Time Course of Virus-like Particles (vlps) Double-stranded Rna Accumulation in Toxigenic and Non-toxigenic Strains of Aspergillus Flavus
نویسندگان
چکیده
Two strains of Aspergillus flavus, non-toxigenic NRRL 6550 and toxigenic NRRL 5940, were studied over a period of 44 days, in order to detect the presence of virus-like particles (VLPs) by means of electron microscopy (EM) and nucleic acids electrophoresis. Only the toxigenic strain contained VLPs, presenting three-segmented dsRNA. An increase in VLPs number was observed during the exponential phase of fungal growth, up to day 12 of culture; after this, higher levels of aflatoxin production in toxigenic NRRL 5940 mycelia occurred in parallel with decreased VLPs replication.
منابع مشابه
Expression of aflR, veA and laeA as regulators of aflatoxins and cyclopiazonic acid biosynthesis pathway in Aspergillus flavus
In this study, the production of aflatoxin B1 (AFB1) and cyclopiazonic acid (CPA) was investigated in toxigenic and non-toxigenic Aspergillus flavus with respect to expression of aflR, veA and laeA genes that are involved to toxins production. A. flavus strains were cultured in YES broth at 28 °C for 4 days and the presence of (AFB1) and (CPA) was confirmed and measured by TLC and HPLC. The exp...
متن کاملIdentification and Quantification of a Toxigenic and Non-Toxigenic Aspergillus flavus Strain in Contaminated Maize Using Quantitative Real-Time PCR
Aflatoxins, which are produced by Aspergillus flavus, are toxic to humans, livestock, and pets. The value of maize (Zea mays) grain is markedly reduced when contaminated with aflatoxin. Plant resistance and biological control using non-toxin producing strains are considered effective strategies for reducing aflatoxin accumulation in maize grain. Distinguishing between the toxin and non-toxin pr...
متن کاملGenetic diversity of environmental Aspergillus flavus strains in the state of São Paulo, Brazil by random amplified polymorphic DNA.
Aspergillus flavus is a very important toxigenic fungus that produces aflatoxins, a group of extremely toxic substances to man and animals. Toxigenic fungi can grow in feed crops, such as maize, peanuts, and soybeans, being thus of high concern for public health. There are toxigenic and non-toxigenic A. flavus variants, but the necessary conditions for expressing the toxigenic potential are not...
متن کاملPositive correlation exists between glutathione S-transferase activity and aflatoxin formation in Aspergillus flavus.
The presence of glutathione (GSH) S-transferase activity, using 1-chloro-2, 4-dinitrobenzene (CDNB) as a substrate, has been established in the cytosolic fraction of the toxigenic (aflatoxin producing) and nontoxigenic strains of Aspergillus flavus. Significant differences in the GSH S-transferase activity were observed between the toxigenic and non-toxigenic strains. A positive correlation has...
متن کاملTemporal Effects on Internal Fluorescence Emissions Associated with Aflatoxin Contamination from Corn Kernel Cross-Sections Inoculated with Toxigenic and Atoxigenic Aspergillus flavus
Non-invasive, easy to use and cost-effective technology offers a valuable alternative for rapid detection of carcinogenic fungal metabolites, namely aflatoxins, in commodities. One relatively recent development in this area is the use of spectral technology. Fluorescence hyperspectral imaging, in particular, offers a potential rapid and non-invasive method for detecting the presence of aflatoxi...
متن کامل