Oxidative Stress Responses in the Human Fungal Pathogen, Candida albicans

Dantas, Alessandra da Silva; Day, Alison M.; Ikeh, Mélanie; Kos, Iaroslava; Achan, Beatrice; Quinn, Janet

doi:10.3390/biom5010142

Cited by 217 publications

(164 citation statements)

References 125 publications

Supporting

Mentioning

147

Contrasting

Unclassified

Order By: Relevance

“…Enzymatic degradation of antimicrobial agents by means of catalases or peroxidases is a common strategy in pathogenic bacteria [34,35] and fungi [36,37]. Catalases are able to ‘detoxify’ H 2 O 2 by breakdown into H 2 O and O 2 , which is visualised by a bubbling reaction.…”

Section: Discussionmentioning

confidence: 99%

Efficacy of chemical disinfectants for the containment of the salamander chytrid fungus Batrachochytrium salamandrivorans

et al. 2017

View full text Add to dashboard Cite

The recently emerged chytrid fungus Batrachochytrium salamandrivorans (Bsal) causes European salamander declines. Proper hygiene protocols including disinfection procedures are crucial to prevent disease transmission. Here, the efficacy of chemical disinfectants in killing Bsal was evaluated. At all tested conditions, Biocidal®, Chloramine-T®, Dettol medical®, Disolol®, ethanol, F10®, Hibiscrub®, potassium permanganate, Safe4®, sodium hypochlorite, and Virkon S®, were effective at killing Bsal. Concentrations of 5% sodium chloride or lower, 0.01% peracetic acid and 0.001–1% copper sulphate were inactive against Bsal. None of the conditions tested for hydrogen peroxide affected Bsal viability, while it did kill Batrachochytrium dendrobatidis (Bd). For Bsal, enzymatic breakdown of hydrogen peroxide by catalases and specific morphological features (clustering of sporangia, development of new sporangia within the original sporangium), were identified as fungal factors altering susceptibility to several of the disinfectants tested. Based on the in vitro results we recommend 1% Virkon S®, 4% sodium hypochlorite and 70% ethanol for disinfecting equipment in the field, lab or captive setting, with a minimal contact time of 5 minutes for 1% Virkon S® and 1 minute for the latter disinfectants. These conditions not only efficiently target Bsal, but also Bd and Ranavirus.

show abstract

Section: Discussionmentioning

confidence: 99%

Efficacy of chemical disinfectants for the containment of the salamander chytrid fungus Batrachochytrium salamandrivorans

et al. 2017

View full text Add to dashboard Cite

show abstract

“…These results extend previous observations that the circuits in white and opaque cells are differentially wired for filamentation and that distinct stimuli induce filamentation in the two states (59, 80). In addition, both cell types exhibited filamentous growth in the presence of chemical stressors, likely reflecting a shared morphological response to delayed cell cycle progression (81, 82). …”

Section: Discussionmentioning

confidence: 99%

Phenotypic Profiling Reveals that Candida albicans Opaque Cells Represent a Metabolically Specialized Cell State Compared to Default White Cells

Ene

Lohse

Vladu

et al. 2016

mBio

View full text Add to dashboard Cite

The white-opaque switch is a bistable, epigenetic transition affecting multiple traits in Candida albicans including mating, immunogenicity, and niche specificity. To compare how the two cell states respond to external cues, we examined the fitness, phenotypic switching, and filamentation properties of white cells and opaque cells under 1,440 different conditions at 25°C and 37°C. We demonstrate that white and opaque cells display striking differences in their integration of metabolic and thermal cues, so that the two states exhibit optimal fitness under distinct conditions. White cells were fitter than opaque cells under a wide range of environmental conditions, including growth at various pHs and in the presence of chemical stresses or antifungal drugs. This difference was exacerbated at 37°C, consistent with white cells being the default state of C. albicans in the mammalian host. In contrast, opaque cells showed greater fitness than white cells under select nutritional conditions, including growth on diverse peptides at 25°C. We further demonstrate that filamentation is significantly rewired between the two states, with white and opaque cells undergoing filamentous growth in response to distinct external cues. Genetic analysis was used to identify signaling pathways impacting the white-opaque transition both in vitro and in a murine model of commensal colonization, and three sugar sensing pathways are revealed as regulators of the switch. Together, these findings establish that white and opaque cells are programmed for differential integration of metabolic and thermal cues and that opaque cells represent a more metabolically specialized cell state than the default white state.

show abstract

“…Antioxidant capacity is crucial for C. albicans to neutralize oxidative stress (33,34). We hypothesized that the reduced AHP1 expression found in the haploid biofilm might have caused a significant drop of the antioxidant potential, which contributes to the higher susceptibility to amphotericin B.…”

Section: Identification Of Ahp1 As a Critical Determinant Of C Albicmentioning

confidence: 99%

Comparative Ploidy Proteomics of Candida albicans Biofilms Unraveled the Role of the AHP1 Gene in the Biofilm Persistence Against Amphotericin B

Truong

Zeng

Lin

et al. 2016

Molecular & Cellular Proteomics

View full text Add to dashboard Cite

Candida albicans is a major fungal pathogen causing lethal infections in immunocompromised patients. C. albicans forms antifungal tolerant biofilms contributing significantly to therapeutic failure. The recently established haploid C. albicans biofilm model provides a new toolbox to uncover the mechanism governing the higher antifungal tolerance of biofilms. Here, we comprehensively examined the proteomics and antifungal susceptibility of standard diploid (SC5314 and BWP17) and stable haploid (GZY792 and GZY803) strains of C. albicans biofilms. Subsequent downstream analyses identified alkyl hydroperoxide reductase 1 (AHP1) as a critical determinant of C. albicans biofilm's tolerance of amphotericin B. At 32 g/ml of amphotericin B, GZY803 haploid biofilms showed 0.1% of persister population as compared with 1% of the diploid biofilms. AHP1 expression was found to be lower in GZY803 biofilms, and AHP1 overexpression in GZY803 restored the percentage of persister population. Consistently, deleting AHP1 in the diploid strain BWP17 caused a similar increase in amphotericin B susceptibility. AHP1 expression was also positively correlated with the antioxidant potential. Furthermore, C. albicans ira2⌬/⌬ biofilms were susceptible to amphotericin B and had a diminished antioxidant capacity. Interestingly, AHP1 overexpression in the ira2⌬/⌬ strain restored the antioxidant potential and enhanced the persister population against amphotericin B, and shutting down the AHP1 expression in ira2⌬/⌬ biofilms reversed the effect. In conclusion, we provide evidence that the AHP1 gene critically determines the amphotericin B tolerance of C. albicans biofilms possibly by maintaining the persisters' antioxidant capacity. This finding will open up new avenues for developing therapies targeting the persister population of C. albicans biofilms. The mass spectrometry proteomics data are available via ProteomeXchange with identifier PXD004274. Molecular & Cellular

show abstract

Oxidative Stress Responses in the Human Fungal Pathogen, Candida albicans

Cited by 217 publications

References 125 publications

Efficacy of chemical disinfectants for the containment of the salamander chytrid fungus Batrachochytrium salamandrivorans

Efficacy of chemical disinfectants for the containment of the salamander chytrid fungus Batrachochytrium salamandrivorans

Phenotypic Profiling Reveals that Candida albicans Opaque Cells Represent a Metabolically Specialized Cell State Compared to Default White Cells

Comparative Ploidy Proteomics of Candida albicans Biofilms Unraveled the Role of the AHP1 Gene in the Biofilm Persistence Against Amphotericin B

Contact Info

Product

Resources

About