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Several Fungi (several + fungus)
Selected AbstractsInstruments of the warning service for plant protection in Bayern (Germany),EPPO BULLETIN, Issue 1 2000H. Tischner The warning service for plant protection in Bayern (Germany) obtains its information mainly from its own observations. The appearance of pests (including diseases and weeds) is investigated in cultivated areas and field trials. Weather data complementary to the pest enquiries can be made available from a measuring network of 116 field weather stations and is used to estimate the development of pests in relation to weather requirements. For several fungi and animal pests, computer-based decision support systems (DSSs) and forecasting models are being used. The results are processed and passed on to farmers via circulars, branch reviews, public notices, telephonic announcement services, telefax services and the Internet. [source] Detection and characterization of the novel bacteriocin entomocin 9, and safety evaluation of its producer, Bacillus thuringiensis ssp. entomocidus HD9JOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2003A. Cherif Abstract Aims: To identify and characterize new bacteriocins from a collection of 41 strains belonging to 27 subspecies of Bacillus thuringiensis, and to evaluate the safety of the producers. Methods and Results:Bacillus thuringiensis ssp. entomocidus HD9 produced in the culture supernatant an antimicrobial activity against Gram-positive bacteria including Listeria monocytogenes, one of four pathogenic Pseudomonas aeruginosa and several fungi. Production of the antibacterial activity, named entomocin 9, started during mid-logarithmic growth reaching its maximum at the early stationary phase. Entomocin 9 retained more than 72% of activity after incubation for 20 min at 121°C. Activity was lost after proteinase K treatment, it was stable in a pH range between 3 and 9, and resistant to lyophilization. After partial purification with ammonium sulphate precipitation followed by gel-filtration and anion-exchange chromatography, an active protein of ca 12·4 kDa was isolated. The mode of action of entomocin 9 was bactericidal and caused cell lysis of growing cells. Despite the presence of a range of virulence related genes, including haemolysin BL, nonhaemolytic enterotoxin, cytotoxin K and several hydrolytic activities, B. thuringiensis HD9 was not toxic against Vero cells. Conclusions: Entomocin 9 is a novel heat-stable, bacteriocin produced by B. thuringiensis HD9. The absence of toxicity against Vero cells suggests the suitability of strain HD9 for a safe application in antimicrobial treatments. Significance and Impact of the Study: New finding on entomocin 9 would make B. thuringiensis attractive in biotechnological applications as an antimicrobial agent in agriculture and food industry. [source] In vitro fungitoxic activity of Larrea divaricata cav. extractsLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2004E.N. Quiroga Abstract Aims:, To evaluate the fungitoxic activity of Larrea divaricata Cav. extract and one of its components against yeasts and fungi. This activity was compared with the action of ketoconazole, a known synthetic antimycotic. Methods and Results:, Antifungal activity of Larrea divaricata extract and of a fraction (Fr. B) purified by thin layer chromatography, was investigated using different methodologies. Both exhibited strong activity against the majority of the assayed fungi. Only Fusarium oxysporum and Schizophyllum commune growth was not affected with the assayed conditions. The fungitoxic and cytotoxic activity of the ethanolic extract and ketoconazole were compared. Conclusions:, Ethanolic extracts of L. divaricata Cav. produce growth inhibition of several fungi. One of its constituents with the same activity was purified and identified as a glycoside of a flavanone. A comparison with the action of ketoconazole, which is currently used as antimycotic and can cause adverse health effects was made. Significance and Impact of the Study:, Our data suggest that L. divaricata extract contains, at least, one compound of phenolic nature, with fungitoxic potency against yeasts and fungi. [source] Stable isotope dilution analysis of the Fusarium mycotoxins deoxynivalenol and 3-acetyldeoxynivalenolMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 3 2006Michael Bretz Abstract Trichothecenes are secondary metabolites produced by several fungi of the Fusarium genus during their growth period. They inhibit protein biosynthesis in eukaryotic cells resulting in numerous toxic effects such as diarrhea, vomiting, and gastro-intestinal inflammation. Considering its occurrence in food and feedstuff, deoxynivalenol (DON) is one of the most important trichothecenes. We report the synthesis of stable isotope labeled 15- d1 -deoxynivalenol (15- d1 -DON) from its natural precursor 3-acetyldeoxynivalenol (3-AcDON) as starting material. Furthermore, a method for the analysis of DON and 3-AcDON using HPLC-MS/MS with stable isotope labeled 15- d1 -DON and 3- d3 -AcDON as internal standards has been developed. In total, 18 cereal product samples were analyzed with contamination levels ranging from 10,301 ,g/kg for DON and 5,14 ,g/kg for 3-AcDON. This is the first report of an isotope dilution MS method for the analysis of type B-trichothecenes. [source] The Nep1-like proteins,a growing family of microbial elicitors of plant necrosisMOLECULAR PLANT PATHOLOGY, Issue 4 2004CLARE L. PEMBERTON SUMMARY A novel family of microbial elicitors of plant necrosis has been identified. Designated Nep1-like proteins (NLPs), after the first family member isolated, they range from 24 to 26 kDa and are found in a variety of taxonomically unrelated micro-organisms. These include several fungi and oomycetes, as well as Gram-positive and Gram-negative bacteria. Some NLPs induce a hypersensitive-like response in plants, although the basis for initiation of this response remains unclear. Similarly, the cellular role of such highly conserved proteins is undetermined. It is not clear whether the NLPs are dedicated elicitors of plant defences or whether this induction occurs as a result of another activity. [source] Fungal endophytes in a 400-million-yr-old land plant: infection pathways, spatial distribution, and host responsesNEW PHYTOLOGIST, Issue 3 2007Michael Krings Summary ,,The Early Devonian Rhynie chert has been critical in documenting early land plant,fungal interactions. However, complex associations involving several fungi that enter into qualitatively different relationships with a single host plant and even interact with one another have not yet been detailed. ,,Here, we studied petrographic thin sections of the Rhynie chert plant Nothia aphylla. ,,Three fungal endophytes (co)occur in prostrate axes of this plant: narrow hyphae producing clusters of small spores; large spherical spores/zoosporangia; and wide aseptate hyphae that form intercellular vesicles in the cortex. Host responses on attack include bulging of infected rhizoids, formation of encasement layers around intracellular hyphae, and separation of infected from uninfected tissues by secondarily thickened cell walls. ,,A complex simultaneous interaction of N. aphylla with three endophytic fungi was discovered. The host responses indicate that some of the mechanisms causing host responses in extant plants were in place 400 million yr ago. Anatomical and life history features of N. aphylla suggest that this plant may have been particularly susceptible to colonization by fungi. [source] Identification of four proteins from the small subunit of the mammalian mitochondrial ribosome using a proteomics approachPROTEIN SCIENCE, Issue 3 2001Emine Cavdar Koc Abstract Proteins in the small subunit of the mammalian mitochondrial ribosome were separated by two-dimensional polyacrylamide gel electrophoresis. Four individual proteins were subjected to in-gel Endoprotease Lys-C digestion. The sequences of selected proteolytic peptides were obtained by electrospray tandem mass spectrometry. Peptide sequences obtained from in-gel digestion of individual spots were used to screen human, mouse, and rat expressed sequence tag databases, and complete consensus cDNAs for these species were deduced in silico. The corresponding protein sequences were characterized by comparison to known ribosomal proteins in protein databases. Four different classes of mammalian mitochondrial small subunit ribosomal proteins were identified. Only two of these proteins have significant sequence similarities to ribosomal proteins from prokaryotes. These proteins are homologs to Escherichia coli S9 and S5 proteins. The presence of these newly identified mitochondrial ribosomal proteins are also investigated in the Drosophila melanogaster, Caenorhabditis elegans, and in the genomes of several fungi. [source] | ||||||||||||||||||||||