Improvement of gibberellin production by a newly isolatedFusarium fujikuroimutant

Abstract

Aims To obtain and investigate the potential mechanism for GA3 production in Fusarium fujikuroi GA‐251, a high GA3 producer. Methods and Results Fusarium fujikuroi IMI 58289 was bred with Cobalt‐60 (60Co) radiation and lithium chloride treatment. The best mutant strain GA‐251 was obtained for the subsequent optimization of fermentation conditions. The yield of GA3 by GA‐251 was 2100 mg l−1, while the wild‐type strain was 100 mg l−1, which is a 21‐fold increase in the yield. To elucidate the mechanism of high GA3 yield of GA‐251, the genome was sequenced and compared with wild‐type strain IMI 58289. The results showed 2295 single nucleotide polymorphisms, 1242 small indels and 30 structural variants. These mutations were analysed and enriched in the MAPK signalling pathway, the mRNA surveillance pathway and endocytosis. The potential reasons for the improved GA3 biosynthesis were investigated. Conclusions The potential mechanism of high GA3 yield was attributed to endocytosis pathway and histone modification proteins family. Significance and Impact of the Study A mutant strain GA‐251 in this work that could potentially be utilized in the industrial yield of GA3. The comparative genome analysis would shed light onto the mechanism of yield improvement and be a theoretical guide for further metabolic engineering.

RETRACTED ARTICLE: Mutagenesis combined with fermentation optimization to enhance gibberellic acid GA3 yield in Fusarium fujikuroi

“…However, CRISPR/Cas9 was operated complexly and less reported at present. In recent years, microbial mutation breeding techniques have been regarded as an efficient tool to improve phenotypes or functions of strains, thus increasing products titer (Kodym and Afza 2003 ; Zhang et al 2020 ) . For example, mutants with different morphologies and mycelium colors were obtained by UV mutagenesis.…”

Bioprocess of Gibberellic Acid by Fusarium fujikuroi: The Challenge of Regulation, Raw Materials, and Product Yields

“…As shown, the generated knowledge about regulatory circuits for GA 3 biosynthesis opened new opportunities to perform mutations and genetic modifications, enabling researchers to carry out profound analyses for explaining the effects observed on metabolism. This is the case for the work developed by Zhang et al (2020), where mutation improvement in GA 3 producers was explained by genome sequencing, finding that genes involved in endocytosis, the MAPK signaling pathway, and histone modifications were responsible for the increased production of GA 3 [72].…”

“…This available information has allowed that different works can be focused on the use of raw materials with the purpose of solving two problems, the increase of GA 3 production and the waste utilization of residues from different agro-industries. The most employed raw materials are starch [ 68 ], corn flour [ 69 ], wheat bran [ 70 ], rice bran [ 7 ], barley flour, citrus pulp [ 71 ], corn starch [ 72 ], rice flour [ 8 ], and soybean flour [ 73 ], among others.…”

Establishment of a selectable marker recycling system for iterative gene editing in Fusarium fujikuroi

“…Currently, industrial production of GA3 relies on the fermentation of the filamentous fungus F. fujikuroi , which is renowned for its high-level production of GA3 [ 8 ]. In the past few decades, medium optimization and strain mutagenesis have been commonly employed strategies to enhance the titer of gibberellic acids [ [9] , [10] , [11] , [12] , [13] ]. However, these methods often involve a lengthy process with limited improvement in yield, which has led researchers to seek alternative approaches.…”