A method for constructing a high-yield deoxynivalenol knockout mutant strain

Abstract

A construction method for a single knock-out mutant bacterial strain producing deoxynivalenol in a high-yield mode includes the following steps of firstly, knocking a negative regulatory factor high-affinity phosphodiesterase gene FgPDE2 generated in the fusarium graminearumout deoxynivalenol synthesis process out of a genome of fusarium graminearum PH-1 through a split-PCR method, and obtaining the single knock-out mutant, wherein the gene FgPDE2 and upstream and downstream sequences are shown in SEQ ID NO:1; secondly, PEG-mediated protoplast is converted into fusarium graminearum, knocking out converters through resistance screening and marker screening, and verifying that the target gene knocking out the converters is replaced with a neomycin resistance gene through primers 5F and 6R with the genome of fusarium graminearum serving as the reference. The toxicity production amount of the single knock-out mutant bacterial strain is greatly increased; the toxicity production amount of a double knock-out mutant bacterial strain is higher; the gene modification mutant loses the capacity for infecting wheatears, and negative effects caused by possible diffusion of the double knock-out mutant bacterial strain are greatly reduced.

Description

technical field [0001] The invention discloses a method for constructing a high-yield deoxynivalenol knockout mutant strain, in particular to a construction method for a high-yield Fusarium graminearum deoxynivalenol knockout mutant strain. Background technique [0002] Fusarium graminearum is the pathogenic fungus that causes Fusarium head blight or scab in wheat. It not only seriously affects crop yield, but also can produce a variety of mycotoxins deoxynivalenol (DON) that are harmful to humans and animals. Decreased quality of food or feed. Deoxynivalenol (deoxynivalenol, DON) is a sesquiterpene compound, which is not easy to degrade and has high stability. The main natural toxin is present in head blight-affected wheat. DON toxin is one of the mycotoxins with the highest pollution rate. It mainly contaminates cereal crops such as wheat and corn, and also contaminates food products, such as bread, biscuits, wheat-based snacks, etc. In addition, DON residues are also re...

AI Technical Summary

Problems solved by technology

However, the toxin-producing ability of Fusarium graminearum obtained in nature has little difference, and it is difficult to screen high-yield strains for large-scale production

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