An Assessment of Infrared Spectra as Indicators of Fungal Cell Wall Composition

Infrared spectroscopy is assessed as a technique for identifying polymers derived from fungal cell walls, both as isolated materials and in mixtures with one another. The technique is then applied to a study of the composition of fungal cell walls and the conclusion reached that infrared spectra provide a rapid and valuable indication of the major components of such walls. They can also be used to follow the effect of chemical treatments designed to separate major wall components.

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Interactions of proteins with other wall components: a pivotal step in fungal cell wall construction

Canadian Journal of Botany ◽

10.1139/b95-273 ◽

1995 ◽

Vol 73 (S1) ◽

pp. 384-387 ◽

Cited By ~ 3

Author(s):

R. Sentandreu ◽

M. Sentandreu ◽

M. V. Elorza ◽

M. Iranzo ◽

S. Mormeneo

Keyword(s):

Cell Wall ◽

Protein Interactions ◽

Cell Walls ◽

Noncovalent Interactions ◽

Fungal Cell Wall ◽

Fungal Cell ◽

Covalent Bonds ◽

Viscoelastic Composite ◽

Wall Construction ◽

Wall Components

Following synthesis of its individual components, the cell wall of Candida albicans is assembled extracellularly in two steps. First, a viscoelastic composite is formed by noncovalent interactions between mannoproteins and other wall components. Second, the initial network is consolidated by formation of covalent cross-linkages among the wall polymers. In both processes, specific proteins may regulate the final yeast or mycelial morphology. These proteins might carry out part of what could be called a morphogenetic code. Experimental results have shown that some mannoproteins form supramolecular complexes. They are secreted independently, but released together from cell walls by hydrolases. In C. albicans cell walls a transglutaminase activity has been detected that could be responsible for the formation of covalent bonds between structural proteins. Key words: fungal cell wall, construction, morphogenesis, protein interactions, noncovalent linkages, covalent linkages.

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Mannan detecting C-type lectin receptor probes recognise immune epitopes with diverse chemical, spatial and phylogenetic heterogeneity in fungal cell walls

10.1101/677104 ◽

2019 ◽

Author(s):

Ingrida Vendele ◽

Janet A. Willment ◽

Lisete M. Silva ◽

Angelina S. Palma ◽

Wengang Chai ◽

...

Keyword(s):

Cell Wall ◽

Immune Responses ◽

Cell Walls ◽

Fungal Pathogens ◽

Fungal Species ◽

Fungal Cell Wall ◽

Immune Recognition ◽

Cell Surfaces ◽

Fungal Cell ◽

Wall Components

AbstractDuring the course of fungal infection, pathogen recognition by the innate immune system is critical to initiate efficient protective immune responses. The primary event that triggers immune responses is the binding of Pattern Recognition Receptors (PRRs), which are expressed at the surface of host immune cells, to Pathogen-Associated Molecular Patterns (PAMPs) located predominantly in the fungal cell wall. Most fungi have mannosylated PAMPs in their cell walls and these are recognized by a range of C-type lectin receptors (CTLs). However, the precise spatial distribution of the ligands that induce immune responses within the cell walls of fungi are not well defined. We used recombinant IgG Fc-CTLs fusions of three murine mannan detecting CTLs, including dectin-2, the mannose receptor (MR) carbohydrate recognition domains (CRDs) 4-7 (CRD4-7), and human DC-SIGN (hDC-SIGN) and the β-1,3 glucan-binding lectin dectin-1 to map PRR ligands in the fungal cell wall. We show that epitopes of mannan-specific CTL receptors can be clustered or diffuse, superficial or buried in the inner cell wall. We demonstrate that PRR ligands do not correlate well with phylogenetic relationships between fungi, and that Fc-lectin binding discriminated between mannosides expressed on different cell morphologies of the same fungus. We also demonstrate CTL epitope differentiation during different phases of the growth cycle ofCandida albicansand that MR and DC-SIGN labelled outer chainN-mannans whilst dectin-2 labelled coreN-mannans displayed deeper in the cell wall. These immune receptor maps of fungal walls therefore reveal remarkable spatial, temporal and chemical diversity, indicating that the triggering of immune recognition events originates from multiple physical origins at the fungal cell surface.Author SummaryInvasive fungal infections remain an important health problem in immunocompromised patients. Immune recognition of fungal pathogens involves binding of specific cell wall components by pathogen recognition receptors (PRRs) and subsequent activation of immune defences. Some cell wall components are conserved among fungal species while other components are species-specific and phenotypically diverse. The fungal cell wall is dynamic and capable of changing its composition and organization when adapting to different growth niches and environmental stresses. Differences in the composition of the cell wall lead to differential immune recognition by the host. Understanding how changes in the cell wall composition affect recognition by PRRs is likely to be of major diagnostic and clinical relevance. Here we address this fundamental question using four soluble immune receptor-probes which recognize mannans and β-glucan in the cell wall. We use this novel methodology to demonstrate that mannan epitopes are differentially distributed in the inner and outer layers of fungal cell wall in a clustered or diffuse manner. Immune reactivity of fungal cell surfaces did not correlate with relatedness of different fungal species, and mannan-detecting receptor-probes discriminated between cell surface mannans generated by the same fungus growing under different conditions. These studies demonstrate that mannan-epitopes on fungal cell surfaces are differentially distributed within and between the cell walls of fungal pathogens.

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Evolutionary Overview of Molecular Interactions and Enzymatic Activities in the Yeast Cell Walls

International Journal of Molecular Sciences ◽

10.3390/ijms21238996 ◽

2020 ◽

Vol 21 (23) ◽

pp. 8996

Author(s):

Renata Teparić ◽

Mateja Lozančić ◽

Vladimir Mrša

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Individual Component ◽

Building Blocks ◽

Fungal Cell ◽

Environmental Signals ◽

Identification And Characterization ◽

Wall Components ◽

Fungal Cell Walls

Fungal cell walls are composed of a polysaccharide network that serves as a scaffold in which different glycoproteins are embedded. Investigation of fungal cell walls, besides simple identification and characterization of the main cell wall building blocks, covers the pathways and regulations of synthesis of each individual component of the wall and biochemical reactions by which they are cross-linked and remodeled in response to different growth phase and environmental signals. In this review, a survey of composition and organization of so far identified and characterized cell wall components of different yeast genera including Saccharomyces, Candida, Kluyveromyces, Yarrowia, and Schizosaccharomyces are presented with the focus on their cell wall proteomes.

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Activation of the Silkworm Cytokine by Bacterial and Fungal Cell Wall Components via a Reactive Oxygen Species-triggered Mechanism

Journal of Biological Chemistry ◽

10.1074/jbc.m705480200 ◽

2007 ◽

Vol 283 (4) ◽

pp. 2185-2191 ◽

Cited By ~ 53

Author(s):

Kenichi Ishii ◽

Hiroshi Hamamoto ◽

Manabu Kamimura ◽

Kazuhisa Sekimizu

Keyword(s):

Reactive Oxygen Species ◽

Cell Wall ◽

Reactive Oxygen ◽

Fungal Cell Wall ◽

Oxygen Species ◽

Fungal Cell ◽

Cell Wall Components ◽

Wall Components

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Invertebrate Immune Response to Fungal Cell Wall Components

Fungal Cell Wall and Immune Response - NATO ASI Series ◽

10.1007/978-3-642-76074-7_24 ◽

1991 ◽

pp. 317-329 ◽

Cited By ~ 4

Author(s):

P. Götz

Keyword(s):

Immune Response ◽

Cell Wall ◽

Fungal Cell Wall ◽

Fungal Cell ◽

Cell Wall Components ◽

Wall Components

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Screening and Antifungal Activity of a β-Carboline Derivative against Cryptococcus neoformans and C. gattii

International Journal of Microbiology ◽

10.1155/2019/7157845 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Kátia Santana Cruz ◽

Emerson Silva Lima ◽

Marcia de Jesus Amazonas da Silva ◽

Erica Simplício de Souza ◽

Andreia Montoia ◽

...

Keyword(s):

Cell Wall ◽

Candida Albicans ◽

Antifungal Activity ◽

Cryptococcus Neoformans ◽

Active Compound ◽

Cell Walls ◽

Human Fibroblasts ◽

Lead Compound ◽

Fungal Cell ◽

Fungal Cell Walls

Background. Cryptococcosis is a fungal disease of bad prognosis due to its pathogenicity and the toxicity of the drugs used for its treatment. The aim of this study was to investigate the medicinal potential of carbazole and β-carboline alkaloids and derivatives against Cryptococcus neoformans and C. gattii. Methods. MICs were established in accordance with the recommendations of the Clinical and Laboratory Standards Institute for alkaloids and derivatives against C. neoformans and C. gattii genotypes VNI and VGI, respectively. A single active compound was further evaluated against C. neoformans genotypes VNII, VNIII, and VNIV, C. gattii genotypes VGI, VGIII, and VGIV, Candida albicans ATCC 36232, for cytotoxicity against the MRC-5 lineage of human fibroblasts and for effects on fungal cells (cell wall, ergosterol, and leakage of nucleic acids). Results. Screening of 11 compounds revealed 8-nitroharmane as a significant inhibitor (MIC 40 μg/mL) of several C. neoformans and C. gattii genotypes. It was not toxic to fibroblasts (IC50 > 50 µg/mL) nor did it alter fungal cell walls or the concentration of ergosterol in C. albicans or C. neoformans. It increased leakage of substances that absorb at 260 nm. Conclusions. The synthetic β-carboline 8-nitroharmane significantly inhibits pathogenic Cryptococcus species and is interesting as a lead compound towards new therapy for Cryptococcus infections.

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Feeding the Walls: How Does Nutrient Availability Regulate Cell Wall Composition?

International Journal of Molecular Sciences ◽

10.3390/ijms19092691 ◽

2018 ◽

Vol 19 (9) ◽

pp. 2691 ◽

Cited By ~ 11

Author(s):

Michael Ogden ◽

Rainer Hoefgen ◽

Ute Roessner ◽

Staffan Persson ◽

Ghazanfar Khan

Keyword(s):

Cell Wall ◽

Plant Cell ◽

Nutrient Availability ◽

Cell Walls ◽

Plant Cell Wall ◽

Nutrient Status ◽

Cell Wall Composition ◽

Nutrient Sensing ◽

Tissue Type ◽

Wall Components

Nutrients are critical for plants to grow and develop, and nutrient depletion severely affects crop yield. In order to optimize nutrient acquisition, plants adapt their growth and root architecture. Changes in growth are determined by modifications in the cell walls surrounding every plant cell. The plant cell wall, which is largely composed of complex polysaccharides, is essential for plants to attain their shape and to protect cells against the environment. Within the cell wall, cellulose strands form microfibrils that act as a framework for other wall components, including hemicelluloses, pectins, proteins, and, in some cases, callose, lignin, and suberin. Cell wall composition varies, depending on cell and tissue type. It is governed by synthesis, deposition and remodeling of wall components, and determines the physical and structural properties of the cell wall. How nutrient status affects cell wall synthesis and organization, and thus plant growth and morphology, remains poorly understood. In this review, we aim to summarize and synthesize research on the adaptation of root cell walls in response to nutrient availability and the potential role of cell walls in nutrient sensing.

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