Dataset Information

Transcriptional response of C. albicans to weak organic acids, carbon source and MIG1 inactivation.

ABSTRACT: Candida albicans is a resident fungus of the human intestinal microflora. Commonly isolated at low abundance in healthy people, C. albicans outcompetes local microbiota during candidiasis episodes. Under normal conditions, members of the human gastrointestinal microbiota were shown to keep C. albicans colonization under control. By releasing weak organic acids (WOAs), bacteria are able to moderate yeast growth. This mechanism displayed a synergistic effect in vitro with the absence of glucose in medium of culture, which underline the complex interaction that C. albicans faces in its natural environment. Inactivation of the transcriptional regulator MIG1 in C. albicans results in a lack of sensitivity to this synergistic outcome. To decipher C. albicans transcriptional responses to glucose, WOAs and the role of MIG1, we performed RNA sequencing on four biological replicates exposed to combinations of these 3 parameters. We were able to characterise the i) glucose response, ii) response to acetic and butyric acid, iii) MIG1 regulation of C. albicans and iv) genes responsible for WOAs resistance. We identified a group of 6 genes linked to WOAs sensitivity in a glucose-MIG1-dependent manner and inactivated one of these genes, the putative glucose transporter HGT16, in a SC5314 wild-type background. As expected, the mutant displayed a partial complementation to WOAs resistance in absence of glucose. This result points towards a mechanism of WOAs sensitivity in C. albicans involving membrane transporters which could be exploited to control yeast colonisation in human body niches.

ORGANISM(S): Candida albicans

PROVIDER: GSE99767 | GEO | 2017/10/03

SECONDARY ACCESSION(S): PRJNA389570

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Candida albicans is a part of the normal microbiome of human mucosa and is able to thrive in a wide range of host environments. As an opportunistic pathogen, the virulence of C. albicans is tied to its ability to switch between yeast and hyphal morphologies in response to various environmental cues, one of which includes nutrient availability. Thus, metabolic flexibility plays an important role in the virulence of the pathogen. Our previous study has shown that C. albicans Yeast Casein Kinase 2 (CaYck2) regulates the yeast-to-hyphal switch, but its regulatory mechanisms remain unknown. This study further elucidated the role of Yck2 in governing morphology and carbon metabolism by analyzing the transcriptome and metabolome of the C. albicans YCK2 deletion mutant strain (yck2Δ strain) in comparison to the wild type strain. Our study revealed that loss of CaYck2 perturbs carbon metabolism, leading to a transcriptional response that resembles a transcriptional response to glucose starvation with coinciding intracellular accumulation of glucose and depletion of TCA cycle metabolites. This shift in the metabolome is likely mediated by derepression of glucose-repressed genes in the Mig1/2-mediated glucose sensing pathway and by downregulation of glycolytic genes, possibly through the Rgt1-mediated SRR pathway. In addition, genes involved in beta-oxidation, glyoxylate cycle, oxidative stress response, and arginine biosynthesis were upregulated in the yck2Δ strain, which is highly reminiscent of C. albicans engulfment by macrophages. This coincides with an increase in arginine degradation intermediates in the yck2Δ strain, suggesting arginine catabolism as a potential mechanism of CaYck2-mediated filamentation as seen during C. albicans escape from macrophages. Transcriptome analysis also shows differential expression of hyphal transcriptional regulators Nrg1 and Ume6. This suggests dysregulation of hyphal initiation and elongation in the yck2Δ strain which may lead to the constitutive pseudohyphal phenotype of this strain. Metabolome analysis also detected a high abundance of methyl citrate cycle intermediates in the yck2Δ strain, suggesting the importance of CaYck2 in this pathway. Taken together, we discovered that CaYck2 is an integral piece of carbon metabolism and morphogenesis of C. albicans.

Project description:Familial Mediterranean fever (FMF) is an inflammatory genetic disease characterized by elevated systemic reactivity against commensal gut microbiota and high levels of gut Candida albicans. The current study investigated the effects of Lactobacillus acidophillus INMIA 9602 Er 317/402 strain (probiotic “Narine”) on the relative abundance of gut enteric bacteria, lactobacilli, Staphylococcus aureus, and Enteroccocus faecalis in Candida albicans-carrier and non-carrier FMF patients in remission with the main MEFV mutation patterns M694V/V726A- the prevalent MEFV gene mutation within FMF patients in the Armenian cohort. Our data revealed that M694V/V726A mutations in PURIN inflammasome leading to FMF disease brought to gender specific differences in microbial community structure in FMF patients. Possibly, long-term colchicine use suppresses the PURIN inflammasome/inhibits NLRP3 inflammasome-dependent IL-1β release influencing on overgrowth of C. albicans in gut microbiota of FMF patients. The comparison of Operational Taxonomic Units (OTUs) of enteric bacteria in C. albicans-carrier and non-carrier female patients revealed the statistically significant increase in OTUs of enterobacteria in C. albicans-carriers. In contrast to this, there were no differences in abundance of Enteroccocus faecalis between female FMF C. albicans-carriers compared with non-carriers, while male FMF C. albicans-carriers have increased abundance of E. faecalis in their gut microbiota compared with that of male patients with none carriers. The gut microbiota of FMF patients (both male and female) with C. albicans below baseline level contains high abundance of lactobacilli compared with C. albicans-carriers. The adoption of Lactobacillus acidophilus INMIA 9602 Er 317/402 leads to changes in gut microbiota composition of FMF patients. It reduces, in particularly, the abundance of enterobacteria in females, and Enteroccocus faecalis in men parallel with reducing the numbers of yeast in gut microbiota of FMF patients. We hypothesize that colchicine treatment changes the already-altered gut microbiota of FMF patients, thereby affecting the regulation of immune system by inhibition of NLRP3 inflammasome. Colchicine could lead to overgrowth of C. albicans in gut microbiota of FMF patients, whereas the Lactobacillus acidophilus INMIA 9602 Er 317/402 works on activation of inflammasome by new changes in gut microbiota of patients.

Project description:Candida albicans is the most important fungal pathogen of humans, causing severe infections especially in nosocomial and immunocompromised settings. However, it is also the most prevalent fungus of the normal human microbiome, where it shares its habitat with hundreds of trillions of other microbial cells. Despite weak organic acids (WOAs) being among the most abundant metabolites produced by bacterial microbiota, little is known about their effect on C. albicans. Here we employed a sequencing-based profiling strategy to systematically investigate the transcriptional stress response of C. albicans to lactic, acetic, propionic and butyric acid at several time points after treatment. Our data reveal a complex transcriptional response, with individual WOAs triggering unique gene expression profiles and with important differences between acute and chronic exposure. In spite of all these dissimilarities, we found significant overlaps between the gene expression changes induced by each WOA, which lead us to uncover a core transcriptional signature that was unrelated to the general response to low pH. Genes commonly up-regulated by WOAs were enriched in several iron transporters, which was associated with an overall decrease in intracellular iron concentrations. Moreover, chronic exposure to any WOA lead to down-regulation of RNA synthesis and ribosome biogenesis genes, which resulted in significant reduction of total RNA levels in general and of ribosomal RNA in particular. In conclusion, this study suggests that GI microbiota might directly influence C. albicans physiology via production of WOAs, with possible implications of how this fungus interacts with its hosts in both health and disease. Transcriptional profiling of wild-type Candida albicans strain SC5314 under 6 differents condition (2 controls, 4 weak acids) at 4 time points by cDNA deep-sequencing, with 4 biological replicates, on the Illumina HiSeq 2000 platform. 96 total samples were sequenced (6 x 4 x 4).

Dataset Information

Transcriptional response of C. albicans to weak organic acids, carbon source and MIG1 inactivation.

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets