines. The repelling performance of the peptide-coated materials is illustrated against colonization and biofilm formation by Staphylococcus aureus and Staphylococcus epidermidis on coated plastic films and finally, on coated commercial central venous catheters employing LIVE/DEAD staining, confocal laser scanning microscopy, and bacterial counts. This study presents the successful development of a versatile and scalable polyurethane with the potential for use in the medical field to reduce the impact of bacterial biofilms. 

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  • 2.
    Brooke, Darby G.
    et al.
    Cawthron Institute, New Zealand.
    Cervin, Gunnar
    University of Gothenburg, Sweden.
    Champeau, Olivier
    Cawthron Institute, New Zealand.
    Harwood, David Tim
    Cawthron Institute, New Zealand.
    Pavia, Henrik
    University of Gothenburg, Sweden.
    Selwood, Andrew I.
    Cawthron Institute, New Zealand.
    Svenson, Johan
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Tremblay, Louis A.
    Cawthron Institute, New Zealand; University of Auckland, New Zealand.
    Cahill, Patrick Louis
    Cawthron Institute, New Zealand.
    Antifouling activity of portimine, select semisynthetic analogues, and other microalga-derived spirocyclic imines2018In: Biofouling (Print), ISSN 0892-7014, E-ISSN 1029-2454, Vol. 34, no 8, p. 950-961Article in journal (Refereed)
    Abstract [en]

    A range of natural products from marine invertebrates, bacteria and fungi have been assessed as leads for nature-inspired antifouling (AF) biocides, but little attention has been paid to microalgal-derived compounds. This study assessed the AF activity of the spirocyclic imine portimine (1), which is produced by the benthic mat-forming dinoflagellate Vulcanodinium rugosum. Portimine displayed potent AF activity in a panel of four macrofouling bioassays (EC50 0.06–62.5 ng ml−1), and this activity was distinct from that of the related compounds gymnodimine-A (2), 13-desmethyl spirolide C (3), and pinnatoxin-F (4). The proposed mechanism of action for portimine is induction of apoptosis, based on the observation that portimine inhibited macrofouling organisms at developmental stages known to involve apoptotic processes. Semisynthetic modification of select portions of the portimine molecule was subsequently undertaken. Observed changes in bioactivity of the resulting semisynthetic analogues of portimine were consistent with portimine’s unprecedented 5-membered imine ring structure playing a central role in its AF activity.

  • 3.
    Cahill, P. L.
    et al.
    Cawthron Institute, New Zealand.
    Moodie, L. W. K.
    Uppsala University, Sweden.
    Hertzer, C.
    Cawthron Institute, New Zealand.
    Pinori, Emiliano
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Pavia, H.
    University of Gothenburg, Sweden.
    Hellio, C.
    Univ. Brest, France.
    Brimble, M. A.
    University of Auckland, New Zealand.
    Svenson, Johan
    Cawthron Institute, New Zealand.
    Creating New Antifoulants Using the Tools and Tactics of Medicinal Chemistry2024In: Accounts of Chemical Research, ISSN 0001-4842, E-ISSN 1520-4898, Vol. 57, p. 399-Article in journal (Refereed)
    Abstract [en]

    Conspectus The unwanted accumulation of marine micro- and macroorganisms such as algae and barnacles on submerged man-made structures and vessel hulls is a major challenge for any marine operation. Known as biofouling, this problem leads to reduced hydrodynamic efficiency, significantly increased fuel usage, microbially induced corrosion, and, if not managed appropriately, eventual loss of both performance and structural integrity. Ship hull biofouling in the international maritime transport network conservatively accounts for 0.6% of global carbon emissions, highlighting the global scale and the importance of this problem. Improved antifouling strategies to limit surface colonization are paramount for essential activities such as shipping, aquaculture, desalination, and the marine renewable energy sector, representing both a multibillion dollar cost and a substantial practical challenge. From an ecological perspective, biofouling is a primary contributor to the global spread of invasive marine species, which has extensive implications for the marine environment. Historically, heavy metal-based toxic biocides have been used to control biofouling. However, their unwanted collateral ecological damage on nontarget species and bioaccumulation has led to recent global bans. With expanding human activities within aquaculture and offshore energy, it is both urgent and apparent that environmentally friendly surface protection remains key for maintaining the function of both moving and stationary marine structures. Biofouling communities are typically a highly complex network of both micro- and macroorganisms, representing a broad section of life from bacteria to macrophytes and animals. Given this diversity, it is unrealistic to expect that a single antifouling “silver bullet” will prevent colonization with the exception of generally toxic biocides. For that reason, modern and future antifouling solutions are anticipated to rely on novel coating technologies and “combination therapies” where mixtures of narrow-spectrum bioactive components are used to provide coverage across fouling species. In contrast to the existing cohort of outdated, toxic antifouling strategies, such as copper- and tributyltin-releasing paints, modern drug discovery techniques are increasingly being employed for the rational design of effective yet safe alternatives. The challenge for a medicinal chemistry approach is to effectively account for the large taxonomic diversity among fouling organisms combined with a lack of well-defined conserved molecular targets within most taxa. The current Account summarizes our work employing the tools of modern medicinal chemistry to discover, modify, and develop optimized and scalable antifouling solutions based on naturally occurring antifouling and repelling compounds from both marine and terrestrial sources. Inspiration for rational design comes from targeted studies on allelopathic natural products, natural repelling peptides, and secondary metabolites from sessile marine organisms with clean exteriors, which has yielded several efficient and promising antifouling leads.

  • 4.
    Cahill, Patrick
    et al.
    Cawthron Institute, New Zealand.
    Grant, Thomas
    University of Auckland, New Zealand.
    Rennison, David
    University of Auckland, New Zealand.
    Champeau, Olivier
    Cawthron Institute, New Zealand.
    Boundy, Michael
    Cawthron Institute, New Zealand.
    Passfield, Emillie
    Cawthron Institute, New Zealand.
    Berglin, Mattias
    RISE Research Institutes of Sweden, Materials and Production, Product Realisation Methodology.
    Brimble, Margaret
    University of Auckland, New Zealand.
    Svenson, Johan
    Cawthron Institute, New Zealand.
    Nature-Inspired Peptide Antifouling Biocide: Coating Compatibility, Field Validation, and Environmental Stability2023In: ACS Applied Bio Materials, E-ISSN 2576-6422, Vol. 6, no 6, p. 2415-2425Article in journal (Refereed)
    Abstract [en]

    This study reports the development of a class of eco-friendly antifouling biocides based on a cyclic dipeptide scaffold, 2,5-diketopiperazine (2,5-DKP). The lead compound cyclo(N-Bip-l-Arg-N-Bip-l-Arg) (1) was synthesized in gram amounts and used to assess the compatibility with an ablation/hydration coating, efficacy against biofouling, and biodegradation. Leaching of 1 from the coating into seawater was assessed via a rotating drum method, revealing relatively stable and predictable leaching rates under dynamic shear stress conditions (36.1 ± 19.7 to 25.2 ± 9.1 ng-1 cm-2 day-1) but low or no leaching under static conditions. The coatings were further analyzed using time-of-flight secondary ion mass spectrometry (ToF-SIMS), with 1 seen to localize at the surface of the coating in a surfactant-like fashion. When coatings were deployed in the ocean, detectable reductions in biofouling development were measured for up to 11 weeks. After this time, biofouling overwhelmed the performance of the coating, consistent with leaching kinetics. Biodegradation of 1 in seawater was assessed using theoretical oxygen demand and analytical quantification. Masking effects were observed at higher concentrations of 1 due to antimicrobial properties, but half-lives were calculated ranging from 13.4 to 16.2 days. The results can rationally inform future development toward commercial antifouling products. 

  • 5.
    Greco, Ines
    et al.
    University of Copenhagen, Denmark.
    Molchanova, Natalia
    Roskilde University, Denmark; Lawrence Berkeley National Laboratory, USA.
    Holmedal, Elin
    RISE Research Institutes of Sweden.
    Jenssen, Håvard
    Roskilde University, Denmark.
    Hummel, Bernard D
    Zoetis Inc, USA.
    Watts, Jeffrey L
    Zoetis Inc, USA.
    Håkansson, Joakim
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles.
    Hansen, Paul R
    University of Copenhagen, Denmark.
    Svenson, Johan
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles. Cawthron Institute, New Zealand; University of Gothenburg, Sweden.
    Correlation between hemolytic activity, cytotoxicity and systemic in vivo toxicity of synthetic antimicrobial peptides.2020In: Scientific Reports, E-ISSN 2045-2322, Vol. 10, no 1, article id 13206Article in journal (Refereed)
    Abstract [en]

    The use of non-standard toxicity models is a hurdle in the early development of antimicrobial peptides towards clinical applications. Herein we report an extensive in vitro and in vivo toxicity study of a library of 24 peptide-based antimicrobials with narrow spectrum activity towards veterinary pathogens. The haemolytic activity of the compounds was evaluated against four different species and the relative sensitivity against the compounds was highest for canine erythrocytes, intermediate for rat and human cells and lowest for bovine cells. Selected peptides were additionally evaluated against HeLa, HaCaT and HepG2 cells which showed increased stability towards the peptides. Therapeutic indexes of 50-500 suggest significant cellular selectivity in comparison to bacterial cells. Three peptides were administered to rats in intravenous acute dose toxicity studies up to 2-8 × MIC. None of the injected compounds induced any systemic toxic effects in vivo at the concentrations employed illustrating that the correlation between the different assays is not obvious. This work sheds light on the in vitro and in vivo toxicity of this class of promising compounds and provides insights into the relationship between the different toxicity models often employed in different manners to evaluate the toxicity of novel bioactive compounds in general.

  • 6.
    Herzberg, Moshe
    et al.
    Ben-Gurion University of the Negev, Israel.
    Berglin, Mattias
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles. Gothenburg University, Sweden.
    Eliahu, Sarai
    Ben-Gurion University of the Negev, Israel.
    Bodin, Lovisa
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles.
    Agrenius, Karin
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles.
    Zlotkin, Amir
    DisperseBio Ltd, Israel.
    Svenson, Johan
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles.
    Efficient prevention of marine biofilm formation employing a surface-grafted repellent marine peptide2021In: ACS Applied Bio Materials, E-ISSN 2576-6422, Vol. 4, no 4, p. 3360-3373Article in journal (Refereed)
    Abstract [en]

    Creation of surfaces resistant to the formation of microbial biofilms via biomimicry has been heralded as a promising strategy to protect a range of different materials ranging from boat hulls to medical devices and surgical instruments. In our current study, we describe the successful transfer of a highly effective natural marine biofilm inhibitor to the 2D surface format. A series of cyclic peptides inspired by the natural equinatoxin II protein produced by Beadlet anemone (Actinia equine) have been evaluated for their ability to inhibit the formation of a mixed marine microbial consortium on polyamide reverse osmosis membranes. In solution, the peptides are shown to effectively inhibit settlement and biofilm formation in a nontoxic manner down to 1 nM concentrations. In addition, our study also illustrates how the peptides can be applied to disperse already established biofilms. Attachment of a hydrophobic palmitic acid tail generates a peptide suited for strong noncovalent surface interactions and allows the generation of stable noncovalent coatings. These adsorbed peptides remain attached to the surface at significant shear stress and also remain active, effectively preventing the biofilm formation over 24 h. Finally, the covalent attachment of the peptides to an acrylate surface was also evaluated and the prepared coatings display a remarkable ability to prevent surface colonization at surface loadings of 55 ng/cm2 over 48 h. The ability to retain the nontoxic antibiofilm activity, documented in solution, in the covalent 2D-format is unprecedented, and this natural peptide motif displays high potential in several material application areas.

  • 7.
    Håkansson, Joakim
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles. Gothenburg University, Sweden.
    Cavanagh, J. P.
    Amicoat A/S, Norway; UiT The Arctic University of Norway, Norway.
    Stensen, W.
    UiT The Arctic University of Norway, Norway.
    Mortensen, B.
    Amicoat A/S, Norway.
    Svendsen, J. -S
    UiT The Arctic University of Norway, Norway; Amicoat A/S, Norway.
    Svenson, Johan
    RISE Research Institutes of Sweden. Cawthron Institute, New Zealand.
    In vitro and in vivo antibacterial properties of peptide AMC-109 impregnated wound dressings and gels2021In: Journal of Antibiotics, ISSN 0021-8820, E-ISSN 1881-1469, Vol. 74, p. 337-345Article in journal (Refereed)
    Abstract [en]

    Synthetic mimics of antimicrobial peptides (AMPs) is a promising class of molecules for a variety of antimicrobial applications. Several hurdles must be passed before effective systemic infection therapies with AMPs can be achieved, but the path to effective topical treatment of skin, nail, and soft tissue infections appears less challenging to navigate. Skin and soft tissue infection is closely coupled to the emergence of antibiotic resistance and represents a major burden to the healthcare system. The present study evaluates the promising synthetic cationic AMP mimic, AMC-109, for treatment of skin infections in vivo. The compound is evaluated both in impregnated cotton wound dressings and in a gel formulation against skin infections caused by Staphylococcus aureus and methicillin resistant S. aureus. Both the ability to prevent colonization and formation of an infection, as well as eradicate an ongoing infection in vivo with a high bacterial load, were evaluated. The present work demonstrates that AMC-109 displays a significantly higher antibacterial activity with up to a seven-log reduction in bacterial loads compared to current clinical standard therapy; Altargo cream (1% retapamulin) and Fucidin cream (2% fusidic acid) in the in vivo wound models. It is thus concluded that AMC-109 represents a promising entry in the development of new and effective remedies for various skin infections. © 2021, The Author(s)

  • 8.
    Karlsen, Eskil
    et al.
    Amicoat AS, Norway; Arctic University of Norway, Norway.
    Stensen, Wenche
    Amicoat AS, Norway: Arctic University of Norway, Norway.
    Juskewitz, Eric
    Arctic University of Norway, Norway.
    Svenson, Johan
    RISE Research Institutes of Sweden.
    Berglin, Mattias
    RISE Research Institutes of Sweden, Materials and Production, Product Realisation Methodology.
    Svendsen, John Sigurd
    Amicoat AS, Norway; Arctic University of Norway, Norway.
    Anti-colonization effect of au surfaces with self-assembled molecular monolayers functionalized with antimicrobial peptides on s. Epidermidis2021In: Antibiotics, ISSN 0066-4774, E-ISSN 2079-6382, Vol. 10, no 12, article id 1516Article in journal (Refereed)
    Abstract [en]

    Medical devices with an effective anti-colonization surface are important tools for com-batting healthcare-associated infections. Here, we investigated the anti-colonization efficacy of antimicrobial peptides covalently attached to a gold model surface. The gold surface was modified by a self-assembled polyethylene glycol monolayer with an acetylene terminus. The peptides were covalently connected to the surface through a copper-catalyzed [3 + 2] azide-acetylene coupling (CuAAC). The anti-colonization efficacy of the surfaces varied as a function of the antimicrobial activity of the peptides, and very effective surfaces could be prepared with a 6 log unit reduction in bacterial colonization. © 2021 by the authors. 

  • 9.
    Labriere, Christophe
    et al.
    UiT The Arctic University of Norway, Norway.
    Andersen, Jeanette
    UiT The Arctic University of Norway, Norway.
    Albrigtsen, Marte
    UiT The Arctic University of Norway, Norway.
    Hansen, Jörn
    UiT The Arctic University of Norway, Norway.
    Svenson, Johan
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials. UiT The Arctic University of Norway, Norway.
    Heterocyclic cellular lipid peroxidation inhibitors inspired by the marine antioxidant barettin2019In: Bioorganic chemistry (Print), ISSN 0045-2068, Vol. 84, p. 106-114Article in journal (Refereed)
    Abstract [en]

    The marine environment remains a rich source for the discovery and development of novel bioactive compounds. The present paper describes the design, synthesis and biological evaluation of a library of small molecule heterocyclic mimetics of the marine 2,5-diketopiperazine barettin which is a powerful natural antioxidant. By mainly focusing on the influence from the brominated indole and heterocyclic core of barettin, a library of 19 compounds was prepared. The compounds comprised a heterocyclic core, either a 2,5 diketopiperazine, an imidazolidinedione or a thioxothiazolidinone, which were mainly monosubstituted with ranging bulky substituents. The prepared compounds were screened for activity in a cellular lipid peroxidation assay using HepG2 cells. Several of the synthetic compounds showed antioxidant properties superior to the positive control barettin. Two of the prepared compounds displayed inhibitory activity similar to commercial antioxidants with significant inhibition at low µg/mL concentrations. The toxicity of the compounds was also investigated against MRC-5 lung fibroblasts and none of the included compounds displayed any toxicity at 50 µg/mL.

  • 10.
    Labriere, Chrostophe
    et al.
    UiT The Arctic University of Norway, Norway.
    Elumalai, Vijayaragavan
    UiT The Arctic University of Norway, Norway.
    Staffansson, Jannie
    UiT The Arctic University of Norway, Norway.
    Cervin, Gunnar
    University of Gothenburg, Sweden.
    Le Norcy, Tiffany
    University Bretagne-Sud, France.
    Denardou, Hugo
    UiT The Arctic University of Norway, Norway.
    Réhel, Karine Vallée
    University Bretagne-Sud, France.
    Moodie, Lindon W.K.
    Uppsala University, Sweden.
    Hellio, Claire
    Université de Bretagne Occidentale, France.
    Pavia, Henrik
    University of Gothenburg, Sweden.
    Hansen, Jørn H.
    UiT The Arctic University of Norway, Norway.
    Svenson, Johan
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles. UiT The Arctic University of Norway, Norway.
    Phidianidine A and synthetic analogues as naturally inspired marine antifoulants2020In: Journal of Natural Products, ISSN 0163-3864, E-ISSN 1520-6025, Vol. 83, no 11, p. 3413-3423Article in journal (Refereed)
    Abstract [en]

    Stationary and slow-moving marine organisms regularly employ a natural product chemical defense to prevent being colonized by marine micro- and macroorganisms. While these natural antifoulants can be structurally diverse, they often display highly conserved chemistries and physicochemical properties, suggesting a natural marine antifouling pharmacophore. In our current report, we investigate the marine natural product phidianidine A, which displays several chemical properties found in highly potent marine antifoulants. Phidianidine A and synthetic analogues were screened against the settlement and metamorphosis of Amphibalanus improvisus cyprids, and several of the compounds displayed inhibitory activities at low micromolar concentrations with IC50 values down to 0.7 μg/mL observed. The settlement study highlights that phidianidine A is a potent natural antifoulant and that the scaffold can be tuned to generate simpler and improved synthetic analogues. The bioactivity is closely linked to the size of the compound and to its basicity. The study also illustrates that active analogues can be prepared in the absence of the natural constrained 1,2,4-oxadiazole ring. A synthetic lead analogue of phidianidine A was incorporated in a coating and included in antifouling field trials, where it was shown that the coating induced potent inhibition of marine bacteria and microalgae settlement.

  • 11.
    Labrière, Christophe
    et al.
    UiT The Arctic University of Norway, Norway.
    Kondori, Nahid
    University of Gothenburg, Sweden.
    Seth Caous, Josefin
    RISE - Research Institutes of Sweden (2017-2019), Bioscience and Materials, Chemistry and Materials.
    Boomgaren, Marc
    UiT The Arctic University of Norway, Norway.
    Sandholm, Kerstin
    Linnaeus University, Sweden.
    Ekdahl, Kristina. N.
    Linnaeus University, Sweden; Uppsala University, Sweden.
    Hansen, Jörn H.
    UiT The Arctic University of Norway, Norway.
    Svenson, Johan
    RISE - Research Institutes of Sweden (2017-2019), Bioscience and Materials, Chemistry and Materials. UiT The Arctic University of Norway, Norway.
    Development and evaluation of cationic amphiphilic antimicrobial 2,5-diketopiperazines2018In: Journal of Peptide Science, ISSN 1075-2617, E-ISSN 1099-1387, Vol. 24, no 7, article id e3090Article in journal (Refereed)
    Abstract [en]

    Both pathogenic bacteria and fungi are developing resistance to common antimicrobial treatment at an alarming rate. To counteract this development, it is of essence to develop new classes of antimicrobial agents. One such class is antimicrobial peptides, most of which are derived from the innate immune system. In this study, a series of novel 2,5-diketopiperazines were designed, synthesized, and evaluated for their antimicrobial abilities. The compounds were designed to probe the pharmacophore dictated for short linear mimics of antimicrobial cationic peptides, and as such, the compounds contain a range of cationic and hydrophobic functionalities. Several of the prepared compounds displayed high antimicrobial activities toward bacteria and also against human pathogenic fungi. Of particular interest was the high activity toward fungal strains with an inherent increased resistance toward conventional antifungal agents. The most effective compounds displayed inhibition of Candida glabrata and Candida krusei growth at concentrations between 4 and 8 μg/mL, which is comparable to commercial antifungal agents in use. Structure activity relationship studies revealed a similar dependence on cationic charge and the volume of the hydrophobic bulk as for linear cationic antimicrobial peptides. Finally, the hemolytic activity of selected compounds was evaluated, which revealed a potential to produce active compounds with attenuation of unwanted hemolysis. The findings highlight the potential of cyclic cationic amphiphilic peptidomimetics as a class of promising compounds for the treatment of infections caused by microorganisms with an increased resistance to conventional antimicrobial agents. © 2018 European Peptide Society and John Wiley & Sons, Ltd.

  • 12.
    Moodie, Lindon W. K.
    et al.
    UiT The Arctic University of Norway, Norway; Umeå University, Sweden.
    Cervin, Gunnar
    University of Gothenburg, Sweden.
    Trepos, Rozenn
    Université de Bretagne Occidentale, France.
    Labriere, Christophe
    UiT The Arctic University of Norway, Norway.
    Hellio, Claire
    Université de Bretagne Occidentale, France.
    Pavia, Henrik
    University of Gothenburg, Sweden.
    Svenson, Johan
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials. UiT The Arctic University of Norway, Norway.
    Design and Biological Evaluation of Antifouling Dihydrostilbene Oxime Hybrids2018In: Marine Biotechnology, ISSN 1436-2228, E-ISSN 1436-2236, Vol. 20, no 2, p. 257-267Article in journal (Refereed)
    Abstract [en]

    By combining the recently reported repelling natural dihydrostilbene scaffold with an oxime moiety found in many marine antifoulants, a library of nine antifouling hybrid compounds was developed and biologically evaluated. The prepared compounds were shown to display a low antifouling effect against marine bacteria but a high potency against the attachment and growth of microalgae down to MIC values of 0.01 μg/mL for the most potent hybrid. The mode of action can be characterized as repelling via a reversible non-toxic biostatic mechanism. Barnacle cyprid larval settlement was also inhibited at low μg/mL concentrations with low levels or no toxicity observed. Several of the prepared compounds performed better than many reported antifouling marine natural products. While several of the prepared compounds are highly active as antifoulants, no apparent synergy is observed by incorporating the oxime functionality into the dihydrostilbene scaffold. This observation is discussed in light of recently reported literature data on related marine natural antifoulants and antifouling hybrids as a potentially general strategy for generation of improved antifoulants. 

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  • 13.
    Moodie, Lindon W. K.
    et al.
    University of Umeå, Sweden .
    Sepčić, Kristina
    University of Ljubljana, Slovenia .
    Turk, Tom
    University of Ljubljana, Slovenia .
    FrangeŽ, Robert
    University of Ljubljana, Slovenia .
    Svenson, Johan
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Natural cholinesterase inhibitors from marine organisms2019In: Natural product reports (Print), ISSN 0265-0568, E-ISSN 1460-4752, Vol. 36, no 8, p. 1053-1092Article in journal (Refereed)
    Abstract [en]

    Covering: Published between 1974 up to 2018Inhibition of cholinesterases is a common approach for the management of several disease states. Most notably, cholinesterase inhibitors are used to alleviate the symptoms of neurological disorders like dementia and Alzheimer's disease and treat myasthenia gravis and glaucoma. Historically, most drugs of natural origin have been isolated from terrestrial sources and inhibitors of cholinesterases are no exception. However, the last 50 years have seen a rise in the quantity of marine natural products with close to 25 000 reported in the scientific literature. A number of marine natural products with potent cholinesterase inhibitory properties have also been reported; isolated from a variety of marine sources from algae to ascidians. Representing a diverse range of structural classes, these compounds provide inspirational leads that could aid the development of therapeutics. The current paper aims to, for the first time, comprehensively summarize the literature pertaining to cholinesterase inhibitors derived from marine sources, including the first papers published in 1974 up to 2018. The review does not report bioactive extracts, only isolated compounds, and a specific focus lies on compounds with reported dose-response data. In vivo and mechanistic data is included for compounds where this is reported. In total 185 marine cholinesterase inhibitors and selected analogs have been identified and reported and some of the compounds display inhibitory activities comparable or superior to cholinesterase inhibitors in clinical use.

  • 14.
    Moodie, Lindon W. K.
    et al.
    UiT The Arctic University of Norway, Norway.
    Žužek, Monika C.
    University of Ljubljana, Slovenia.
    Frangež, Robert
    University of Ljubljana, Slovenia.
    Andersen, Jeanette H.
    UiT The Arctic University of Norway, Norway.
    Hansen, Espen
    UiT The Arctic University of Norway, Norway.
    Olsen, Elisabeth K.
    UiT The Arctic University of Norway, Norway.
    Cergolj, Marija
    University of Ljubljana, Slovenia; University of Rijeka, Croatia.
    Sepčić, Kristina
    University of Ljubljana, Slovenia.
    Hansen, Kine Ø
    UiT The Arctic University of Norway, Norway.
    Svenson, Johan
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Medicinteknik. UiT The Arctic University of Norway, Norway.
    Synthetic analogs of stryphnusin isolated from the marine sponge: Stryphnus fortis inhibit acetylcholinesterase with no effect on muscle function or neuromuscular transmission2016In: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 14, no 47, p. 11220-11229Article in journal (Refereed)
    Abstract [en]

    The marine secondary metabolite stryphnusin (1) was isolated from the boreal sponge Stryphnus fortis, collected off the Norwegian coast. Given its resemblance to other natural acetylcholinesterase antagonists, it was evaluated against electric eel acetylcholinesterase and displayed inhibitory activity. A library of twelve synthetic phenethylamine analogs, 2a-7a and 2b-7b, containing tertiary and quaternary amines respectively were synthesized to investigate the individual structural contributions to the activity. Compound 7b was the strongest competitive inhibitor of both acetylcholinesterase and butyrylcholinesterase with IC50 values of 57 and 20 μM, respectively. This inhibitory activity is one order of magnitude higher than the positive control physostigmine, and is comparable with several other marine acetylcholinesterase inhibitors. The physiological effect of compound 7b on muscle function and neuromuscular transmission was studied and revealed a selective mode of action at the investigated concentration. This data is of importance as the interference of therapeutic acetylcholinesterase inhibitors with neuromuscular transmission can be problematic and lead to unwanted side effects. The current findings also provide additional insights into the structure-activity relationship of both natural and synthetic acetylcholinesterase inhibitors.

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  • 15.
    Olsen, Elisabeth K.
    et al.
    UiT The Arctic University of Norway, Norway.
    Hansen, Espen
    UiT The Arctic University of Norway, Norway.
    Moodie, Lindon W. K.
    University of Umeå, Sweden.
    Isaksson, Johan
    UiT The Arctic University of Norway, Norway.
    Sepčić, Kristina
    University of Ljubljana, Slovenia.
    Cergolj, Marija
    University of Ljubljana, Slovenia; University of Rijeka, Croatia.
    Svenson, Johan
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Medicinteknik.
    Andersen, Jeanette H.
    UiT The Arctic University of Norway, Norway.
    Marine AChE inhibitors isolated from Geodia barretti: Natural compounds and their synthetic analogs2016In: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 14, no 5, p. 1629-1640Article in journal (Refereed)
    Abstract [en]

    Barettin, 8,9-dihydrobarettin, bromoconicamin and a novel brominated marine indole were isolated from the boreal sponge Geodia barretti collected off the Norwegian coast. The compounds were evaluated as inhibitors of electric eel acetylcholinesterase. Barettin and 8,9-dihydrobarettin displayed significant inhibition of the enzyme, with inhibition constants (Ki) of 29 and 19 μM respectively towards acetylcholinesterase via a reversible noncompetitive mechanism. These activities are comparable to those of several other natural acetylcholinesterase inhibitors of marine origin. Bromoconicamin was less potent against acetylcholinesterase, and the novel compound was inactive. Based on the inhibitory activity, a library of 22 simplified synthetic analogs was designed and prepared to probe the role of the brominated indole, common to all the isolated compounds. From the structure-activity investigation it was shown that the brominated indole motif is not sufficient to generate a high acetylcholinesterase inhibitory activity, even when combined with natural cationic ligands for the acetylcholinesterase active site. The four natural compounds were also analysed for their butyrylcholinesterase inhibitory activity in addition and shown to display comparable activities. The study illustrates how both barettin and 8,9-dihydrobarettin display additional bioactivities which may help to explain their biological role in the producing organism. The findings also provide new insights into the structure-activity relationship of both natural and synthetic acetylcholinesterase inhibitors.

  • 16.
    Solstad, Runar Gjerp
    et al.
    UiT The Arctic University of Norway, Norway.
    Li, Chun
    UiT The Arctic University of Norway, Norway.
    Isaksson, Johan
    UiT The Arctic University of Norway, Norway.
    Johansen, Jostein
    UiT The Arctic University of Norway, Norway.
    Svenson, Johan
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Medicinteknik. UiT The Arctic University of Norway, Norway.
    Stensvåg, Klara
    UiT The Arctic University of Norway, Norway.
    Haug, Tor
    UiT The Arctic University of Norway, Norway.
    Novel antimicrobial peptides EeCentrocins 1, 2 and EeStrongylocin 2 from the Edible sea urchin Echinus esculentus have 6-br-trp post-translational modifications2016In: PLOS ONE, E-ISSN 1932-6203, Vol. 11, no 3, article id e0151820Article in journal (Refereed)
    Abstract [en]

    The global problem of microbial resistance to antibiotics has resulted in an urgent need to develop new antimicrobial agents. Natural antimicrobial peptides are considered promising candidates for drug development. Echinoderms, which rely on innate immunity factors in the defence against harmful microorganisms, are sources of novel antimicrobial peptides. This study aimed to isolate and characterise antimicrobial peptides from the Edible sea urchin Echinus esculentus. Using bioassay-guided purification and cDNA cloning, three antimicrobial peptides were characterised from the haemocytes of the sea urchin; two heterodimeric peptides and a cysteine-rich peptide. The peptides were named EeCentrocin 1 and 2 and EeStrongylocin 2, respectively, due to their apparent homology to the published centrocins and strongylocins isolated from the green sea urchin Strongylocentrotus droebachiensis. The two centrocin-like peptides EeCentrocin 1 and 2 are intramolecularly connected via a disulphide bond to form a heterodimeric structure, containing a cationic heavy chain of 30 and 32 amino acids and a light chain of 13 amino acids. Additionally, the light chain of EeCentrocin 2 seems to be N-terminally blocked by a pyroglutamic acid residue. The heavy chains of EeCentrocins 1 and 2 were synthesised and shown to be responsible for the antimicrobial activity of the natural peptides. EeStrongylocin 2 contains 6 cysteines engaged in 3 disulphide bonds. A fourth peptide (Ee4635) was also discovered but not fully characterised. Using mass spectrometric and NMR analyses, EeCentrocins 1 and 2, EeStrongylocin 2 and Ee4635 were all shown to contain post-translationally brominated Trp residues in the 6 position of the indole ring.

  • 17.
    Stensen, Wenche
    et al.
    UiT The Arctic University of Norway, Norway; Lytix Biopharma AS, Norway.
    Turner, Rob
    MedPharm Ltd, UK.
    Brown, Marc
    MedPharm Ltd, UK; University of Hertfordshire, UK.
    Kondori, Nahid
    University of Gothenburg, Sweden.
    Svendsen, John Sigurd
    UiT The Arctic University of Norway, Norway; Lytix Biopharma AS, Norway.
    Svenson, Johan
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Medicinteknik.
    Short cationic antimicrobial peptides display superior antifungal activities toward Candidiasis and Onychomycosis in comparison with Terbinafine and Amorolfine2016In: Molecular Pharmaceutics, ISSN 1543-8384, E-ISSN 1543-8392, Vol. 13, no 10, p. 3595-3600Article in journal (Refereed)
    Abstract [en]

    Novel antifungals are in high demand due to the challenges associated with resistant, persistent, and systemic fungal infections. Synthetic mimics of antimicrobial peptides are emerging as a promising class of compounds for antifungal treatment. In the current study, five synthetic cationic antimicrobial tripeptides were evaluated as antifungal therapeutics against 24 pathogenic strains of fungi. Three of the peptides displayed strong general antifungal properties at low micromolar inhibitory concentrations. The most promising peptide, compound 5, was selected and evaluated as an antifungal remedy for Candida albicans candidiasis in a human skin model and for the treatment of Trichophyton rubrum induced onychomycosis in an infected human nail model. Compound 5 was shown to display antifungal properties and a rapid mode of action superior to those of both the commercial comparators Loceryl and Lamisil. Compound 5 was also active against a clinical isolate of Candida albicans with acquired fluconazole resistance.

  • 18.
    Svendsen, John
    et al.
    UiT The Arctic University of Norway, Norway.
    Grant, Thomas
    University of Auckland, New Zealand.
    Rennison, David
    University of Auckland, New Zealand.
    Brimble, Margaret
    University of Auckland, New Zealand.
    Svenson, Johan
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Very Short and Stable Lactoferricin-Derived Antimicrobial Peptides: Design Principles and Potential Uses2019In: Accounts of Chemical Research, ISSN 0001-4842, E-ISSN 1520-4898, Vol. 52, no 3, p. 749-759Article in journal (Refereed)
    Abstract [en]

    ConspectusThe alarming rate at which micro-organisms are developing resistance to conventional antibiotics represents one of the global challenges of our time. There is currently ample space in the antibacterial drug pipeline, and scientists are trying to find innovative and novel strategies to target the microbial enemies. Nature has remained a source of inspiration for most of the antibiotics developed and used, and the immune molecules produced by the innate defense systems, as a first line of defense, have been heralded as the next source of antibiotics. Most living organisms produce an arsenal of antimicrobial peptides (AMPs) to rapidly fend off intruding pathogens, and several different attempts have been made to transform this versatile group of compounds into the next generation of antibiotics. However, faced with the many hurdles of using peptides as drugs, the success of these defense molecules as therapeutics remains to be realized. AMPs derived from the proteolytic degradation of the innate defense protein lactoferrin have been shown to display several favorable antimicrobial properties. In an attempt to investigate the biological and pharmacological properties of these much shorter AMPs, the sequence dependence was investigated, and it was shown, through a series of truncation experiments, that these AMPs in fact can be prepared as tripeptides, with improved antimicrobial activity, via the incorporation of unnatural hydrophobic residues and terminal cappings. In this Account, we describe how this class of promising cationic tripeptides has been developed to specifically address the main challenges limiting the general use of AMPs. This has been made possible through the identification of the antibacterial pharmacophore and via the incorporation of a range of unnatural hydrophobic and cationic amino acids. Incorporation of these residues at selected positions has allowed us to extensively establish how these compounds interact with the major proteolytic enzymes trypsin and chymotrypsin and also the two major drug-binding plasma proteins serum albumin and α-1 glycoprotein. Several of the challenges associated with using AMPs relate to their size, susceptibility to rapid proteolytic degradation, and poor oral bioavailability. Our studies have addressed these issues in detail, and the results have allowed us to effectively design and prepare active and metabolically stable AMPs that have been evaluated in a range of functional settings. The optimized short AMPs display inhibitory activities against a plethora of micro-organisms at low micromolar concentrations, and they have been shown to target resistant strains of both bacteria and fungi alike with a very rapid mode of action. Our Account further describes how these compounds behave in in vivo experiments and highlights both the challenges and possibilities of the intriguing compounds. In several areas, they have been shown to exhibit comparable or superior activity to established antibacterial, antifungal, and antifouling commercial products. This illustrates their ability to effectively target and eradicate various microbes in a variety of settings ranging from the ocean to the clinic.

  • 19.
    Svenson, Johan
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Medicinteknik.
    På jakt efter nya läkemedel i Ishavet2016In: Naturvetare, ISSN 2000-2424, Vol. 6, p. 24-28Article in journal (Other (popular science, discussion, etc.))
    Abstract [sv]

    Ungefär en tredjedel av alla läkemedel har sin källa i naturen. Forskaren Johan Svenson skriver själv om sin expedition i Arktis, där forskarna samlar in alger och andra organismer i sökandet efter nya molekyler, som till exempel kan bli ny antibiotika.

  • 20.
    Trepos, Rozenn
    et al.
    University of Portsmouth, UK.
    Cervin, Gunnar
    University of Gothenburg, Sweden.
    Pile, Claire
    University of Portsmouth, UK.
    Pavia, Henrik
    University of Gothenburg, Sweden.
    Hellio, Claire
    University of Western Brittany, France.
    Svenson, Johan
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor. UiT The Arctic University of Norway, Norway.
    Evaluation of cationic micropeptides derived from the innate immune system as inhibitors of marine biofouling2015In: Biofouling (Print), ISSN 0892-7014, E-ISSN 1029-2454, Vol. 31, no 4, p. 393-403Article in journal (Refereed)
    Abstract [en]

    A series of 13 short synthetic amphiphilic cationic micropeptides, derived from the antimicrobial iron-binding innate defence protein lactoferrin, have been evaluated for their capacity to inhibit the marine fouling process. The whole biofouling process was studied and microfouling organisms such as marine bacteria and microalgae were included as well as the macrofouling barnacle Balanus improvisus. In total 19 different marine fouling organisms (18 microfoulers and one macrofouler) were included and both the adhesion and growth of the microfoulers were investigated. It was shown that the majority of the peptides inhibited barnacle cyprid settlement via a reversible nontoxic mechanism, with IC50 values as low as 0.5 μg ml−1. Six peptides inhibited adhesion and growth of microorganisms. Two of these were particularly active against the microfoulers with MIC-values ranging between 0.01 and 1 μg ml−1, which is comparable with the commercial reference antifoulant SeaNine.

  • 21.
    Vinagre, Pedro
    et al.
    WavEC Offshore Renewables, Portugal.
    Lindén, Johan B
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Mardaras, Enara
    Basque Research and Technology Alliance, Spain.
    Pinori, Emiliano
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Svenson, Johan
    Cawthron Institute, New Zealand.
    Probing the correlation between corrosion resistance and biofouling of thermally sprayed metallic substrata in the field2022In: Biofouling (Print), ISSN 0892-7014, E-ISSN 1029-2454, Vol. 38, no 2, p. 147-161Article in journal (Refereed)
    Abstract [en]

    The correlation between inherent corrosion resistance and biofouling was investigated for five different metallic coatings. Steel panels thermally spray-coated with either aluminium, Monel, bronze or different aluminium alloys were tested in controlled salt mist conditions and electrochemical corrosion tests and subsequently employed at sea. The biofouling of the panels was monitored at different depths (5, 10 and 15 m) at periods ranging from 5 to 12 months. The main macrofouling organisms were quantified and analysed using permutational multivariate analysis. The results indicate a significant difference in fouling pressure between depths and the geographic sites used. No statistically significant link between high corrosion resistance and lower biofouling pressure was observed, indicating that the main marine macrofoulers settled equally well on corrosion resistant and corrosion prone metallic surfaces. This work sheds light on biofouling of thermally sprayed metallic substrata and it characterizes and compares biofouling assemblages from different biogeographical regions in Europe. 

  • 22.
    Vinagre, Pedro
    et al.
    WavEC Offshore Renewables, Portugal.
    Simas, Teresa
    WavEC Offshore Renewables, Portugal.
    Cruz, Erica
    WavEC Offshore Renewables, Portugal.
    Pinori, Emiliano
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles.
    Svenson, Johan
    RISE Research Institutes of Sweden, Materials and Production, Chemistry, Biomaterials and Textiles. Cawthron Institute, New Zealand.
    Marine biofouling: A European database for the marine renewable energy sector2020In: Journal of Marine Science and Engineering, E-ISSN 2077-1312, Vol. 8, no 8, article id 495Article in journal (Refereed)
    Abstract [en]

    Biofouling is a major problem shared among all maritime sectors employing submerged structures where it leads to substantially increased costs and lowered operational lifespans if poorly addressed. Insight into the ongoing processes at the relevant marine locations is key to effective management of biofouling. Of specific concern for the marine renewable energy (MRE) sector is the fact that information on biofouling composition and magnitude across geographies is dispersed throughout published papers and consulting reports. To enable rapid access to relevant key biofouling events the present work describes a European biofouling database to support the MRE sector and other maritime industries. The database compiles in one document qualitative and quantitative data for challenging biofouling groups, including non-native species associated with MRE and related marine equipment, in different European Ecoregions. It provides information on the occurrence of fouling species and data on key biofouling parameters, such as biofouling thickness and weight. The database aims to aid the MRE sector and offshore industries in understanding which biofouling communities their devices are more susceptible to at a given site, to facilitate informed decisions. In addition, the biofouling mapping is useful for the development of biosecurity risk management plans as well as academic research. © 2020 by the authors.

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