Achilonu, Conrad C

Introduction. Aspergillus fumigatus phosphoglucomutase ( Af PGM) is a central enzyme in fungal carbohydrate metabolism that catalyses the interconversion of glucose-1-phosphate and glucose-6-phosphate, generating precursors such as uridine diphosphate glucose required for the synthesis of key cell wall polysaccharides. Hypothesis/Gap Statement. Although Af PGM has been implicated in fungal viability and cell wall integrity, further functional and molecular characterization is required to better define its role in cell wall-associated processes and to evaluate its potential as a selective antifungal target. Aim. This study aimed to further characterize the functional contribution of Af PGM to fungal growth, cell wall-related phenotypes, biofilm formation and enzymatic activity. Methodology. A conditional A. fumigatus P alcA ::pgm mutant was used to assess growth, soluble β -glucan levels and biofilm formation. Functional complementation was evaluated by heterologous expression of Afpgm in a Saccharomyces cerevisiae pgm2Δ strain. Enzymatic inhibition was examined using the isothiazolone compound ISFP10. Results. Reduced Af PGM activity was associated with impaired growth, altered cell wall-related phenotypes, decreased soluble β -glucan levels and diminished biofilm biomass. Expression of Afpgm restored growth and sedimentation defects in the yeast pgm2Δ mutant to WT levels, confirming functional conservation. ISFP10 inhibited Af PGM activity and disrupted associated fungal phenotypes. Conclusion. These findings further define the functional role of Af PGM in fungal carbohydrate metabolism and cell wall-associated biology. The selective inhibition of Af PGM relative to human phosphoglucomutase supports its potential as a promising target for the development of novel antifungal therapies.

Abstract Candida auris is an emerging fungal pathogen with high rates of multidrug resistance, posing a significant global health threat. Immunosuppressed patients are particularly vulnerable to multidrug-resistant (MDR) C. auris infections. This systematic review and meta-analysis (SR-MA) aimed to assess the global prevalence of MDR-C. auris isolates in humans and their resistance to antifungal drugs, primarily fluconazole (FLZ), voriconazole (VOR), and amphotericin B (AmB). A comprehensive search was conducted in PubMed, Scopus, and ScienceDirect databases on published studies regarding clinical C. auris isolates and the use of antifungal susceptibility testing assay from 17 March 2015 to 1 February 2024. Meta-analysis was conducted using random-effects models to determine the estimated pooled prevalence of MDR-C. auris isolates and their antifungal resistance profiles from immunosuppressed humans. A total of 81 research studies were included in the final analysis, with the overall pooled prevalence of the three most important antifungal drugs; FLZ (92.5% | 95% CI: 89.5–94.7), VOR (49.0% | 95% CI: 37.6–60.4), and AmB (51.0% | 95% CI: 42.3–59.7). According to the subgroup analyses, FLZ-resistant C. auris was the most prevalent isolate observed in the five continents reporting compared to the VOR- and AmB-resistant C. auris having lower pooled prevalence. Further, higher pooled prevalence of MDR-C. auris isolates were observed from males (68.2%, n = 578) compared to females (37.1%, n = 283). Finally, the global pooled prevalence for mortality in immunosuppressed patients with MDR-C. auris from 13 research studies was 41.5% (95% CI: 29.9–54.2). This SR-MA study establishes the variation of MDR-C. auris resistance patterns observed from different continents and the importance to conduct further research studies using potent antifungal drugs. Accordingly, it is imperative to establish stringent surveillance on the increasing prevalence of antifungal resistance particularly in low-income regions with limited research resources to prevent increasing prevalence of MDR-C. auris.