Disease relevance of Oomycetes

• Zwittermicin A represents a new chemical class of antibiotic and has diverse biological activities, including suppression of oomycete diseases of plants and potentiation of the insecticidal activity of Bacillus thuringiensis [1].
• Atlantic menhaden Brevoortia tyrannus develop characteristic skin ulcers in response to infection by the oomycete Aphanomyces invadans [2].
• Zwittermicin A was highly active against the Oomycetes and their relatives, the algal protists, and had moderate activity against diverse Gram-negative bacteria and certain Gram-positive bacteria as well as against a wide range of plant pathogenic fungi [3].
• When zwittermicin A was combined with kanosamine, another antibiotic produced by B. cereus, the two acted synergistically against Escherichia coli and additively against Phytophthora medicaginis, an Oomycete [3].

High impact information on Oomycetes

• In a screen for suppressors of npr1-5-based salicylic acid (SA) insensitivity, we isolated a semidominant gain-of-function mutation, designated ssi4, that confers constitutive expression of several PR (pathogenesis-related) genes, induces SA accumulation, triggers programmed cell death, and enhances resistance to bacterial and oomycete pathogens [4].
• RPP8 confers resistance to an oomycete pathogen, Peronospora parasitica [5].
• In the Arabidopsis accession Wassilewskija, the RPP1 region on chromosome 3 contains four genetically linked recognition specificities, conditioning resistance to different isolates of the biotrophic oomycete Peronospora parasitica (downy mildew) [6].
• Elicitins and lipid-transfer proteins are small cysteine-rich lipid-binding proteins secreted by oomycetes and plant cells, respectively, that share some structural and functional properties [7].
• We report here that one of two Achlya H3 histones (H3.1) and also the oomycete histone alpha appear to be highly phosphorylated with heat shock [8].

Biological context of Oomycetes

• Cell cycle regulator Cdc14 is expressed during sporulation but not hyphal growth in the fungus-like oomycete Phytophthora infestans [9].
• In the filamentous oomycete fungus Achlya, the differentiation of gamete bearing structures on vegetative hyphae of the male mating type, is induced by the Achlya steroid hormone, antheridiol [10].
• The deduced amino acid sequence is equally similar to yeast and maize Hsp70, providing further evidence of the dissimilarity between Oomycetes and true fungi [11].
• Surrounding the primer-extension determined transcription start site of each A. ambisexualis hsp90 gene was a 16-nucleotide sequence that matched in 14 out of 16 nucleotides a sequence found in the transcription initiation region of many different oomycete genes [12].
• A beta4 integrin-like protein co-localises with a phosphotyrosine containing protein in the oomycete Achlya bisexualis: inhibition of tyrosine phosphorylation slows tip growth [13].

Anatomical context of Oomycetes

• A gradient of the divalent cation ionophore A23187 polarized axis establishment in regenerating hyphal protoplasts and germinating cysts of the tip-growing oomycete Saprolegnia ferax [14].
• Laboratory studies were conducted to evaluate the risk of developing field resistance to zoxamide, a new Oomycete fungicide which acts on microtubules [15].

Associations of Oomycetes with chemical compounds

• Phytophthora sojae (Kaufmann and Gerdemann) is an oomycete that causes stem and root rot on soybean (Glycine max L. Merr) plants [16].
• Plant pathogenic oomycetes, such as the potato (Solanum tuberosum) and tomato (Lycopersicon esculentum) pathogen Phytophthora infestans, secrete a diverse family of serine protease inhibitors of the Kazal family [17].
• By contrast, cryptogein, a sterol carrier protein from the Oomycete Phytophtora cryptogea, greatly increased absorption [18].
• Kanosamine was highly inhibitory to growth of plant-pathogenic oomycetes and moderately inhibitory to certain fungi and inhibited few bacterial species tested [19].
• The deduced sequence of the necrosis-inducing protein (Nip) showed homology to necrosis- and ethylene-inducing elicitors of fungi and oomycetes [20].

Gene context of Oomycetes

• These features classify RPS4 as a member of the TIR-NBS-LRR R gene family founded by N, L6 and RPP5, which determine resistance to viral, fungal and oomycete pathogens, respectively [21].
• A functional role for PCC1 in plant defence was demonstrated since plants overexpressing PCC1 are resistant against normally virulent oomycetes [22].
• Furthermore, the mos6-1 single mutant exhibited enhanced disease susceptibility to a virulent oomycete pathogen [23].
• GSII cDNA sequences were obtained from two species of oomycetes by polymerase chain reaction amplification [24].
• Nematodes, amoebas, ciliates, apicomplexans, and oomycetes express an alternative DBP with the SCP-2 domain directly connected to the D-3-hydroxyacyl-CoA dehydrogenase [25].

Analytical, diagnostic and therapeutic context of Oomycetes

• Grapevine (Vitis vinifera cv. Monastrell) suspension cell cultures were treated with fosetyl-A1, a widely used systemic fungicide for grapevine diseases caused by oomycetes, and examined at the electron microscope level for peroxidase cytochemistry [26].

References