<p>In-vitro Detection of Phytopathogenic Fungal Cell Wall by Polyclonal Sera Raised Against Trimethyl Chitosan Nanoparticles</p>

ABSTRACT The fungal cell wall is a complex and dynamic entity essential for the development of fungi. It is composed mainly of polysaccharides that are synthetized by protein complexes. At the cell wall level, enzyme activities are involved in postsynthesis polysaccharide modifications such as cleavage, elongation, branching, and cross-linking. Glycosylphosphatidylinositol (GPI)-anchored proteins have been shown to participate in cell wall biosynthesis and specifically in polysaccharide remodeling. Among these proteins, the DFG family plays an essential role in controlling polar growth in yeast. In the filamentous fungus and opportunistic human pathogen Aspergillus fumigatus, the DFG gene family contains seven orthologous DFG genes among which only six are expressed under in vitro growth conditions. Deletions of single DFG genes revealed that DFG3 plays the most important morphogenetic role in this gene family. A sextuple-deletion mutant resulting from the deletion of all in vitro expressed DFG genes did not contain galactomannan in the cell wall and has severe growth defects. This study has shown that DFG members are absolutely necessary for the insertion of galactomannan into the cell wall of A. fumigatus and that the proper cell wall localization of the galactomannan is essential for correct fungal morphogenesis in A. fumigatus. IMPORTANCE The fungal cell wall is a complex and dynamic entity essential for the development of fungi. It is composed mainly of polysaccharides that are synthetized by protein complexes. Enzymes involved in postsynthesis polysaccharide modifications, such as cleavage, elongation, branching, and cross-linking, are essential for fungal life. Here, we investigated in Aspergillus fumigatus the role of the members of the Dfg family, one of the 4 GPI-anchored protein families common to yeast and molds involved in cell wall remodeling. Molecular and biochemical approaches showed that DFG members are required for filamentous growth, conidiation, and cell wall organization and are essential for the life of this fungal pathogen.

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Localization of fungal fimbriae by immunocytochemistry in pathogenic and nonpathogenic isolates of Venturia inaequalis

Canadian Journal of Microbiology ◽

10.1139/w00-061 ◽

2000 ◽

Vol 46 (9) ◽

pp. 800-808 ◽

Cited By ~ 2

Author(s):

Antonet M Svircev ◽

Ronald J Smith ◽

Ting Zhou ◽

Alan W Day

Keyword(s):

Cell Wall ◽

Venturia Inaequalis ◽

Fungal Cell Wall ◽

Fungal Mycelium ◽

Fungal Cell ◽

Transmission Electron ◽

Developmental Growth ◽

Large Central Vacuole ◽

Cellular Organelles

Pathogenic and nonpathogenic isolates of Venturia inaequalis were grown in liquid culture. Hyphae were treated with two types of fimbrial antiserum (AU- and AV-1) and examined by immunofluorescent microscopy, in order to establish the distribution of fimbrial epitopes in whole cell mounts. The AV-1 antiserum was specific for the glycoprotein subunits while the AU- antiserum was specific for the protein moieties present on the fimbriae of Mycobotryum violaceum. The use of fimbrial antiserum with immunocytochemistry and transmission electron microscopy demonstrated a clear distinction between pathogenic and nonpathogenic isolates of V. inaequalis, based on the appearance of the fungal cell wall and the distribution of fimbrial epitopes labeled with AV-1 antiserum and immunogold complex. In actively growing hyphae of the pathogenic isolate, characterized by distinct cellular organelles, small vacuoles, and lipid bodies, fimbrial epitopes were concentrated in the fungal cell wall and were present minimally on the outer surface. In contrast, actively growing hyphae of the nonpathogenic isolate of V. inaequalis had extensive fine hair-like protrusions in the fungal cell wall which labeled with the AV-1 antiserum and immunogold. The distribution of fimbrial epitopes in V. inaequalis was highly dependent on the developmental growth stage of the fungal mycelium. Aging mycelia in both the pathogenic and nonpathogenic isolates of V. inaequalis were characterized by a large central vacuole and no label. In the pathogenic and nonpathogenic isolates of V. inaequalis grown in vitro, the distribution of fimbrial glycoprotein epitopes provided a more complex profile than that seen in M. violaceum.Key words: fimbriae, immunocytochemistry, Venturia inaequalis, Mycobotryum violaceum.

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In vitro antifungal activity of new series of homoallylamines and related compounds with inhibitory properties of the synthesis of fungal cell wall polymers

Bioorganic & Medicinal Chemistry ◽

10.1016/s0968-0896(02)00605-3 ◽

2003 ◽

Vol 11 (7) ◽

pp. 1531-1550 ◽

Cited By ~ 81

Author(s):

Leonor Y Vargas M ◽

Marı́a V Castelli ◽

Vladimir V Kouznetsov ◽

Juan M Urbina G ◽

Silvia N López ◽

...

Keyword(s):

Cell Wall ◽

Antifungal Activity ◽

Fungal Cell Wall ◽

Fungal Cell ◽

Cell Wall Polymers ◽

Related Compounds ◽

In Vitro Antifungal Activity

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Faculty Opinions recommendation of Conserved processes and lineage-specific proteins in fungal cell wall evolution.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1147492.604672 ◽

2009 ◽

Author(s):

Jose Ruiz-Herrera

Keyword(s):

Cell Wall ◽

Fungal Cell Wall ◽

Fungal Cell ◽

Specific Proteins

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Faculty Opinions recommendation of Co-delivery of cell-wall-forming enzymes in the same vesicle for coordinated fungal cell wall formation.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726695262.793525615 ◽

2016 ◽

Author(s):

Meritxell Riquelme

Keyword(s):

Cell Wall ◽

Fungal Cell Wall ◽

Cell Wall Formation ◽

Fungal Cell ◽

Wall Formation

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Recent Status and Advancements in the Development of Antifungal Agents: Highlights on Plant and Marine Based Antifungals

Current Topics in Medicinal Chemistry ◽

10.2174/1568026619666190412102037 ◽

2019 ◽

Vol 19 (10) ◽

pp. 812-830 ◽

Cited By ~ 2

Author(s):

P. Marie Arockianathan ◽

Monika Mishra ◽

Rituraj Niranjan

Keyword(s):

Cell Wall ◽

Antifungal Agents ◽

Fungal Diseases ◽

Fungal Cell Wall ◽

Fungal Resistance ◽

Ergosterol Biosynthesis ◽

Fungal Cell ◽

Ergosterol Synthesis ◽

Glucan Synthesis ◽

Anti Fungal

The developing resistance in fungi has become a key challenge, which is being faced nowadays with the available antifungal agents in the market. Further search for novel compounds from different sources has been explored to meet this problem. The current review describes and highlights recent advancement in the antifungal drug aspects from plant and marine based sources. The current available antifungal agents act on specific targets on the fungal cell wall, like ergosterol synthesis, chitin biosynthesis, sphingolipid synthesis, glucan synthesis etc. We discuss some of the important anti-fungal agents like azole, polyene and allylamine classes that inhibit the ergosterol biosynthesis. Echinocandins inhibit β-1, 3 glucan synthesis in the fungal cell wall. The antifungals poloxins and nikkomycins inhibit fungal cell wall component chitin. Apart from these classes of drugs, several combinatorial therapies have been carried out to treat diseases due to fungal resistance. Recently, many antifungal agents derived from plant and marine sources showed potent activity. The renewed interest in plant and marine derived compounds for the fungal diseases created a new way to treat these resistant strains which are evident from the numerous literature publications in the recent years. Moreover, the compounds derived from both plant and marine sources showed promising results against fungal diseases. Altogether, this review article discusses the current antifungal agents and highlights the plant and marine based compounds as a potential promising antifungal agents.

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