Oomycetes fungi

Real fungi (Ascomycetes, Basidomycetes, Deuteromycetes) and lower fungi (Oomycetes)... 

Novel cyclohexenones, acremines A-F (109-114), were isolated from a mycoparasitic Acremonium sp. from the oomycete pathogen Plasmopara viticola on Vitis vinifera cv. Regina blanca. Compounds 109-112 inhibited germination of the pathogen, and the most activity was shown by acremine C (111). This work may lead to a mechanism for the mycocidal activity of mycoparasitic fungi. 

Schardl CL, Craven KD, Interspecific hybridization in plant-associated fungi and oomycetes A review, MolEcol 12 2861—2873, 2003. 

The Oomycetes, a class within the Phycomycetes, is unusual and regarded by many as being distinct from the true fungi. The taxonomic... 

Benzimidazoles are highly selective. Oomycete fungi are insensitive to the benzimidazoles, as are higher plants. The reason for the distinct differences in sensitivity is unknown but probably depends on single structural differences of the microtubule binding site. Resistance of this type, if stable, spreads rapidly and results in catastrophic disease control... 

This primary mode of action of tomatine, that involves the formation of complexes with membrane sterols is similar to that described for polyene antibiotics [2, 4], and results in pore formation and loss of membrane integrity. This mode of action is supported by the reduced activity of tomatine on sterol-free bacteria and Oomycete fungi such as Pythium and Phytophthora [15, 28], and the strongly reduced toxicity of hydrolysis products of the glycoalkaloid which fail to bind sterols [57]. 

Osmotrophs are organotrophic organisms that acquire nutrients from their environment one molecule at a time. Osmotrophs include most members of the bacteria and archaea domains, as well as fungi and several protistan groups. Except in association with coarse organic particles where eukaryotic fungi and oomycetes are prominent, prokaryotes dominate heterotrophic metabolism, so are the focus of the text that follows. We use the term bacteria loosely, recognizing that heterotrophic archaea may well be major consitituents of the microbial loop of many systems. 

Among the fungi, the class Oomycetes is by number the smallest of the five classes, comprising some 70 genera with 500 species. However, in many respects, they are a unique and important class 1) their cell walls differ from those of all other fungi, inasmuch as they contain cellulose instead of chitin 2) they do not synthesize sterols 3) their life cycle is diploid (in contrast to all other fungi) and 4) they form motile spores (zoospores). 

Professor Schwinn discussed new advances in the chemical control of plant parasitic Oomycetes and Peronosporales. Some of the most devastating foliar and root diseases are caused by these fungi, hut they are often not controlled by systemic fungicides which control... 

Differential Response of Fungi and Oomycetes to the Addition of Ginsenosides to Culture Media... 

Latijnhouwers, M., de Wit, P.J.G.M., Govers, F. Oomycetes and fungi similar weaponry to attack plants. Trends Microbiol, 2003 11 462-469. 

Use Controls disease caused by Oomycete class of fungi. 

Phenylamide fungicides selectively inhibit ribosomal RNA synthesis of sensitive Oomycete fungi by interference with the activity of the RNA polymerase I-template complex. 

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