RESUMEN
Background: In Saccharomyces cerevisiae, Msn2, which acts as a key transcription factor downstream the MAPKHOG cascade pathway, also regulates the expression of genes related to stress responses. However, little is known about the regulation mechanisms of the transcription factor in Setosphaeria turcica. Results: In this study, a zinc finger DNA-binding protein, designated as StMSN2, was cloned from S. turcica. Sequencing results showed that StMSN2 had a 1752 bp open reading frame (ORF), which was interrupted by an intron (135 bp) and encoded a putative 538-amino acid protein. Phylogenetic analysis further revealed that StMsn2 was more closely related to Msn2 of Aspergillus parasiticus. StMSN2 was cloned into the pET-28a vector with His (Histidine) tags and induced with 1 mM IPTG (isopropyl-ß-D-thiogalactoside) at 37°C. The recombinant His-tagged StMsn2 was purified, and a band of size approximately 58.8 kDa was obtained. The high specificity of the polyclonal antibody Msn2-2 was detected with the StMsn2 protein from S. turcica and prokaryotic expression system, respectively. Conclusions: A new gene, named StMSN2, with 1617 bp ORF was cloned from S. turcica and characterized using bioinformatics methods. StMsn2 was expressed and purified in a prokaryotic system. A polyclonal antibody, named Msn2-2, against StMsn2 with high specificity was identified.
Asunto(s)
Enfermedades de las Plantas , Ascomicetos/genética , Ascomicetos/patogenicidad , Factores de Transcripción/aislamiento & purificación , Ascomicetos/metabolismo , Estrés Fisiológico , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Portadoras , Expresión Génica , Western Blotting , Sistemas de Lectura Abierta , Dedos de Zinc , Clonación Molecular , Zea mays , Escherichia coli , Helminthosporium , EpítoposRESUMEN
Twenty-four endophytic actinomycetes strains were isolated from the Salvia przewalskii in Tibetan Plateau of China by tablet coating method. Fusarium moniliforme, Helminthosporium turcicum and Bipolaris maydis were selected as indicator fungi to test the antimicrobial activities of these endophytic actinomycetes by tablet confrontation method. The results showed that 21 strains can produce antimicrobial substances which accounts for 85.7% of the total separates number. Four strains of endogenous actinomyces have more obvious antifungi activity. According to results of morphology and culture properties and 16S rDNA sequences of endophytic actinomyces, it is concluded that all of the isolates were streptomycetes trains.
Asunto(s)
Actinomyces , Química , Genética , China , ADN Ribosómico , Genética , Fusarium , Helminthosporium , Salvia , MicrobiologíaRESUMEN
The alkaloid securinine was assessed against spore germination of some plant pathogenic and saprophytic fungi (Alternaria alternata, Alternaria brassicae, Alternaria brassicicola, Curvularia lunata, Curvularia maculans, Curvularia pallenscens, Colletotrichum musae, Colletotrichum sp., Erysiphe pisi, Helminthosporium echinoclova, Helminthosporium spiciferum, Heterosporium sp.). Spore germinations of all the tested fungi were inhibited. Alternaria brassicicola, C. lunata, C. pallenscens and H. spiciferum were highly sensitive as complete inhibition of spore germination was observed at very low concentrations (200 ppm).
Asunto(s)
Alternaria , Azepinas , Brassica , Colletotrichum , Hongos , Germinación , Helminthosporium , Compuestos Heterocíclicos de Anillo en Puente , Lactonas , Musa , Phyllanthus , Piperidinas , Plantas , EsporasRESUMEN
1-Corydalmine,an alkaloid isolated from roots of Corydalis chaerophylla inhibited spore germination of some plant pathogenic as well as saprophytic fungi e.g. Alternaria brassicae, A. brassicicola, A. solani, Curvularia lunata, C. maculans, C. sp., C. pallscens, Erysiphe pisi, Fusarium udum, Helminthosporium species,H. penniseti and a Heterosporium species. 1-Corydalmine significantly inhibited spore germination of all the fungi at 100 to 1500 ppm. It was effective against all the fungi at 1500 ppm. C. lunata was highly sensitive to this chemical even at 250 ppm.
Asunto(s)
Alternaria , Brassica , Corydalis , Hongos , Fusarium , Germinación , Helminthosporium , Plantas , EsporasRESUMEN
Diseases caused in wheat by Helminthosporium spp. have led to considerable yield and production losses. Different species in this genus are associated with wheat seeds. In Brazil, spot blotch in wheat is caused by Bipolaris sorokiniana (Sacc) Schoem, and another fungus Bipolaris bicolor (Mitra) Shoem that has been also isolated from wheat seeds. The current study was undertaken to identify the most frequent fungus species that normaly infects wheat seeds and compared them with B. sorokiniana. The fungus Bipolaris bicolor (Mitra) Shoem., isolated from wheat seeds cultivar IAPAR, was identified by taxonomic methods and compared with the fungus Bipolaris sorokiniana (Sacc.) Shoem., in relation to growth characteristics on the seeds, as well as to growth characteristics in PDA and morphology of the structures. Type of colony observed on the seeds is important for the differentiation between the fungus species. Bipolaris sorokiniana presented black colonies, which were well-adherent to the seeds, whereas B. bicolor presented grayish, aerial, cotton-like colonies. The size of the conidia also differed in length and width, and B. bicolor presented the smallest dimensions. In relation to septa, B. bicolor conidia presented deep ones, with dark color bases, but seldom presented dark apex. Bipolaris sorokiniana presented homogenous color.
Doenças causadas por Helminthosporium spp. em trigo, causam consideráveis perdas na produção. Diferentes espécies do gênero do fungo podem ser encontradas em sementes. No caso do Brasil, a mancha foliar do trigo tem sido causada por Bipolaris sorokiniana (Sacc) Schoem, entretanto, outro fungo como Bipolaris bicolor (Mitra) Shoem tem sido isolado de sementes do trigo. O objetivo do presente trabalho foi identificar as espécies de fungo que normalmente infectam sementes de trigo e comparar com a mais comum B. sorokiniana. O fungo Bipolaris bicolor (Mitra) Shoem., isolado de sementes de trigo var. IAPAR, foi identificado por métodos taxonômicos e comparado com o fungo Bipolaris sorokiniana (Sacc.) Shoem. em relação ao crescimento sobre as sementes bem como às características culturais no meio BDA e morfologia das estruturas. O tipo de colônia observada sobre as sementes é importante para diferenciar as espécies entre si. O fungo B. sorokiniana apresentou colônias de cor preta sendo bem aderidas às sementes, enquanto B. bicolor apresentou colônias aéreas acinzentadas e com aspecto cotonoso. O tamanho dos conídios também diferenciaram no comprimento e largura onde os valores menores corresponderam a B. bicolor. Em relação aos septos, os conídios de B. bicolor apresentavam septo "profundo", com coloração escura na base e, raras vezes no ápice. Os conídios de B. sorokiniana apresentaram coloração homogênea.
Asunto(s)
Hongos , Helminthosporium , Técnicas In Vitro , Triticum , Brasil , Clasificación , Métodos , SemillasRESUMEN
Narceine methyl ester and narceine are potent alkaloids which were isolated from Corydalis longipes were found effective in vitro at very low concentration, i.e., 100~500 ppm against spore germination of some test plant pathogenic fungi (Alternaria solani, A. tagetica, Cercospora abelmoschi, Curvularia maculans, Erysiphe cichoracearum, E. pisi, Fusarium udum, Helminthosporium oryzae, H. penniseti, Ustilago cynodontis). Among the test, phytopathogens the spores of F. udum, C. maculans and H. penniseti were highly sensitive at 200 ppm. However, spores of E. pisi, A. solani and A. tagetica were less sensitive at low concentration followed by other test fungi. Most of the fungi showed zero or nearly zero percent spore germination at 400 and 500 ppm.
Asunto(s)
Alcaloides , Corydalis , Hongos , Fusarium , Germinación , Helminthosporium , Oryza , Plantas , Esporas , UstilagoRESUMEN
Crude extracts and active principles from medicinal plants have shown potential role in controlling plant diseases in glasshouses as well as in fields as one of the safest and ecofriendly methods. The effect of nor-securinine (an alkaloid) isolated from Phyllanthus amarus has been seen against spore germination of some fungi (Alternaria brassicae, A. solani, Curvularia pennisetti, Curvularia sp., Erysiphe pisi, Helminthosporium frumentacei) as well as pea powdery mildew (Erysiphe pisi) under glasshouse conditions. The sensitivity of fungi to nor-securinine varied considerably. Nor-securinine was effective against most of the fungi. H. frumentacei was more sensitive even at the lowest concentration (1,000 microg/ml). Likewise conidia of E. pisi were also inhibited in partially or completely appressorium formation. Pre-inoculation treatment showed greater efficacy than post-inoculation in inhibiting powdery mildew development on pea plants in a glasshouse. Maximum inhibition occurred at 2000 microg/ml
Asunto(s)
Brassica , Mezclas Complejas , Hongos , Germinación , Helminthosporium , Pisum sativum , Phyllanthus , Enfermedades de las Plantas , Plantas Medicinales , Esporas , Esporas FúngicasRESUMEN
The inhibitory activity of ent-norsecurinine alkaloid was evaluated against spore germination of some plant pathogenic fungi (Curvularia maculans, Curvularia species, C. palliscens, Colletotrichum gloeosporioides, Colletotrichum species, Alternaria solani, A. brassicae, Fusarium udum, Helminthosporium echinoclova and H. penniseti). It inhibited spore germination of all the test fungi. C. maculans, C. species, and C. palliscens were the most sensitive as complete inhibition of spore germination was observed at 1000 ppm. A. solani was not inhibited by this chemical.
Asunto(s)
Alternaria , Brassica , Colletotrichum , Hongos , Fusarium , Germinación , Helminthosporium , Plantas , EsporasRESUMEN
Chaerophylline and berberine hydroxide, both being alkaloids, isolated from Corydalis chaerophylla and C. longipes respectively were assayed against spore germination of some fungi, e.g. Alternaria solani, A. brassicola, A. brassicicola, Helminthosporium penniseti, Helminthosporium sp., Heterosporium sp., Curvularia penniseti, C. maculens and C. palliscens. While chaerophylline inhibited spore germination of most of the fungi at 1000 ppm, being also effective at 50, 100, 200 and 500 ppm, berberine hydroxide was significantly effective at much lower concentration, i.e., 400 ppm against several fungi. This compound was also effective against some fungi at 50, 100, 150, 200 ppm. There was 100% inhibition of spore germination in several fungi at highest concentration of both the compounds. Some of the fungi showed similar results even at lower concentrations.
Asunto(s)
Alcaloides , Alternaria , Berberina , Corydalis , Hongos , Germinación , Helminthosporium , EsporasRESUMEN
Mediante cultivos en cámara húmeda y agar agua, se estudió la presencia y distribución biogeográfica, del género curvularia y helminthosporium "complex", en 19 gramíneas silvestres recolectadas en 20 localidades de la V región, Chile. En los 88 aislamientos fúngicos, se detectaron los géneros: bipolaris (77,2 por ciento), curvularia (12,5 por ciento) y drechslera (10,2 por ciento). Bipolaris cynodontis (45,5 por ciento) y b. australiensis (27,3 por ciento), fueron las especies dominantes, mientras los integrantes de los géneros curvularia (c. lunata ( 1,1 por ciento) y c. affinis ( 1,1 por ciento) fueron esporádicas. Las gramíneas y localidades con mayor diversidad de especies fueron respectivamente: sorghum (5) y zea (3); Curacaví (6 taxa) y Quillota (3 taxa). Se efectuaron claves dicotómicas, se compararon algunas características morfofisiológicas de las especies dominantes y se revisó brevemente en la literatura algunas patologías humanas causadas por estas dematiáceas
Asunto(s)
Hongos/aislamiento & purificación , Helminthosporium/aislamiento & purificación , Medios de Cultivo , Hojas de la Planta/parasitología , Poaceae/parasitologíaRESUMEN
Se ha demostrado que cuando se produce un estrés en las células vegetales, se estimula o induce la producción de metabolitos secundarios; para lograr estos fines se han empleado, fundamentalmente, agentes químicos y biológicos. En el presente trabajo se adicionó un homogeneizado del hongo Helminthosporium sacharii a una suspensión celular de Catharanthus roseus (L) G Don, para observar su efecto sobre la estimulación de la producción de alcaloides en dicha especie vegetal. Se realizaron diversas determinaciones químicas y biológicas en el momento de la inoculación del hongo, y a los 4, 8 y 12 días posteriores a su inoculación. Los resultados evidenciaron un ligero incremento de la producción de alcaloides por la suspensión de C. roseus inoculada, observándose que la tetrahidroalstonina fue el alcaloide mayormente producido en todos los tiempos de incubación
Asunto(s)
Alcaloides/biosíntesis , Helminthosporium , Plantas Medicinales/efectos de los fármacosRESUMEN
The air-borne fungi are usually considered to be as non-pathogenic and saprophytic organisms. However, those can be causative factors of certain allergic disease, and produce mycotoxic diseases such as caused by aflatoxin B1,or opportunistic infections, since various kinds of antitumor agents and adrenocorticosteroids have been introduced to therapeutics, and those who are affected some malignant tumors or metabolic anomalous diseases. As the first step toward. understanding and controlling the diseases, the studies on the population of air-borne fungi seem to be necessary. Authors studied the fluctuations of population of air-borne fungi at monthly intervals from June 1974 through May 1975 and at various times of the day at different places in th hospital, and the results obtained were as follows: 1. The identified fungi species and the percentage of colony counts of each species were Hormodendrum sp. (37. 2% ), Penicillium sp. (18. 8% ), Aspergillus sp, (17. 6 % ), Alternaria sp. (6.3 %), Mycelia sterila (2.6 %), Paecilomyces sp. (1.2 %) RhodO torula sp. (1. 1 % ), Oospora, sp. (0, 7 % ), Rhizopus sp. (0. 6 %. ), Geotrichum sp. (0.4%), Monilia sp. (0.4%), Mucor sp. (0.4%), Trichoderma sp. (0.4%.), Trichosporon sp. (0. 1%), Stemphylium sp. (0. 1 % ), Helminthosporium sp. (0. 1%) Gliocladium sp. (0. 1,: ), Saccharomyces sp. (0. 1 % ), Trichothecium sp. (0. 03 % ), and other unknown species(11. 6%) in decreasing order of frequency. 2. The monthly fluctuations of number of cultured colonies of four major airborne fungi (Hormodendrum, Penicillium. Aspergillus, and Alternaria) were 649 in June, 105 in July, 372 in August, 431 in September, 188 in October, 241 in November and 89 in December 1974, and 92 in January, 115 in February, 77 in March, 178 in April and 116 in May 1975. 3. It was suggested that there might be a relationship among the humidity, the temperature and the population of the air-borne fungi because the abrupt drop in July seemed to be related to high level of tbe,humidity (86.8%) and the temyerature (24. 3'C). And since the total number of colonies decreased markedly in December 1974 and Junuary 1975, it seemed to be closely related to cold weather temperature. 4. The number of cultured colonies at various times of the day did not show much fluctuation, except that Aspergillus sp. showed sudden tremendous increase at. one occasion, at 3: 00 P.M. on 15th of June and that gradual increase of Hormodendrum sp. was noted on another occasion from 12: 00 A.M. on 15th of September. 5. With regard to the locations of sampling, such as the operating room, laboratory, ward and out-patient department in the hospital, the difference in the identified. fungi species, the number of colony counts and the relationship with the humidity A the temperature was not evident. Authors reviewed relevant literatures and made discussions also.