Degradation of Fungal Cell Walls by Lytic Enzymes of Trichoderma harzianum

Hyaline hyphae of Phomopsis become pigmented when exposed to short periods of light. Pigment was deposited in the form of melanin granules both within the cell wall and within mucilaginous excrescences that were developed irregularly over the hyphal surface. Analysis of the pigment showed it to have properties similar to that of "Dopa" melanin and to pigments previously isolated from fungal cell walls. Lysis of both hyaline and pigmented hyphal walls by means of lytic enzymes was minimal. It is suggested that the major role of melanin in this fungus is the protection of cellular organelles from harmful ionizing radiations.

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An Antifungal Exo-α-1,3-Glucanase (AGN13.1) from the Biocontrol Fungus Trichoderma harzianum

Applied and Environmental Microbiology ◽

10.1128/aem.67.12.5833-5839.2001 ◽

2001 ◽

Vol 67 (12) ◽

pp. 5833-5839 ◽

Cited By ~ 76

Author(s):

Hassane Ait-Lahsen ◽

Andrés Soler ◽

Manuel Rey ◽

Jesús de la Cruz ◽

Enrique Monte ◽

...

Keyword(s):

Antifungal Activity ◽

Carbon Source ◽

Trichoderma Harzianum ◽

Cell Walls ◽

Plant Pathogens ◽

Fungal Cell ◽

Fungal Plant Pathogens ◽

Fungal Cell Walls

ABSTRACT Trichoderma harzianum secretes α-1,3-glucanases when it is grown on polysaccharides, fungal cell walls, or autoclaved mycelium as a carbon source (simulated antagonistic conditions). We have purified and characterized one of these enzymes, named AGN13.1. The enzyme was monomeric and slightly basic. AGN13.1 was an exo-type α-1,3-glucanase and showed lytic and antifungal activity against fungal plant pathogens. Northern and Western analyses indicated that AGN13.1 is induced by conditions that simulated antagonism. We propose that AGN13.1 contributes to the antagonistic response of T. harzianum.

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Analysis of the β-1,3-Glucanolytic System of the Biocontrol Agent Trichoderma harzianum

Applied and Environmental Microbiology ◽

10.1128/aem.64.4.1442-1446.1998 ◽

1998 ◽

Vol 64 (4) ◽

pp. 1442-1446 ◽

Cited By ~ 62

Author(s):

Soledad Vázquez-Garcidueñas ◽

Carlos A. Leal-Morales ◽

Alfredo Herrera-Estrella

Keyword(s):

Trichoderma Harzianum ◽

Cell Walls ◽

Biocontrol Agent ◽

Glucanase Activity ◽

Fungal Cell ◽

Molecular Weights ◽

Cell Wall Lysis ◽

Host Cell Wall ◽

35 Kda Protein ◽

Fungal Cell Walls

ABSTRACT The biocontrol agent Trichoderma harzianum IMI206040 secretes β-1,3-glucanases in the presence of different glucose polymers and fungal cell walls. The level of β-1,3-glucanase activity secreted was found to be proportional to the amount of glucan present in the inducer. The fungus produces at least seven extracellular β-1,3-glucanases upon induction with laminarin, a soluble β-1,3-glucan. The molecular weights of five of these enzymes fall in the range from 60,000 to 80,000, and their pIs are 5.0 to 6.8. In addition, a 35-kDa protein with a pI of 5.5 and a 39-kDa protein are also secreted. Glucose appears to inhibit the formation of all of the inducible β-1,3-glucanases detected. A 77-kDa glucanase was partially purified from the laminarin culture filtrate. This enzyme is glycosylated and belongs to the exo-β-1,3-glucanase group. The properties of this complex group of enzymes suggest that the enzymes might play different roles in host cell wall lysis during mycoparasitism.

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Rapid determination of binding parameters of chitin binding domains using chitin-coated quartz crystal microbalance sensor chips

The Analyst ◽

10.1039/c8an01453a ◽

2018 ◽

Vol 143 (21) ◽

pp. 5255-5263 ◽

Cited By ~ 2

Author(s):

Stephan Vogt ◽

Marco Kelkenberg ◽

Tanja Nöll ◽

Benedikt Steinhoff ◽

Holger Schönherr ◽

...

Keyword(s):

Cell Walls ◽

Quartz Crystal ◽

Fungal Infections ◽

Rapid Determination ◽

Binding Parameters ◽

Fungal Cell ◽

Binding Domains ◽

Quartz Crystal Microbalance Sensor ◽

Fungal Cell Walls

Chitin present in fungal cell walls has been considered as a diagnostic polymer for the detection of fungal infections.

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Structure and Synthesis of Fungal Cell Walls

10.1017/9781108776387.007 ◽

2020 ◽

pp. 171-191

Keyword(s):

Cell Walls ◽

Fungal Cell ◽

Fungal Cell Walls

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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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