Project description:The antifungal activity of aurones SH1009 and SH9051 against Candida albicans was investigated. A whole-genome transcriptional analysis post aurone SH1009 and SH9051 treatments on the C. albicans SC5314 strain was performed using RNA-seq technique.
Project description:Natural product cinnamaldehyde has significant antifungal activities, and its inhibitory activity against Candida albicans has been reported. Up to now, there are few reports on the changes in the transcriptome of Candida albicans after cinnamaldehyde treatment. Here, RNA sequencing analysis of samples obtained from Candida albicans cells grown in the presence or absence of cinnamaldehyde was performed. A total of 123 differentially expressed genes were identified, of which 15 genes were up-regulated and 108 genes were down-regulated.
Project description:Candida albicans is a prevalent fungal pathogen in humans worldwide, causing life-threatening invasive candidiasis in immunocompromised individuals, largely due to the scarcity and poor efficacy of present antifungals, necessitating the search for novel antifungal medications.By leveraging machine learning methodologies, we have identified a novel compound that demonstrates robust antifungal activity against C. albicans. To explore the mechanisms behind its efficacy, we undertook an extensive study involving transcriptomic profiling of C. albicansexposed to the compound across different cultivation times and doses.The findings of this study not only contribute to our understanding of antifungal mechanisms, but also have great potential to guide the development of innovative therapies against C. albicans for meeting the growing clinical demand for new treatments.
Project description:Candida albicans is the most prevalent human pathogenic fungus, responsible for drug-resistant and fatal invasive infections which show an increasing trend in the past two decades. A promising new therapeutic approach involves NFAP2, an antifungal protein secreted by Neosartorya (Aspergillus) fischeri. NFAP2 exhibits potent antifungal activity on both planktonic and biofilm-forming Candida cells in vitro and in vivo. Despite this promising feature,the exact antifungal mechanism of NFAP2 remains in the shadow which hampers its therapeutic application. Based on our recent observations, we suppose that NFAP2 is taken up by Candida cells, and has a long-term growth-slowing effect. Our objective was to understand the molecular mechanism of the long-term growth slowing effect of NFAP2 in C. albicans, therefore the transcriptome of the NFAP2-treated (below the minimum inhibitory concentration) C. albicans SC5314 cultures was compared to that of the untreated ones.The transcriptional responses to NFAP2 were further characterized using functional enrichment analyses of Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways.
Project description:Human serum amyloid A (SAA) is a major acute phase protein and shows a massive increase of concentration in plasma during inflammation. In the current study, we report that recombinant human and mouse SAA1 (rhSAA1 and rmSAA1) have a potent antifungal activity against the major fungal pathogen Candida albicans. rhSAA1 binds to the cell surface of C. albicans and promotes cell aggregation. At high concentrations, rhSAA1 disrupts the membrane integrity and induces rapid cell death of C. albicans. Further investigation demonstrates that rhSAA1 targets on the cell wall adhesin Als3 of C. albicans. Inactivation of ALS3 in C. albicans leads to remarkably decreased cell aggregation and death upon rhSAA1 treatment, implying that Als3 plays a critical role in SAA1 sensing. Moreover, deletion of the ALS3 transcriptional regulators such as AHR1, BCR1, and EFG1 in C. albicans results in a similar effect on cell responses to that of the als3/als3 mutant upon rhSAA1 treatment. Global gene expression profiling analysis indicates that rhSAA1 has a remarkable impact on the expression of cell wall- and metabolism-related genes in C. albicans. Our finding of the antifungal activity of rhSAA1 against C. albicans expands the function of this protein and would provide new insights into the understanding of the host-Candida interaction during infections.
Project description:Combination therapies can be a promising tool to augment the antifungal activity of azole drugs against resistant Candida species. Here, we report the interaction between aprepitant, an antiemetic agent, and azole drugs against different Candida species including the emerging multidrug-resistant C. auris. Particularly, aprepitant enhanced the antifungal activity of itraconazole against C. auris by reducing its minimum inhibitory concentration (MIC) by 2-8 folds. Using Caenorhabditis elegans as an in vivo infection model, the aprepitant/itraconazole combination significantly prolonged the survival of the infected nematodes by ~90% and reduced the fungal burden by ~92% relative to the untreated control. Interestingly, the aprepitant/itraconazole combination exerted a potent fungicidal activity against both planktonic and adherent C. auris biofilms. Further, aprepitant/itraconazole displayed broad-spectrum synergistic interactions against other medically important Candida species including C. albicans, C. krusie, C. tropicalis, and C. parapsilosis (ƩFICI ranged from 0.08 to 031). Comparative transcriptomic profiling indicated aprepitant/itraconazole interferes significantly with metal ions homeostasis and compromises the ROS (reactive oxygen species) detoxification ability of C. auris. This study presents aprepitant as a novel, potent and broad-spectrum azole chemosensitizing agent that warrants further investigation.
Project description:Soybean toxin (SBTX) is an antifungal protein from soybeans with broad growth and filamentation inhibitory activity against many fungi, including human and plant pathogenic species such as Candida albicans, Candida parapsilosis, Aspergillus niger, Penicillium herquei, Cercospora sojina, and Cerospora kikuchii. Understanding the mechanism by which SBTX acts on fungi and yeasts may contribute towards the design of novel antifungal drugs and/or for the development of transgenic plants resistant to pathogens. To gain new insights into the mode of action of SBTX, the polymorphic yeast C. albicans was chosen as a model organism, and changes in the gene expression profile of strain SC5314 upon exposure to SBTX were examined. Genes that were differentially regulated in the presence of SBTX were involved in glucose transport and starvation-associated stress responses, as well as in the control of both the induction and repression of C. albicans hyphal formation. Transmission electron microscopy showd that C. albicans cells exposed to SBTX displayed severe signs of starvation and were heavily granulated. Our data were indicative of C. albicans cells starving despite sufficient nutrient availability in the medium, and it can therefore be speculated that SBTX blocks nutrient uptake systems. Because neither the starvation signal nor the alkaline response pathway lead to the induction of hyphae, we hypothesise that conflicting signals are transmitted to the complex regulatory network controlling morphogenesis, eventually preventing the filamentation signal from reaching a significant threshold.
Project description:Sampangine, a plant-derived alkaloid found in the Annonaceae family, exhibits strong inhibitory activity against the opportunistic fungal pathogens Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus. In the present study, transcriptional profiling experiments coupled with the analysis of mutants were performed in an effort to elucidate its mechanism of action. Using Saccharomyces cerevisiae as a model organism, we show that sampangine produces a transcriptional response indicative of hypoxia, altering the expression of genes known to respond to low oxygen conditions. Several additional lines of evidence obtained suggest that these responses could involve effects on heme. First, the hem1 deletion mutant lacking the first enzyme in the heme biosynthetic pathway showed increased sensitivity to sampangine, and exogenously supplied hemin partially rescued the inhibitory activity of sampangine in wild-type cells. In addition, heterozygous mutants with deletions in genes involved in five out of eight steps in the heme biosynthetic pathway showed increased susceptibility to sampangine. Furthermore, spectral analysis of pyridine extracts indicated significant accumulation of free porphyrins in sampangine-treated cells. Transcriptional profiling experiments were also performed in C. albicans to investigate the response of a pathogenic fungal species to sampangine. Taking into account the known differences in the physiological responses of C. albicans and S. cerevisiae to low oxygen, significant correlations were observed between the two transcription profiles suggestive of heme-related defects. Our results indicate that the antifungal activity of the plant alkaloid sampangine is due, at least in part, to perturbations in the biosynthesis or metabolism of heme. GSE10073: Gene expression response to the antifungal compound sampangine in S. cerevisiae GSE10075: Gene expression response to the antifungal compound sampangine in C. albicans Keywords: SuperSeries Refer to individual Series
Project description:Plakortide F acid (PFA), a marine-derived polyketide endoperoxide, exhibits strong inhibitory activity against the opportunistic fungal pathogens Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus. In the present study, transcriptional profiling coupled with mutant and biochemical analyses were conducted using the model organism Saccharomyces cerevisiae, to investigate the mechanism of action of this compound. PFA elicited a transcriptome response indicative of a Ca2+ imbalance, affecting the expression of genes known to be responsive to altered cellular calcium levels. Several additional lines of evidence obtained supported a role for Ca2+ in PFA's activity. First, mutants lacking calcineurin and various Ca2+ transporters including pumps (Pmr1 and Pmc1) and channels (Cch1 and Mid1) showed increased sensitivity to PFA. In addition, the calcineurin inhibitors FK506 and cyclosporine A strongly enhanced PFA activity in wild-type cells. Furthermore, PFA activated the transcription of a lacZ reporter driven by the calcineurin-dependent response element. Finally, elemental analysis indicated a significant increase in intracellular calcium levels in PFA-treated cells. Collectively, our results demonstrate that PFA mediates its antifungal activity by perturbing Ca2+ homeostasis, thus representing a potentially novel mechanism distinct from that of currently used antifungal agents. DNA microarray analysis of gene expression response to the antifungal compound plakortide F acid in yeast