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Różnicowanie C. albicans i C. dubliniensis w oparciu o polimorfizm genu syntazy homocytrynianowej z wykorzystaniem metody PCR RFLP
PublicationNajczęstszym czynnikiem etiologicznym zakażeń wywołanych przez drożdżaki z rodzaju Candida jest C. albicans. Gatunek ten posiada bardzo zbliżone cechy fenotypowe do C. dubliniensis co często wiąże się z błędną identyfikacją. Skutkuje to wtórnym zakażeniem wywołanym przez współwystepujący gatunek C. dubliniensis, który nabywa oporność na flikonazol stosowany w terapii C. albicans. Celem badań była konstrukcja układu diagnostycznego...
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Phenotypic consequences of the LYS4 gene disruption in Candida albicans
PublicationThe main scientific purpose of our studies was to verify the hypothesis that homoaconitase (HA) from Candida albicans, an enzyme catalyzing a second step of the α-aminoadipate pathway (AAP) of L-Lys biosynthesis may become a new target for antifungal chemotherapy. Previous studies indicated that the A. fumigatus mutant lacking the functional lysF gene, encoding HA, exhibited attenuated virulence in a low-dose mouse infection model...
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Voriconazole and multidrug resistance in Candida albicans
PublicationPorównano aktywność grzybostatyczną in vitro worikonazolu, flukonazolu, ketokonazolu i klotrimazolu wobec opornych na flukonazol szczepów klinicznych Candida albicans oraz rekombinowanych szczepów Saccharomyces cerevisiae eksprymujących jeden z genów kodujących białka oporności wielolekowej (MDR) C. albicans: Cdr1p. Cdr2p lub CaMdr1p. Stwierdzono, że nadekspresja genów MDR czyni komórki drożdżaków mniej wrażliwymi na działanie...
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Characterization of two aminotransferases from Candida albicans
PublicationAminoadipate aminotransferase (AmAA) is an enzyme of α-aminoadipate pathway (AAP) for l-lysine biosynthesis. AmAA may also participated in biosynthesis or degradation of aromatic amino acids and in d-tryptophan based pigment production. The AAP is unique for fungal microorganisms. Enzymes involved in this pathway have specific structures and properties. These features can be used as potential molecular markers. Enzymes catalyzing...
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SKUTECZNOŚĆ DZIAŁANIA 5-FLUOROCYTOZYNY W STOSUNKU DO KLINICZNYCH IZOLATÓW CANDIDA ALBICANS I CANDIDA GLABRATA OPORNYCH NA FLUKONAZOL
PublicationCelem prowadzonych badań było sprawdzenie skuteczność działania 5-fluorocytozyny (5-FC) w stosunku do klinicznych izolatów C. albicans i C. glabrata wyizolowanych od pacjentów z trzech polskich szpitali. W przebadanej populacji wszystkie przebadane szczepy C. albicans były wrażliwe na działanie 5-FC, natomiast w przypadku gatunku C. glabrata wystąpiły 3 szczepy oporne i 4 średniooporne. Zjawisko nabywania lekooporności jest coraz...
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Removal of cyclohexane and ethanol from air in biotrickling filters inoculated with Candida albicans and Candida subhashii
PublicationThis paper presents investigations on the removal of cyclohexane and ethanol from air in polyurethane- -packed biotrickling filters, inoculated with Candida albicans and Candida subhashii fungal species. Results on process performance together with flow cytometry analyses of the biofilm formed over packing elements are presented and discussed. The results indicate that the presence of ethanol enhances the removal efficiency of cyclohexane...
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Phenotypic consequences of LYS4 gene disruption in Candida albicans
PublicationA BLAST search of the Candida Genome Database with the Saccharomyces cerevisiae LYS4 sequence known to encode homoaconitase (HA) revealed ORFs 19.3846 and 19.11327. Both alleles of the LYS4 gene were sequentially disrupted in Candida albicans BWP17 cells using PCR-based methodology. The null lys4Δ mutant exhibited lysine auxotrophy in minimal medium but was able to grow in the presence of L-Lys and α-aminoadipate, an intermediate...
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Characterization of recombinant homocitrate synthase from Candida albicans
PublicationLYS21 and LYS22 genes from Candida albicans encoding isoforms of homocitrate synthase (HCS), an enzyme catalyzing the first committed step in the L-lysine biosynthetic pathway, were cloned and expressed as NoligoHistagged fusion proteins in Escherichia coli. The purified gene products revealed HCS activity, i.e. catalyzed the condensation of α-ketoglutarate with acetyl-coenzyme A to yield homocitrate. The recombinant enzymes were purified...
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KONSTRUKCJA AUKSOTROFICZNEGO WZGLĘDEM L-LIZYNY SZCZEPU CANDIDA ALBICANS
PublicationEnzymy szlaku kwasu L-α-aminoadypinowego biosyntezy L-lizyny z Candida albicans są potencjalnymi celami molekularnymi w terapii przeciwgrzybowej. Niektóre grupy badawcze wykazały, że auksotrofia wobec L-lizyny u pewnych gatunków grzybów powoduje zmniejszenie ich zjadliwości i może mieć wpływ na wzrost in vivo [Liebmann i in. 2004]. Oznacza to, że można się spodziewać zahamowania wzrostu komórek grzybowych w wyniku działania selektywnych...
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Method-Dependent Epidemiological Cutoff Values for Detection of Triazole Resistance in Candida and Aspergillus Species for the Sensititre YeastOne Colorimetric Broth and Etest Agar Diffusion Methods
PublicationAlthough the Sensititre Yeast-One (SYO) and Etest methods are widely utilized, interpretive criteria are not available for triazole susceptibility testing of Candida or Aspergillus species. We collected fluconazole, itraconazole, posaconazole, and voriconazole SYO and Etest MICs from 39 laboratories representing all continents for (method/agent-dependent) 11,171 Candida albicans, 215 C. dubliniensis, 4,418 C. glabrata species complex,...
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Versatility of putative aromatic aminotransferases from Candida albicans.
PublicationAmino acids constitute the key sources of nitrogen for growth of Candida albicans. In order to survive inside the host in different and rapidly changing environments, this fungus must be able to adapt via its expression of genes for amino acid metabolism. We analysed the ARO8, ARO9, YER152C, and BNA3 genes with regards to their role in the nutritional flexibility of C. albicans. CaAro8p is undoubtedly the most versatile enzyme...
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Novel Nystatin A1 derivatives exhibiting low host cell toxicity and antifungal activity in an in vitro model of oral candidosis
PublicationOpportunistic oral infections caused by Candida albicans are frequent problems in immunocompromised patients. Management of such infections is limited due to the low number of antifungal drugs available, their relatively high toxicity and the emergence of antifungal resistance. Given these issues, our investigations have focused on novel derivatives of the antifungal antibiotic Nystatin A1, generated by modifications at the amino...
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Essential Oils, Silver Nanoparticles and Propolis as Alternative Agents Against Fluconazole Resistant Candida albicans, Candida glabrata and Candida krusei Clinical Isolates
PublicationDevelopment of effective and safe therapeutic treatment of fungal infections remains one of the major challenge for modern medicine. The aim of presented investigation was to analyze the in vitro antifungal activity of selected essential oils, ethanolic extracts of propolis and silver nanoparticles dropped on TiO2 against azole-resistant C. albicans (n = 20), C. glabrata (n = 14) and C. krusei (n = 10) clinical isolates. Among...
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Voriconazole-Based Salts Are Active against Multidrug-Resistant Human Pathogenic Yeasts
PublicationVoriconazole (VOR) hydrochloride is unequivocally converted into VOR lactates and valinates upon reaction with silver salts of organic acids. This study found that the anticandidal in vitro activity of these compounds was comparable or slightly better than that of VOR. The Candida albicans clinical isolate overexpressing CaCDR1/CaCDR2 genes, highly resistant to VOR, was apparently more susceptible to VOR salts. On the other hand,...
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Molecular Umbrella as A Nanocarrier for Antifungals
PublicationA molecular umbrella composed of two O‐sulfated cholic acid residues was applied for the construction of conjugates with cispentacin, containing a “trimethyl lock” (TML) or o‐dithiobenzylcarbamoyl moiety as a cleavable linker. Three out of five conjugates demonstrated antifungal in vitro activity against C. albicans and C. glabrata but not against C. krusei, with MIC90 values in the 0.22–0.99 mM range and were not hemolytic. Antifungal...
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WIELOLEKOOPORNE ZAKAŻENIA CANDIDA - PROBLEM XXI WIEKU!
PublicationW ostatnich latach obserwuje się dramatyczny wzrost zakażeń grzybiczych, których przyczyną są grzyby z rodzaju Candida (C). Większość zakażeń wywoływana jest przez C. albicans, C. glabrata, C. krusei, C. parapsilosis i C. tropicalis. Dotychczas najczęściej stosowanymi lekami przeciwko Candida spp były azole, jednakże ze względu na występowanie naturalnej oporności na te antybiotyki (C. glabrata i C. krusei) coraz częściej azole...
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Genotyping of clinical isolates of fluconazole-resistant Candida albicans
PublicationThe aim of the study was to compare the discriminatory power of RAPD-PCR method with using RSD10 primer and microsatellite analysis with using (GACA)4 primer for genotyping clinical isolates of fluconazole-resistant C. albicans. Isolates were received from patients of Children's Memorial Health Institute in Warsaw. However in the case of both tested methods low number of amplified fragments was generated, nine and six different...
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Antifungal Activity and Synergism with Azoles of Polish Propolis
PublicationThe aim of our work was to check if one of the products of natural origin, namely honey 19 bee propolis may be an alternative or supplement to currently used antifungal agents. The activity 20 of 50 ethanolic extracts of propolis (EEPs), harvested in Polish apiaries, was tested on a group of 69 21 clinical isolates of C. albicans. Most of the EEPs showed satisfactory activity, with minimum 22 fungicidal concentrations (MFC) mainly...
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ABC transporters Cdr1p, Cdr2p and Cdr3p of a human pathogen Candida albicans are general phospholipid translocators
PublicationFluoryzujące analogi fosfolipidów NBD-PE, NBD-PC i NBD-PS zostały wykorzystane w celu wykazania, że białko Cdr1p i jego inne homologi, Cdr2p i Cdr3p, należące do grupy białek zawierających tzw. kasetę wiążącą ATP (ABC), zachowują się jak ogólne przenośniki lipidów. Wyniki badań pokazują, że transportery typu ABC występujące w C. albicans są przenośnikami fosfolipidów i aktywność ta może być jedna z fizjologicznych funkcji białek.
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Regulacja aktywności syntazy glukozamino-6-fosforanu z Candida albicans – badania metodami obliczeniowymi
PublicationNiniejsza praca przedstawia wyniki badań, prowadzonych metodami obliczeniowymi, poświęconych enzymowi syntazie GlcN-6-P pochodzącemu z drożdży C. albicans. Enzym ten odpowiedzialny jest między innymi za biosyntezę kluczowych składników ściany komórkowej grzybów i bakterii, ma również wpływ na regulację metabolizmu glukozy. Przedstawione badania stanowią jeden z etapów poszukiwania molekularnego mechanizmu inhibicji, której eukariotyczna...
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Mechanisms of azole resistance among clinical isolates of Candida glabrata in Poland
PublicationCandida glabrata is currently ranked as the second most frequently isolated aetiological agent of human fungal infections, next only to Candida albicans. In comparison with C. albicans, C. glabrata shows lower susceptibility to azoles, the most common agents used in treatment of fungal infections. Interestingly, the mechanisms of resistance to azole agents in C. albicans have been much better investigated than those in C. glabrata....
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Functional domains of Candida albicans glucosamine-6-phosphate synthase.
PublicationSkonstruowano oddzielnie dwie domeny syntazy GlcN-6-P z Candida albicans jako białka fuzyjne, tj. domenę glutaminazową oraz domenę izomerazową, zawierające sekwencje poliHis, odpowiednio na C- i N-końcu. Zoptymalizowano warunki nadekspresji domen w komórkach Escherichia coli. Oba białka oczyszczono do homogenności przy zastosowaniu chromatografii metalopowinowactwa oraz zbadano ich podstawowe właściwości. Wyznaczono parametry kinetyczne...
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Enzymy o aktywności aminotransferazy kwasu L-α-aminoadypinowego z Candida albicans - właściwości i rola w metabolizmie komórki grzybowej
PublicationCandida albicans jest elementem naturalnej flory drobnoustrojowej człowieka. Podobieństwo komórek grzybowych i ssaczych, wzrost częstości występowania infekcji grzybiczych wraz ze stopniowym wzrostem pojawiania się oporności patogenów stwarza potrzebę poszukiwania nowych związków przeciwgrzybowych. Jedną z dróg obraną przez naukowców jest analiza szlaków biosyntezy aminokwasów egzogennych dla człowieka. Przedmiotem badań w ramach...
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Peptide Permeases in Candida albicans
PublicationAims: The aim of this work was to characterize oligopeptide uptake in Candida albicans mutants in which the genes encoding putative peptide permeases were selectively disrupted. Initial velocities of transport of model oligopeptides, (Ala)2, (Ala)3, (Ala)4, and sensitivity of mutants to antifungal oligopeptides containing N3-(4-methoxyfumaroyl)-L-2,3-diaminopropanoic acid (FMDP) were determined and compared to those of the wild-type...
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Transport deficiency is the molecular basis of Candida albicans resistance to antifungal oligopeptides
Publication(FMDP), an inhibitor of glucosamine-6-phosphate synthase, exhibited growth inhibitory activity against Candida albicans, with minimal inhibitory concentration values in the 0.05–50 mg/L range. Uptake by the peptide permeases was found to be the main factor limiting an anticandidal activity of these compounds. Di- and tripeptide containing FMDP (F2 and F3) were transported by Ptr2p/Ptr22p peptide transporters (PTR) and FMDP-containing...
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Investigation of the Antifungal Activity and Mode of Action of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimum basilicum, and Eugenia caryophyllus Essential Oils
PublicationThe antimicrobial activity of plant oils and extracts has been recognized for many years. In this study the activity of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimumbasilicum, and Eugenia caryophyllus essential oils (EOs) distributed by Pollena Aroma (Nowy Dwór Mazowiecki, Poland) was investigated against a group of 183 clinical isolates of C. albicans and 76 isolates of C. glabrata. All of...
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Aktywność przeciwgrzybowa koniugatów inhibitorów enzymatycznych z nośnikami peptydowymi
PublicationCelem badań przedstawionych w rozprawie było określenie aktywności przeciwgrzybowej szeregu związków będących koniugatami peptydów z inhibitorami enzymatycznymi (FMDP, cispentacyna). Zakres badań obejmował zbadanie aktywności peptydów-FMDP, CPP oraz FMDP-CPP wobec grzybów z rodzaju Candida w różnego typu podłożach, określenie możliwości powstawania oporności na FMDP-CPP i peptydy-FMDP, a także określenie szybkości transportu i...
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A new 1-nitro-9-aminoacridine derivative targeting yeast topoisomerase II able to overcome fluconazole-resistance
PublicationFungal resistance remains a significant threat and a leading cause of death worldwide. Thus, overcoming microbial infections have again become a serious clinical problem. Although acridine derivatives are widely analyzed as anticancer agents, only a few reports have demonstrated their antifungal activity. In an effort to develop biologically active antifungals, twelve novel C-857 (9-(2′ -hydroxyethylamino)-1-nitroacridine) and...
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A novel in vitro assay for assessing efficacy and toxicity of antifungals using human leukaemic cells infected with Candida albicans
PublicationAims: This study describes a novel in vitro assay that simultaneously determines antifungal efficiency and host cell toxicity using suspensions of human leukaemic cells (HL-60) infected with Candida albicans. Methods and Results: The effect of Candida infection on host cell viability was evaluated by the microscopy of trypan blue-stained cells and lactate dehydrogenase (LDH) activity. The in vitro ‘drug potency assay’ utilized...
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Modification of quaternary structure of Candida albicans GlcN-6-P synthase and its desensitization to inhibition by UDP-GlcNAc by site-directed mutagenesis
PublicationSite-directed mutagenesis of the CaGFA1 gene encoding glucosamine-6-phosphate synthase from Candida albicans was performed. Desensitization of the enzyme to inhibition by UDPGlcNAc was achieved upon T487I and H492F substitutions at the UDP-GlcNAc binding site, exchange of D524, S525 and S527 for Ala at the dimer:dimer interface and construction of the tail-lock array (L434R and L460A) at the C-tail region. The first two sets if...
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Crystallization and preliminary X-ray analysis of the isomerase domain of glucosamine-6-phosphate synthase from Candida albicans
PublicationSyntaza glukozamino-6-fosforanu (EC 2.6.1.16) katalizuje pierwszy, praktycznie nieodwracalny etap w szlaku biosyntezy heksozoamin, którego produktem końcowym jest UDP-GlcNAc, kluczowy substrat dla tworzenia ściany komórkowej drobnoustrojów. Otrzymano kryształy domeny izomerazowej syntazy GlcN-6-P z Candida albicans, składającej się z reszt 346-712 (42 kDa). Analiza rentgenograficzna kryształu wykazała, że należy on do grupy przestrzennej...
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Enzymes of the lysine biosynthetic pathway as targets for antifungals ?
PublicationSystemic infections caused by human pathogenic fungi in immunocompromized patients continue to be one of the important clinical problems. Limited availability of safe and efficacious antifungal chemotherapeutics and emerging resistance to existing drugs stimulates search for novel molecular targets for antifungals. The α-aminoadipate pathway (AAP) of L-lysine biosynthesis is unique in fungi and thus has been so far considered...
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Virulence, antifungal susceptibility and molecular mechanisms of echinocandin resistance among Candida isolates recovered from clinical specimens
PublicationFungi of the genus Candida belong to the natural microflora of healthy individuals. However, they can also be a cause of opportunistic infections especially among patients with an impaired immune system. The first line therapy of Candida infections is based on triazoles. However, in recent years there an increase of azole resistant Candida spp., in particular C. glabrata and C. krusei, has been observed. For this reason, echinocandin...
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Crystal structures of aminotransferases Aro8 and Aro9 from Candida albicans and structural insights into their properties
PublicationAminotransferases catalyze reversibly the transamination reaction by a ping-pong bi-bi mechanism with pyridoxal 5′-phosphate (PLP) as a cofactor. Various aminotransferases acting on a range of substrates have been reported. Aromatic transaminases are able to catalyze the transamination reaction with both aromatic and acidic substrates. Two aminotransferases from C. albicans, Aro8p and Aro9p, have been identified recently, exhibiting...
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Molecular Targets for Anticandidal Chemotherapy
PublicationA relatively small number of anticandidal chemotherapeutics used in clinical practice is at least in part consequence of a limited number of their molecular targets: ergosterol in the membrane, lanosterol demethylase, b(1!3) glucan synthase, and DNA/RNA biosynthesis. Much more potential novel targets have been revealed by the comparative genomic studies identifying essential genes unique for Candida albicans or resulted from recognition...
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Aktywność biologiczna i selektywna toksyczność nowej klasy N-podstawionych pochodnych antybiotyku polienowego Nystatyny A1
PublicationCelem badań, których wyniki zaprezentowano w niniejszej pracy było określenie aktywności biologicznej nowej klasy N–podstawionych pochodnych Nystatyny A1 w stosunku do komórek grzybowych z rodzaju i ssaczych oraz ustalenie wpływu modyfikacji chemicznej na selektywną toksyczność tych związków. W toku wieloletnich prac badawczych zaproponowano, że wprowadzenie podstawnika na grupie aminowej cząsteczki antybiotyku o charakterze objętościowym...
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AKTYWNOŚĆ BIOLOGICZNA I SELEKTYWNA TOKSYCZNOŚĆ NOWEJ KLASY N–PODSTAWIONYCH POCHODNYCH ANTYBIOTYKU POLIENOWEGO NYSTATYNY A1
PublicationCelem badań, których wyniki zaprezentowano w niniejszej pracy było określenie aktywności biologicznej nowej klasy N–podstawionych pochodnych Nystatyny A1 w stosunku do komórek grzybowych z rodzaju i ssaczych oraz ustalenie wpływu modyfikacji chemicznej na selektywną toksyczność tych związków. W toku wieloletnich prac badawczych zaproponowano, że wprowadzenie podstawnika na grupie aminowej cząsteczki antybiotyku o charakterze objętościowym...
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New Peptide Based Fluconazole Conjugates with Expanded Molecular Targets
PublicationInfections of Candida spp. etiology are frequently treated with azole drugs. Among azoles, the most widely used in the clinical scenario remains fluconazole (FLC). Promising results in treatment of dangerous, systemic Candida infections demonstrate the advantages of combined therapies carried out with combinations of at least two different antifungal agents. Here, we report five conjugates composed of covalently linked FLC and...
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Glucosamine-6-phosphate synthase with an oligoHis insert
PublicationGlucosamine-6-phosphate (GlcN-6-P) synthase known also as L-Glutamine: D-fructose-6-phosphate aminotransferase (EC 2.6.1.16), catalyzes the first committed step in the amino sugar biosynthetic pathway in prokaryotic and eukaryotic organisms. The final product of this pathway is an activated precursor of numerous macromolecules containing amino sugars, including chitin and mannproteins in fungi, peptydoglican and lipopolysaccharides...
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Investigation of an elutable N-propylphosphonic acid chitosan derivative composition with a chitosan matrix prepared from carbonic acid solution
PublicationPorous chitosan composites using CO2 dissolution procedure and including water soluble N-propylphosphonic chitosan derivative (p-CHI) were obtained and characterized. In contrast to the control material, composites containing modified chitosan distinguished by a rapid moisture absorption and good adhesion to the skin. The FTIR analysis confirmed the presence of propylphosphonic group in the structure of the polymer. The porosity...
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Emerging anticancer activity of candidal glucoseamine-6-phosphate synthase inhibitors upon nanoparticle-mediated delivery
PublicationNumerous glutamine analogues have been reported as irreversible inhibitors of the glucosamine-6-phosphate (GlcN-6-P) synthase in pathogenic Candida albicans in the last 3.5 decades. Among the reported inhibitors, the most effective N3-(4-methoxyfumaroyl)-L-2,3- diaminopropanoic acid (FMDP) has been extensively studied in order to develop its more active analogues. Several peptide−FMDP conjugates were tested to deliver FMDP to its...
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The novel sterilization device: the prototype testing
PublicationCurrently, there are numerous methods that can be used to neutralize pathogens (i.e., devices, tools, or protective clothing), but the sterilizing agent must be selected so that it does not damage or change the properties of the material to which it is applied. Dry sterilization with hydrogen peroxide gas (VHP) in combination with UV-C radiation is well described and effective method of sterilization. This paper presents the design,...
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Structural features responsible for control of the eukaryotic GlcN-6-P synthase activity
PublicationGlucosamine-6-phosphate (GlcN-6-P) synthase is responsible for catalysis of the first and practically irreversible step in hexosamine metabolism. As UDP-GlcNAc, the final product of the hexosamine path, constitutes one of the essential substrates for assembly of bacterial and fungal cell walls, the enzyme is an interesting target for antimicrobial therapy.The structure of E. coli enzyme, known since 2001, forms a dimer of two identical...
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Badanie właściwości fotokatalitycznych, biobójczych i magnetycznych tlenku tytanu(IV) modyfikowanego nanocząstkami monoi bimetalicznymi Pt, Ag, Cu, Au oraz Pd
PublicationZakres badań obejmował otrzymywanie i charakterystykę nanokompozytów tlenku tytanu(IV) modyfikowanego mono- oraz bimetalicznymi nanocząstkami metali platyny, palladu, złota, srebra oraz miedzi. Zbadano wpływ zawartości metali, matrycy TiO2 oraz połączeniami metali na właściwości fotokatalityczne, biobójcze i magnetyczne otrzymanych nanokompozytów TiO2. Aktywność fotokatalityczną zbadano w reakcji degradacji modelowych związków oraz...
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Desensitization of glucosamine-6-phosphate synthase to inhibition by UDP-GlcNAc
PublicationGlucosamine-6-phosphate (GlcN-6-P) synthase, known also as L-Glutamine: D-fructose-6-phosphate amidotransferase, catalyzes the first committed step in the pathway leading to the ultimate formation of UDP-GlcNAc. The final product of this pathway is an activated precursor of numerous macromolecules containing amino sugars, including chitin and mannproteins in fungi, peptidoglycan and lipopolysaccharides in bacteria, and glycoproteins...
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Xanthone synthetic derivatives with high anticandidal activity and positive mycostatic selectivity index values
PublicationWith the current massive increases in drug-resistant microbial infection as well as the significant role of fungal infections in the death toll of COVID-19, discovering new antifungals is extremely important. Natural and synthetic xanthones are promising derivatives, although only few reports have demonstrated their antifungal mechanism of action in detail. Newly synthetized by us xanthone derivative 44 exhibited strong antifungal...
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The mechanism of overcoming multidrug resistance (MDR) of fungi by amphotericin B and its derivatives
PublicationPrzeprowadzono badania porównawcze w celu określenia aktywności i cytotoksyczności amfoterycyny B (AmB) i jej pochodnych wobec standardowego szczepu S. cerevisiae i jego transformantów zawierających geny C. albicans kodujące białka oporności wielolekowej (MDR) typu ABC i MFS. Pochodne AmB: amid 3-dimetyloaminopropylowy amfoterycyny B oraz ester metylowy N-metylo-N-D-fruktopiranozylo-amfoterycyny B wykazały efekt fungistatyczny...
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Amphotericin B derivatives: novel strategy for the development of non-toxic, broad spectrum, fungicidal and overcoming multidrug resistance antifungal agents.
PublicationZaprezentowano porównawczą charakterystykę działania amfoterycyny B (AmB) oraz jej pochodnych o różnym stopniu selektywnej toksyczności na szczepy grzybów reperezentujących różne mechanizmy oporności. Były to mutanty C. albicans posiadające defekt w szlaku biosyntezy ergosterolu oraz wielolekooporne szczepy S. cerevisiae wyposażone w pompy eksportujące typu ABC i MFS. Badania obejmowały: 1)porównanie aktywności przeciwgrzybowej...
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Antifungal Effect of Penicillamine Due to the Selective Targeting of L-Homoserine O-Acetyltransferase
PublicationDue to the apparent similarity of fungal and mammalian metabolic pathways, the number of established antifungal targets is low, and the identification of novel ones is highly desirable. The results of our studies, presented in this work, indicate that the fungal biosynthetic pathway of L-methionine, an amino acid essential for humans, seems to be an attractive perspective. The MET2 gene from Candida albicans encoding L-homoserine...
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Antibiotic-Based Conjugates Containing Antimicrobial HLopt2 Peptide: Design, Synthesis, Antimicrobial and Cytotoxic Activities
PublicationRecent studies have shown that modified human lactoferrin 20−31 fragment, named HLopt2, possesses antibacterial and antifungal activity. Thus, we decided to synthesize and evaluate the biological activity of a series of conjugates based on this peptide and one of the antimicrobials with proven antibacterial (ciprofloxacin, CIP, and levofloxacin, LVX) or antifungal (fluconazole, FLC) activity. The drugs were covalently connected...