RESUMEN
Soil sustains human life by nourishing crops, storing food sources, and housing microbes, which may affect the nutrition and biosynthesis of secondary metabolites, some of which are used as drugs. To identify lead compounds for a new class of drugs, we collected soil-derived fungal strains from various environments, including urban areas. As various human pathogens are assumed to influence the biosynthetic pathways of metabolites in soil fungi, leading to the production of novel scaffolds, we focused our work on densely populated urban areas and tourist attractions. A soil-derived fungal extract library was screened against MDA-MB-231 cells to derive their cytotoxic activity. Notably, 10 µg/mL of the extract of Trichoderma guizhouense (DS9-1) was found to exhibit an inhibitory effect of 71%. Fractionation, isolation, and structure elucidation efforts led to the identification of nine new peptaibols, trichoguizaibols A-I (1-9), comprising 14 amino acid residues (14-AA peptaibols), and three new peptaibols, trichoguizaibols J-L (10-12), comprising 18 amino acid residues (18-AA peptaibols). The chemical structures of 1-12 were determined based on their 1D and 2D NMR spectra, HRESIMS, electronic circular dichroism data, and results of the advanced Marfey's method. The 18-AA peptaibols were found to exhibit cytotoxicity against MDA-MB-231, SK-Hep1, SKOV3, DU145, and HCT116 cells greater than that of the 14-AA peptaibols. Among these compounds, 10-12 exhibited potent sub-micromolar IC50 values. These results are expected to shed light on a new direction for developing novel scaffolds as anticancer agents.
Asunto(s)
Peptaiboles , Microbiología del Suelo , Trichoderma , Humanos , Trichoderma/química , Peptaiboles/farmacología , Peptaiboles/química , Estructura Molecular , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Ensayos de Selección de Medicamentos Antitumorales , Línea Celular TumoralRESUMEN
Five new lipopeptaibols (1-5) and eight new 19-residue peptaibols (8-15) along with two known lipopeptaibols, lipovelutibols C (6) and D (7) were isolated from Trichoderma strigosum. The planar structures of the newly discovered peptaibols (1-5, 8-15) were elucidated using 1D and 2D NMR, and UPLC-MS/MS data. The absolute configurations for new peptaibols (1-5, 8-15) were elucidated using the advanced Marfey's method and GITC (2,3,4,6-tetra-O-acetyl-ß-d-glucopyranosyl isothiocyanate) derivatization. Through analysis of CD spectra, these peptabols were found to have right-handed helical conformations. While most of the new compounds were significantly more active than the positive control, 9, 10, 12, and 15 containing Ser and Leu at positions 10 and 11, respectively, were the most cytotoxic against MDA-MB-231, SNU449, SKOV3, DU145, and HCT116 cancer cell lines, and the 19-residue peptaibols were generally more potent than lipopeptaibols.
Asunto(s)
Peptaiboles , Trichoderma , Peptaiboles/farmacología , Peptaiboles/química , Humanos , Trichoderma/química , Estructura Molecular , Ensayos de Selección de Medicamentos Antitumorales , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificaciónRESUMEN
Peptaibols are a class of short peptides, typically 7 to 20 amino acids long, characterized by noncanonical amino acid residues such as aminoisobutyric acid (Aib). Although the helix length is shorter than the membrane thickness, the 11-residue peptaibol trichorovin-XII (TV-XII) can form ion channels in membranes. Assuming that a higher proportion of isoleucine (Ile) relative to leucine (Leu) residues is crucial for maintaining the ion channel activity of TV-XII, peptide analogs of TV-XII with varying Ile content were designed, synthesized, and evaluated. The secondary structure of all derivatives under hydrophobic conditions was confirmed by CD measurement as an α-helix-like ß-bend ribbon spiral structure. The most stable ion channel activity was found in compound 4a with maximum Ile. Furthermore, the C-terminal Ile analog showed greater ion channel activity compared to the Leu analog. This suggests that the choice between Leu and Ile can influence the expression of ion channel activity, which will be crucial for the de novo designed functional peptides.
Asunto(s)
Isoleucina , Peptaiboles , Isoleucina/química , Isoleucina/análogos & derivados , Peptaiboles/química , Peptaiboles/farmacología , Peptaiboles/síntesis química , Canales Iónicos/metabolismo , Canales Iónicos/química , Estructura Secundaria de Proteína , Relación Estructura-Actividad , Secuencia de Aminoácidos , Dicroismo CircularRESUMEN
Plant diseases caused by Pseudomonas syringae are essentially controlled in the field with the use of copper-based products and antibiotics, raising environmental and safety concerns. Antimicrobial peptides (AMPs) derived from fungi may represent a sustainable alternative to those chemicals. Trichogin GA IV, a non-ribosomal, 11-residue long AMP naturally produced by the fungus Trichoderma longibrachiatum has the ability to insert into phospholipidic membranes and form water-filled pores, thereby perturbing membrane integrity and permeability. In previous studies, peptide analogs modified at the level of specific residues were designed to be water-soluble and active against plant pathogens. Here, we studied the role of glycine-to-lysine substitutions and of the presence of a C-terminal leucine amide on bioactivity against Pseudomonas syringae bacteria. P. syringae diseases affect a wide range of crops worldwide, including tomato and kiwifruit. Our results show that trichogin GA IV analogs containing two or three Gly-to-Lys substitutions are highly effective in vitro against P. syringae pv. tomato (Pst), displaying minimal inhibitory and minimal bactericidal concentrations in the low micromolar range. The same analogs are also able to inhibit in vitro the kiwifruit pathogen P. syringae pv. actinidiae (Psa) biovar 3. When sprayed on tomato plants 24 h before Pst inoculation, only tri-lysine containing analogs were able to significantly reduce bacterial titers and symptom development in infected plants. Our results point to a positive correlation between the number of lysine substitutions and the antibacterial activity. This correlation was supported by microscopy analyses performed with mono-, di- and tri-Lys containing analogs that showed a different degree of interaction with Pst cells and ultrastructural changes that culminated in cell lysis.
Asunto(s)
Antibacterianos , Lisina , Pseudomonas syringae , Pseudomonas syringae/efectos de los fármacos , Lisina/química , Lisina/farmacología , Antibacterianos/farmacología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Peptaiboles/farmacología , Peptaiboles/química , Pruebas de Sensibilidad Microbiana , Oligopéptidos/farmacología , Oligopéptidos/química , Solanum lycopersicum/microbiologíaRESUMEN
Eco-friendly bioherbicides are urgently needed for managing the problematic weed Amaranthus retroflexus. A mass spectrometry- and bioassay-guided screening approach was employed to identify phytotoxic secondary metabolites from fungi for the development of such bioherbicides. This effort led to the discovery of six phytotoxic 16-residue peptaibols, including five new compounds (2-6) and a known congener (1), from Emericellopsis sp. XJ1056. Their planar structures were elucidated through the analysis of tandem mass and NMR spectroscopic data. The absolute configurations of the chiral amino acids were determined by advanced Marfey's method and chiral-phase liquid chromatography-mass spectrometry (LC-MS) analysis. Bioinformatic analysis and targeted gene disruption identified the biosynthetic gene cluster for these peptaibols. Compounds 1 and 2 significantly inhibited the radicle growth of A. retroflexus seedlings, and 1 demonstrated potent postemergence herbicidal activity against A. retroflexus while exhibiting minimal toxicity to Sorghum bicolor. Structure-activity relationship analysis underscored the importance of trans-4-hydroxy-l-prolines at both the 10th and 13th positions for the herbicidal activities of these peptaibols.
Asunto(s)
Herbicidas , Hypocreales , Peptaiboles/química , Peptaiboles/farmacología , Herbicidas/farmacología , Aminoácidos/metabolismo , Espectrometría de Masas , Hypocreales/metabolismoRESUMEN
Our previous study identified 52 antiplasmodial peptaibols isolated from fungi. To understand their antiplasmodial mechanism of action, we conducted phenotypic assays, assessed the in vitro evolution of resistance, and performed a transcriptome analysis of the most potent peptaibol, HZ NPDG-I. HZ NPDG-I and 2 additional peptaibols were compared for their killing action and stage dependency, each showing a loss of digestive vacuole (DV) content via ultrastructural analysis. HZ NPDG-I demonstrated a stepwise increase in DV pH, impaired DV membrane permeability, and the ability to form ion channels upon reconstitution in planar membranes. This compound showed no signs of cross resistance to targets of current clinical candidates, and 3 independent lines evolved to resist HZ NPDG-I acquired nonsynonymous changes in the P. falciparum multidrug resistance transporter, pfmdr1. Conditional knockdown of PfMDR1 showed varying effects to other peptaibol analogs, suggesting differing sensitivity.
Asunto(s)
Antimaláricos , Malaria Falciparum , Humanos , Peptaiboles/metabolismo , Peptaiboles/farmacología , Antimaláricos/farmacología , Proteínas de Transporte de Membrana , Permeabilidad de la Membrana CelularRESUMEN
From the fungus Trichoderma sp., we isolated seven novel 18-residue peptaibols, neoatroviridins E-K (1-7), and six new 14-residue peptaibols, harzianins NPDG J-O (8-13). Additionally, four previously characterized 18-residue peptaibols neoatroviridins A-D (14-17) were also identified. The structural configurations of the newly identified peptaibols (1-13) were determined by comprehensive nuclear magnetic resonance (NMR) and high-resolution electrospray ionization tandem mass spectrometry (HR-ESI-MS/MS) data. Their absolute configurations were further determined using Marfey's method. Notably, compounds 12 and 13 represent the first 14-residue peptaibols containing an acidic amino acid residue. In antimicrobial assessments, all 18-residue peptaibols (1-7, 14-17) exhibited moderate inhibitory activities against Staphylococcus aureus 209P, with minimum inhibitory concentration (MIC) values ranging from 8-32 µg·mL-1. Moreover, compound 9 exhibited moderate inhibitory effect on Candida albicans FIM709, with a MIC value of 16 µg·mL-1.
Asunto(s)
Antiinfecciosos , Trichoderma , Peptaiboles/farmacología , Peptaiboles/química , Trichoderma/química , Trichoderma/metabolismo , Espectrometría de Masas en Tándem/métodos , Antiinfecciosos/farmacología , Espectrometría de Masa por Ionización de Electrospray/métodosRESUMEN
Pseudodiploöspora longispora (previously known as Diploöspora longispora) is a pathogenic fungus of Morchella mushrooms. The molecular mechanism underlying the infection of P. longispora in fruiting bodies remains unknown. In this study, three known peptaibols, alamethicin F-50, polysporin B, and septocylindrin B (1-3), and a new analogue, longisporin A (4), were detected and identified in the culture of P. longispora and the fruiting bodies of M. sextelata infected by P. longispora. The primary amino sequence of longisporin A is defined as Ac-Aib1-Pro2-Aib3-Ala4-Aib5-Aib6-Gln7-Aib8-Val9-Aib10-Glu11-Leu12-Aib13-Pro14-Val15-Aib16-Aib17-Gln18-Gln19-Phaol20. The peptaibols 1-4 greatly suppressed the mycelial growth of M. sextelata. In addition, treatment with alamethicin F-50 produced damage on the cell wall and membrane of M. sextelata. Compounds 1-4 also exhibited inhibitory activities against human pathogens including Aspergillus fumigatus, Candida albicans, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus, and plant pathogen Verticillium dahlia. Herein, peptaibols are confirmed as virulence factors involved in the invasion of P. longispora on Morchella, providing insights into the interaction between pathogenic P. longispora and mushrooms.
Asunto(s)
Agaricales , Ascomicetos , Staphylococcus aureus Resistente a Meticilina , Humanos , Peptaiboles/farmacología , Candida albicans , Antibacterianos/farmacologíaRESUMEN
Peptaibols are proteolysis-resistant, membrane-active peptides. Their remarkably stable helical 3D-structures are key for their bioactivity. They can insert themselves into the lipid bilayer as barrel staves, or lay on its surface like carpets, depending on both their length and the thickness of the lipid bilayer. Medium-length peptaibols are of particular interest for studying the peptide-membrane interaction because their length allows them to adopt either orientation as a function of the membrane thickness, which, in turn, might even result in an enhanced selectivity. Electron paramagnetic resonance (EPR) is the election technique used to this aim, but it requires the synthesis of spin-labeled medium-length peptaibols, which, in turn, is hampered by the poor reactivity of the Cα-tetrasubstituted residues featured in their sequences. After several years of trial and error, we are now able to give state-of-the-art advice for a successful synthesis of nitroxide-containing peptaibols, avoiding deleted sequences, side reactions and difficult purification steps. Herein, we describe our strategy and itsapplication to the synthesis of spin-labeled analogs of the recently discovered, natural, medium-length peptaibol pentadecaibin. We studied the antitumor activity of pentadecaibin and its analogs, finding potent cytotoxicity against human triple-negative breast cancer and ovarian cancer. Finally, our analysis of the peptide conformational preferences and membrane interaction proved that pentadecaibinspin-labeling does not alter the biological features of the native sequence and is suitable for further EPR studies. The nitroxide-containing pentadecaibins, and their synthetic strategy described herein, will help to shed light on the mechanism of the peptide-membrane interaction of medium-length peptaibols.
Asunto(s)
Antiinfecciosos , Peptaiboles , Humanos , Peptaiboles/farmacología , Marcadores de Spin , Membrana Dobles de Lípidos , Antiinfecciosos/farmacologíaRESUMEN
In the large field of bioactive peptides, peptaibols represent a unique class of compounds. They are membrane-active peptides, produced by fungi of the genus Trichoderma and known to elicit plant defenses. Among the short-length peptaibols, trichogin GA IV is nonhemolytic, proteolysis-resistant, antibacterial, and cytotoxic. Several trichogin analogs are endowed with potent activity against phytopathogens, thus representing a sustainable alternative to copper for plant protection. In this work, we tested the activity of trichogin analogs against a breast cancer cell line and a normal cell line of the same derivation. Lys-containing trichogins showed an IC50 below 12 µM, a peptide concentration not significantly affecting the viability of normal cells. Two analogs were found to be membrane-active but noncytotoxic. They were anchored to gold nanoparticles (GNPs) and further investigated for their ability to act as targeting agents. GNP uptake by cancer cells increased with peptide decoration, while it decreased in the corresponding normal epithelial cells. This work highlights the promising biological properties of peptaibol analogs in the field of cancer therapy either as cytotoxic molecules or as active targeting agents in drug delivery.
Asunto(s)
Hypocreales , Nanopartículas del Metal , Trichoderma , Oro/farmacología , Oro/metabolismo , Peptaiboles/farmacología , Peptaiboles/metabolismo , Hypocreales/metabolismo , Trichoderma/metabolismoRESUMEN
Plasmopara viticola, the agent of grapevine downy mildew, causes enormous economic damage, and its control is primarily based on the use of synthetic fungicides. The European Union policies promote reducing reliance on synthetic plant protection products. Biocontrol agents such as Trichoderma spp. constitute a resource for the development of biopesticides. Trichoderma spp. produce secondary metabolites such as peptaibols, but the poor water solubility of peptaibols limits their practical use as agrochemicals. To identify new potential bio-inspired molecules effective against P. viticola, various water-soluble peptide analogs of the peptaibol trichogin were synthesized. In grapevine leaf disk assays, the peptides analogs at a concentration of 50 µM completely prevented P. viticola infection after zoosporangia inoculation. Microscopic observations of one of the most effective peptides showed that it causes membrane lysis and cytoplasmic granulation in both zoosporangia and zoospores. Among the effective peptides, 4r was selected for a 2-year field trial experiment. In the vineyard, the peptide administered at 100 µM (equivalent to 129.3 g/ha) significantly reduced the disease incidence and severity on both leaves and bunches, with protection levels similar to those obtained using a cupric fungicide. In the second-year field trial, reduced dosages of the peptide were also tested, and even at the peptide concentration reduced by 50 or 75%, a significant decrease in the disease incidence and severity was obtained at the end of the trial. The peptide did not show any phytotoxic effect. Previously, peptide 4r had been demonstrated to be active against other fungal pathogens, including the grapevine fungus Botrytis cinerea. Thus, this peptide may be a candidate for a broad-spectrum fungicide whose biological properties deserve further investigation.
Asunto(s)
Oomicetos , Peronospora , Trichoderma , Vitis , Peptaiboles/metabolismo , Peptaiboles/farmacología , Granjas , Vitis/microbiología , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología , AguaRESUMEN
Total 23 eleven-residue peptaibols, including five reported ones (1-5) in our previous work, were isolated from the fungus Trichoderma longibrachiatum Rifai DMG-3-1-1, which was obtained from the mushroom Clitocybe nebularis (Batsch) P. Kumm. The structures of the 13 new peptaibols (6-10 and 12-19) were determined by their NMR and MALDI-MS/MS data, their absolute structures were further determined by Marfey's analyses and their ECD data. Careful comparison of the structures of 1-23 showed that only seven residues varied including the 2nd (Gln2 /Asn2 ), 3rd (Ile3 /Val3 ), 4th (Ile4 /Val4 ), 6th (Pro6 /Hyp6 ), 8th (Leu8 /Val8 ), 10th (Pro10 /Hyp10 ) and 11th (Leuol11 /Ileol11 /Valol11 ) residues. Comparison of the IC50 s against the three tested cell lines of 1-23 indicated that 2nd, 3rd and 4th amino acid residues affected their cytotoxicities powerfully. Compounds 2, 5, 9, 11, 21 and 22 showed moderate antibacterial activities against Staphylococcus aureus MRSA T144, which also showed stronger cytotoxicities against BV2 and MCF-7 cells.
Asunto(s)
Peptaiboles , Trichoderma , Aminoácidos/metabolismo , Antibacterianos/química , Hypocreales , Peptaiboles/química , Peptaiboles/farmacología , Relación Estructura-Actividad , Espectrometría de Masas en Tándem , Trichoderma/químicaRESUMEN
Seven new peptaibols named tolypocladamides A-G have been isolated from an extract of the fungus Tolypocladium inflatum, which inhibits the interaction between Raf and oncogenic Ras in a cell-based high-throughput screening assay. Each peptaibol contains 11 amino acid residues, an octanoyl or decanoyl fatty acid chain at the N-terminus, and a leucinol moiety at the C-terminus. The peptaibol sequences were elucidated on the basis of 2D NMR and mass spectral fragmentation analyses. Amino acid configurations were determined by advanced Marfey's analyses. Tolypocladamides A-G caused significant inhibition of Ras/Raf interactions with IC50 values ranging from 0.5 to 5.0 µM in a nanobioluminescence resonance energy transfer (NanoBRET) assay; however, no interactions were observed in a surface plasmon resonance assay for binding of the compounds to wild type or G12D mutant Ras constructs or to the Ras binding domain of Raf. NCI 60 cell line testing was also conducted, and little panel selectivity was observed.
Asunto(s)
Antineoplásicos , Hypocreales , Aminoácidos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Hypocreales/química , Peptaiboles/farmacologíaRESUMEN
Longibrachiamide A (1), a new 20-residue peptaibol, along with three known ones (2-4), were isolated from the fungus Trichoderma longibrachiatum Rifai DMG-3-1-1, isolated from a mushroom Clitocybe nebularis (Batsch) P. Kumm, which was collected from coniferous forest of northeast China in our previous work. The structure of longibrachiamide A (1) was determined by its NMR and ESI-MS/MS data, the absolute configuration of 1 was further determined by Marfey's analyses. And the complete NMR data of 2-4 were also reported for the first time. The similar CD spectra of 1-4 showed that they all had mixed 310 -/α-helical conformations. Compounds 1-4 showed strong cytotoxicities against BV2, A549 and MCF-7 cells, and also showed moderate inhibitory effects against the tested Gram-positive bacteria, including MRSA T144 and VRE-10.
Asunto(s)
Hypocreales , Trichoderma , Peptaiboles/química , Peptaiboles/farmacología , Espectrometría de Masas en Tándem , Trichoderma/químicaRESUMEN
Fungal species of genus Sepedonium are rich sources of diverse secondary metabolites (e.g., alkaloids, peptaibols), which exhibit variable biological activities. Herein, two new peptaibols, named ampullosporin F (1) and ampullosporin G (2), together with five known compounds, ampullosporin A (3), peptaibolin (4), chrysosporide (5), c(Trp-Ser) (6) and c(Trp-Ala) (7), have been isolated from the culture of Sepedonium ampullosporum Damon strain KSH534. The structures of 1 and 2 were elucidated based on ESI-HRMSn experiments and intense 1D and 2D NMR analyses. The sequence of ampullosporin F (1) was determined to be Ac-Trp1-Ala2-Aib3-Aib4-Leu5-Aib6-Gln7-Aib8-Aib9-Aib10-GluOMe11-Leu12-Aib13-Gln14-Leuol15, while ampullosporin G (2) differs from 1 by exchanging the position of Gln7 with GluOMe11. Furthermore, the total synthesis of 1 and 2 was carried out on solid-phase to confirm the absolute configuration of all chiral amino acids as L. In addition, ampullosporin F (1) and G (2) showed significant antifungal activity against B. cinerea and P. infestans, but were inactive against S. tritici. Cell viability assays using human prostate (PC-3) and colorectal (HT-29) cancer cells confirmed potent anticancer activities of 1 and 2. Furthermore, a molecular docking study was performed in silico as an attempt to explain the structure-activity correlation of the characteristic ampullosporins (1-3).
Asunto(s)
Antifúngicos/farmacología , Antineoplásicos/farmacología , Ésteres/química , Ácido Glutámico/química , Hypocreales/fisiología , Neoplasias/tratamiento farmacológico , Peptaiboles/farmacología , Ascomicetos/efectos de los fármacos , Botrytis/efectos de los fármacos , Humanos , Neoplasias/patología , Peptaiboles/química , Phytophthora infestans/efectos de los fármacos , Células Tumorales CultivadasRESUMEN
Six new 16-residue peptaibols, acremopeptaibols A-F (1-6), along with five known compounds, were isolated from the cultures of the sponge-associated fungus Acremonium sp. IMB18-086 grown in the presence of the autoclaved bacterium Pseudomonas aeruginosa on solid rice medium. The peptaibol sequences were established based on comprehensive analysis of 1D and 2D NMR spectroscopic data in conjunction with HRESIMS/MS experiments. The configurations of the amino acid residues were determined by advanced Marfey's analysis. Compounds 1-6 feature the lack of the highly conserved Thr6 and Hyp10 residues in comparison with other members of the SF3 subfamily peptaibols. A plausible biosynthetic pathway of compounds 1-6 was proposed on the basis of genomic analysis. Compounds 1, 5, 7, and 10 exhibited significant antimicrobial activity against Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Candida albicans. Compounds 7-10 showed potent cytotoxicities against the A549 and/or HepG2 cancer cell lines.
Asunto(s)
Acremonium/metabolismo , Peptaiboles/aislamiento & purificación , Poríferos/microbiología , Pseudomonas aeruginosa/metabolismo , Células A549 , Animales , Vías Biosintéticas , Células Hep G2 , Humanos , Peptaiboles/química , Peptaiboles/farmacologíaRESUMEN
Fighting resistance to antibiotics and chemotherapeutics has brought bioactive peptides to the fore. Peptaibols are short α-aminoisobutyric acid-containing peptides produced by Trichoderma species. Here, we studied the production of peptaibols by Trichoderma atroviride O1 and evaluated their antibacterial and anticancer activity against drug-sensitive and multidrug-resistant bacterium and cancer cell lines. This was substantiated by an analysis of the activity of the peptaibol synthetase-encoding gene. Atroviridins, 20-residue peptaibols were detected using MALDI-TOF mass spectrometry. Gram-positive bacteria were susceptible to peptaibol-containing extracts of T. atroviride O1. A synergic effect of extract constituents was possible, and the biolo-gical activity of extracts was pronounced in/after the peak of peptaibol synthetase activity. The growth of methicillin-resistant Staphylococcus aureus was reduced to just under 10% compared to the control. The effect of peptaibol-containing extracts was strongly modulated by the lipoteichoic acid and only slightly by the horse blood serum present in the cultivation medium. Peptaibol-containing extracts affected the proliferation of human breast cancer and human ovarian cancer cell lines in a 2D model, including the multidrug-resistant sublines. The peptaibols influenced the size and compactness of the cell lines in a 3D model. Our findings indicate the molecular basis of peptaibol production in T. atroviride O1 and the potential of its peptaibol-containing extracts as antimicrobial/anticancer agents.
Asunto(s)
Farmacorresistencia Bacteriana , Hypocreales/metabolismo , Ligasas/metabolismo , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Peptaiboles/farmacología , Animales , Antibacterianos/farmacología , Antineoplásicos/farmacología , Línea Celular Tumoral , Femenino , Proteínas Fúngicas/metabolismo , Caballos , Humanos , Hypocreales/enzimología , Células MCF-7 , Peptaiboles/análisis , Peptaiboles/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Peptaibols, by disturbing the permeability of phospholipid membranes, can overcome anticancer drug resistance, but their natural hydrophobicity hampers their administration. By a green peptide synthesis protocol, we produced two water-soluble analogs of the peptaibol trichogin GA IV, termed K6-Lol and K6-NH2. To reduce production costs, we successfully explored the possibility of changing the naturally occurring 1,2-aminoalcohol leucinol to a C-terminal amide. Peptaibol activity was evaluated in ovarian cancer (OvCa) and Hodgkin lymphoma (HL) cell lines. Peptaibols exerted comparable cytotoxic effects in cancer cell lines that were sensitive-and had acquired resistance-to cisplatin and doxorubicin, as well as in the extrinsic-drug-resistant OvCa 3-dimensional spheroids. Peptaibols, rapidly taken up by tumor cells, deeply penetrated and killed OvCa-spheroids. They led to cell membrane permeabilization and phosphatidylserine exposure and were taken up faster by cancer cells than normal cells. They were resistant to proteolysis and maintained a stable helical structure in the presence of cancer cells. In conclusion, these promising results strongly point out the need for further preclinical evaluation of our peptaibols as new anticancer agents.
Asunto(s)
Antineoplásicos/farmacología , Cisplatino/farmacología , Doxorrubicina/farmacología , Enfermedad de Hodgkin/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Peptaiboles/farmacología , Antineoplásicos/química , Resistencia a Antineoplásicos , Femenino , Enfermedad de Hodgkin/patología , Humanos , Neoplasias Ováricas/patología , Peptaiboles/química , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/patología , Células Tumorales CultivadasRESUMEN
A new 11 amino acid linear peptide named roseabol A (1) and the known compound 13-oxo-trans-9,10-epoxy-11(E)-octadecenoic acid (2) were isolated from the fungus Clonostachys rosea. Combined NMR and MS analysis revealed that roseabol A (1) contained amino acid residues characteristic of the peptaibol family of peptides such as isovaline, α-aminoisobutyric acid, hydroxyproline, leucinol, and an N-terminal isovaleric acid moiety. The amino acid sequence was established by a combination of NMR studies and tandem MS fragmentation analyses, and the absolute configurations of the constituent amino acids of 1 were determined by the advanced Marfey's method. Compound 2 showed inhibitory activity against Merkel cell carcinoma, a rare and difficult-to-treat type of skin cancer, with an IC50 value of 16.5 µM.
Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Células de Merkel/tratamiento farmacológico , Hypocreales/química , Peptaiboles/química , Peptaiboles/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Secuencia de Aminoácidos , Antineoplásicos/química , Carcinoma de Células de Merkel/química , Carcinoma de Células de Merkel/metabolismo , Línea Celular Tumoral , Humanos , Espectroscopía de Resonancia Magnética/métodos , Estructura Molecular , Neoplasias Cutáneas/química , Neoplasias Cutáneas/metabolismoRESUMEN
Five new peptaibols, longibramides A-E (1-5) with 11 amino acid residues, were isolated from a fungus Trichoderma longibrachiatum Rifai DMG-3-1-1, which was isolated from a mushroom Clitocybe nebularis (Batsch) P. Kumm collected from coniferous forest in the subboreal area of northeast China. The structures of longibramides A-E were determined by their spectroscopic data (NMR and MS-MS spectra), their absolute configurations were determined by X-ray diffractions and Marfey's analyses. The X-ray diffractions of longibramides A, B, and the similar CD spectra of A-E showed that they all had α-helix conformations. Longibramides B and E showed moderate cytotoxicities against BV2 and MCF-7 cells and also showed some inhibitory effects against methicillin-resistant Staphylococcus aureus MRSA T144. L-trans-Hyp was not commonly found in natural peptaibols, which was the 6th or 10th amino acid residue in longibramides C-E. The X-ray diffractions of longibramides A and B afforded the accuracy conformations of their secondary structures, which maybe help to interpret the structure-activity relationships of the family of peptaibols in the future.