A multifunctional, synthetic Gaussia princeps luciferase reporter for live imaging of Candida albicans infections

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Mechanisms Underlying the Delayed Activation of the Cap1 Transcription Factor in Candida albicans following Combinatorial Oxidative and Cationic Stress Important for Phagocytic Potency

ACKNOWLEDGMENTS We are grateful to Brian Morgan and Elizabeth Veal for insightful discussions, Mélanie Ikeh for experimental assistance, and Scott Moye-Rowley (University of Iowa) for the gift of the anti-Cap1 antibody. This work was funded by the NIHR Newcastle Biomedical Research Centre (I.K.), a BBSRC DTG studentship (M.J.P.), the Wellcome Trust (grants 089930 and 097377 to J.Q. and 080088 and 097377 to A.J.P.B.), the BBSRC (grants BB/K016393/1 to J.Q. and BB/F00513X/1 and BB/K017365/1 to A.J.P.B.), the European Research Council (STRIFE Advanced grant ERC-2009-AdG-249793 to A.J.P.B.), the ANR (grant CANDIHUB, ANR-14-CE14-0018-01, to C.D.), and the French Government’s Investissement d’Avenir program (grant IBEID, ANR-10-LABX-62-IBEID, to C.D.). FUNDING INFORMATION This work, including the efforts of Alistair J.P. Brown, was funded by Wellcome Trust (097377 and 080088). This work, including the efforts of Janet Quinn, was funded by Wellcome Trust (097377 and 089930). This work, including the efforts of Alistair J.P. Brown, was funded by EC European Research Council (ERC) (ERC-2009-AdG-249793). This work, including the efforts of Alistair J.P. Brown, was funded by Biotechnology and Biological Sciences Research Council (BBSRC) (BB/F00513X/1 and BB/K017365/1). This work, including the efforts of Janet Quinn, was funded by Biotechnology and Biological Sciences Research Council (BBSRC) (BB/K016393/1). This work, including the efforts of Christophe d’Enfert, was funded by Agence Nationale de la Recherche (ANR) (ANR-14-CE14-0018-01 and ANR-10-LABX-62-IBEID).Peer reviewedPublisher PD

Shotgun metagenomics reveals interkingdom association between intestinal bacteria and fungi involving competition for nutrients

Comprehensive database; Diet; MicrobiomeBase de datos integral; Dieta; MicrobiomaBase de dades integral; Dieta; MicrobiomaBackground The accuracy of internal-transcribed-spacer (ITS) and shotgun metagenomics has not been robustly evaluated, and the effect of diet on the composition and function of the bacterial and fungal gut microbiome in a longitudinal setting has been poorly investigated. Here we compared two approaches to study the fungal community (ITS and shotgun metagenomics), proposed an enrichment protocol to perform a reliable mycobiome analysis using a comprehensive in-house fungal database, and correlated dietary data with both bacterial and fungal communities. Results We found that shotgun DNA sequencing after a new enrichment protocol combined with the most comprehensive and novel fungal databases provided a cost-effective approach to perform gut mycobiome profiling at the species level and to integrate bacterial and fungal community analyses in fecal samples. The mycobiome was significantly more variable than the bacterial community at the compositional and functional levels. Notably, we showed that microbial diversity, composition, and functions were associated with habitual diet composition instead of driven by global dietary changes. Our study indicates a potential competitive inter-kingdom interaction between bacteria and fungi for food foraging. Conclusion Together, our present work proposes an efficient workflow to study the human gut microbiome integrating robustly fungal, bacterial, and dietary data. These findings will further advance our knowledge of the interaction between gut bacteria and fungi and pave the way for future investigations in human mycobiome.This work was supported by the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Action, Innovative Training Network [grant number 812969]

A High-Throughput Candida albicans Two-Hybrid System

We thank Nico Vangoethem for help with preparation of the figures and Ilse Palmans, Tom Adriany, and Selien Schots for technical assistance. Financial support was obtained from the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (IAP P7/28) and by the KU Leuven Research Council (C14/17/063). C.D. acknowledges support from the French Government’s Investissement d’Avenir program (Laboratoire d’Excellence Integrative Biology of Emerging Infectious Diseases, ANR-10-LABX-62-IBEID). C.A.M. and C.D. acknowledge support from the Wellcome Trust (088858/Z/09/Z). C.A.M. acknowledges support from the MRC Centre for Medical Mycology (MR/N006364/1) and the University of Aberdeen.Peer reviewedPublisher PD

The pathogenic and colonization potential of Candida africana

The Candida albicans population displays high genetic diversity illustrated by 18-well differentiated genetic clusters. Cluster 13, also known as Candida africana, is an outlying cluster and includes strains first described as atypical C. albicans isolates of vaginal origin, showing apparent tropism for the female genital tract. In our study, we combined in vitro, and in vivo models to explore the colonization and pathogenic potential of C. africana. We report that C. africana has similar fitness to C. albicans when it comes to colonization of the oral and vaginal mucosa, however it has decreased fitness in gastro-intestinal colonization and systemic infection. Interestingly, despite high population homogeneity, our in vitro data highlighted for the first time a variability in terms of growth rate, biofilm formation and filamentation properties between C. africana strains. Overall, our data lays the foundations for exploring specific features of C. africana that might contribute to its apparent niche restriction

Synergy of the antibiotic colistin with echinocandin antifungals in Candida species.

International audienceOBJECTIVES: Candida albicans is the most prevalent fungal pathogen of humans, causing a wide range of infections from harmless superficial to severe systemic infections. Improvement of the antifungal arsenal is needed since existing antifungals can be associated with limited efficacy, toxicity and antifungal resistance. Here we aimed to identify compounds that act synergistically with echinocandin antifungals and that could contribute to a faster reduction of the fungal burden. METHODS: A total of 38 758 compounds were tested for their ability to act synergistically with aminocandin, a β-1,3-glucan synthase inhibitor of the echinocandin family of antifungals. The synergy between echinocandins and an identified hit was studied with chemogenomic screens and testing of individual Saccharomyces cerevisiae and C. albicans mutant strains. RESULTS: We found that colistin, an antibiotic that targets membranes in Gram-negative bacteria, is synergistic with drugs of the echinocandin family against all Candida species tested. The combination of colistin and aminocandin led to faster and increased permeabilization of C. albicans cells than either colistin or aminocandin alone. Echinocandin susceptibility was a prerequisite to be able to observe the synergy. A large-scale screen for genes involved in natural resistance of yeast cells to low doses of the drugs, alone or in combination, identified efficient sphingolipid and chitin biosynthesis as necessary to protect S. cerevisiae and C. albicans cells against the antifungal combination. CONCLUSIONS: These results suggest that echinocandin-mediated weakening of the cell wall facilitates colistin targeting of fungal membranes, which in turn reinforces the antifungal activity of echinocandins

Identification of an active RNAi pathway in Candida albicans

RNA interference (RNAi) is a fundamental regulatory pathway with a wide range of functions, including regulation of gene expression and maintenance of genome stability. Although RNAi is widespread in the fungal kingdom, well-known species, such as the model yeast , have lost the RNAi pathway. Until now evidence has been lacking for a fully functional RNAi pathway in , a human fungal pathogen considered critically important by the World Health Organization. Here, we demonstrated that the widely used reference strain (SC5314) contains an inactivating missense mutation in the gene encoding for the central RNAi component Argonaute. In contrast, most other isolates contain a canonical Argonaute protein predicted to be functional and RNAi-active. Indeed, using high-throughput small and long RNA sequencing combined with seamless CRISPR/Cas9-based gene editing, we demonstrate that an active RNAi machinery represses expression of subtelomeric gene families. Thus, an intact and functional RNAi pathway exists in , highlighting the importance of using multiple reference strains when studying this dangerous pathogen

The NDR/LATS Kinase Cbk1 Controls the Activity of the Transcriptional Regulator Bcr1 during Biofilm Formation in Candida albicans

In nature, many microorganisms form specialized complex, multicellular, surface-attached communities called biofilms. These communities play critical roles in microbial pathogenesis. The fungal pathogen Candida albicans is associated with catheter-based infections due to its ability to establish biofilms. The transcription factor Bcr1 is a master regulator of C. albicans biofilm development, although the full extent of its regulation remains unknown. Here, we report that Bcr1 is a phosphoprotein that physically interacts with the NDR kinase Cbk1 and undergoes Cbk1-dependent phosphorylation. Mutating the two putative Cbk1 phosphoacceptor residues in Bcr1 to alanine markedly impaired Bcr1 function during biofilm formation and virulence in a mouse model of disseminated candidiasis. Cells lacking Cbk1, or any of its upstream activators, also had reduced biofilm development. Notably, mutating the two putative Cbk1 phosphoacceptor residues in Bcr1 to glutamate in cbk1Δ cells upregulated the transcription of Bcr1-dependent genes and partially rescued the biofilm defects of a cbk1Δ strain. Therefore, our data uncovered a novel role of the NDR/LATS kinase Cbk1 in the regulation of biofilm development through the control of Bcr1

Systematic Gene Overexpression in Candida albicans identifies a Regulator of Early Adaptation to the Mammalian Gut

We are grateful to members of the genomics core facility (PF2, Génopole) for the availability of the microarray scanner and the Alain Jacquier’s lab for making the GenePix software available. We are grateful to Drs. Suzanne Noble and Aaron Mitchell for providing C. albicans mutant collections. We thank all members of the Fungal Biology & Pathogenicity Unit, particularly Drs. Anne Neville and Adeline Feri for their numerous insights during the course of this project. This work has been supported by grants from the Agence Nationale de la Recherche (KANJI, ANR-08-MIE-033-01 to C.d’E. and F.D.; ERA-Net Infect-ERA, FUNCOMPATH, ANR-14-IFEC-0004; and CANDIHUB, ANR-14-CE-0018 to C.d’E.), the French Government’s Investissement d’Avenir program (Laboratoire d’Excellence Integrative Biology of Emerging Infectious Diseases, ANR-10-LABX-62-IBEID to C.d’E.; Institut de Recherche Technologique BIOASTER, ANR-10-AIRT-03 to C.d’E., F.D. and T.J.), the European Commission (FinSysB PITN-GA-2008-214004 to C.d’E.) and the Wellcome Trust (The Candida albicans ORFeome project, WT088858MA to C.d’E. and C.M.). C.M. acknowledges support from the Medical Research Council, UK (New Investigator Award, G0400284), the MRC Centre for Medical Mycology (MR/N006364/1) and the University of Aberdeen. S.Z. is an Institut Pasteur International Network Affiliate Program Fellow. S.Z., L.v.W. and A.H.C. were the recipients of post-doctoral fellowships from the European Commission (FINSysB, PITN-GA-2008-214004 to S.Z.), the Agence Nationale de la Recherche (KANJI, ANR-08-MIE-033-01 to S.Z.; ERA-Net Infect-ERA, FUNCOMPATH, ANR-14-IFEC-0004 to A.H.C.; CANDIHUB, ANR-14-CE-0018 to L.v.W) and the French Government’s Investissement d’Avenir program (Institut de Recherche Technologique BIOASTER, ANR-10-AIRT-03 to S.Z. and A.H.C.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

Unveiling Candida albicans intestinal carriage in healthy volunteers : the role of micro- and mycobiota, diet, host genetics and immune response

Acknowledgements This work was supported by a grant from Agence Nationale de la Recherche (FunComPath ANR-14-IFEC-0004), the French Government’s Investissement d’Avenir program (Laboratoire d’Excellence Integrative Biology of Emerging Infectious Diseases [ANR10-LABX-62-IBEID], and [ANR-10-LABX-69-01]), the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie action, Innovative Training Network (FunHoMic; Grant No. 812969 ), and the European Union's Horizon 2020 Research and Innovation Program (HDM-FUN, Grant No. 847507). AWW and the Rowett Institute (University of Aberdeen) received core funding support from the Scottish Government’s Rural and Environmental Sciences and Analytical Services (RESAS).Peer reviewedPublisher PD