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Full-Text Articles in Fungi
Polymorphic Α-Glucans As Structural Scaffolds In Cryptococcus Cell Walls For Chitin, Capsule, And Melanin: Insights From 13c And 1h Solid-State Nmr, Ankur Ankur, Jayasubba Reddy Yarava, Isha Gautam, Faith J. Scott, Frederic Mentink-Vigier, Christine Chrissian, Li Xie, Dibakar Roy, Ruth E. Stark, Tamara L. Doering, Ping Wang, Tuo Wang
Polymorphic Α-Glucans As Structural Scaffolds In Cryptococcus Cell Walls For Chitin, Capsule, And Melanin: Insights From 13c And 1h Solid-State Nmr, Ankur Ankur, Jayasubba Reddy Yarava, Isha Gautam, Faith J. Scott, Frederic Mentink-Vigier, Christine Chrissian, Li Xie, Dibakar Roy, Ruth E. Stark, Tamara L. Doering, Ping Wang, Tuo Wang
School of Graduate Studies Faculty Publications
Cryptococcus species are major fungal pathogens responsible for life-threatening infections in approximately a million individuals globally each year, with alarmingly high mortality rates. These fungi are distinguished by a distinctive cell wall architecture further reinforced by two virulence-associated layers, melanin and capsule, rendering them insensitive to antifungal agents targeting the cell wall, such as echinocandins. The molecular interplay between these three biomolecular layers remains poorly understood. Here we employ solid-state NMR spectroscopy to examine intact cells of both wild-type and capsule-deficient strains of C. neoformans, along with melanized cells. High-resolution 13C and 1H data revealed five distinct structural forms of …
Discovering Novel Polyextremotolerant Fungi And Determining Their Ecological Role Within The Biological Soil Crust Consortium, Erin C. Carr
Discovering Novel Polyextremotolerant Fungi And Determining Their Ecological Role Within The Biological Soil Crust Consortium, Erin C. Carr
School of Biological Sciences: Dissertations, Theses, and Student Research
The ecological niche of polyextremotolerant fungi within oligotrophic ecosystems such as biological soil crusts has not yet been determined. These fungi persist in locations where nutrients are depleted while simultaneously surrounded by autotrophic microbes such as algae and cyanobacteria. Yet it has not been shown that they are engaging in any exchange of nutrients the way lichens do. However, there is seemingly no other way for these fungi to obtain vital nutrients, such as carbon or nitrogen, other than from these microbes. Here we have isolated polyextremotolerant fungi from cold desert biological soil crusts which are a microbial biofilm that …
Cryptococcus Neoformans Melanization Incorporates Multiple Catecholamines To Produce Polytypic Melanin, Rosanna P. Baker, Christine Chrissian, Ruth E. Stark, Arturo Casadevall
Cryptococcus Neoformans Melanization Incorporates Multiple Catecholamines To Produce Polytypic Melanin, Rosanna P. Baker, Christine Chrissian, Ruth E. Stark, Arturo Casadevall
Publications and Research
Melanin is a major virulence factor in pathogenic fungi that enhances the ability of fungal cells to resist immune clearance. Cryptococcus neoformans is an important human pathogenic fungus that synthesizes melanin from exogenous tissue catecholamine precursors during infection, but the type of melanin made in cryptococcal meningoencephalitis is unknown. We analyzed the efficacy of various catecholamines found in brain tissue in supporting melanization using animal brain tissue and synthetic catecholamine mixtures reflecting brain tissue proportions. Solid-state NMR spectra of the melanin pigment produced from such mixtures yielded more melanin than expected if only the preferred constituent dopamine had been incorporated, …
Fungal Melanin: What Do We Know About Structure?, Joshua D. Nosanchuk, Ruth E. Stark, Arturo Casadevall
Fungal Melanin: What Do We Know About Structure?, Joshua D. Nosanchuk, Ruth E. Stark, Arturo Casadevall
Publications and Research
The production of melanin significantly enhances the virulence of many important human pathogenic fungi. Despite fungal melanin’s importance in human disease, as well as melanin’s contribution to the ability of fungi to survive in diverse hostile environments, the structure of melanin remains unsolved. Nevertheless, ongoing research efforts have progressively revealed several notable structural characteristics of this enigmatic pigment, which will be the focus of this review. These compositional and organizational insights could further our ability to develop novel therapeutic approaches to combat fungal disease and enhance our understanding of how melanin is inserted into the cell wall.