Succinylated acetyl-CoA carboxylase contributes to aflatoxin biosynthesis, morphology development, and pathogenicity in Aspergillus flavus

• Published in: International journal of food microbiology 2024-03, Vol.413, p.110585-110585, Article 110585
• Main Authors: Xie, Rui, Zhang, Bei, Tumukunde, Elisabeth, Zhuang, Zhenhong, Yuan, Jun, Wang, Shihua
• Format: Article
• Language: English
• Subjects: Acetyl-CoA carboxylase; Acetyl-CoA Carboxylase - genetics; Acetyl-CoA Carboxylase - metabolism; Aflatoxin; Aflatoxin B1; Aspergillus flavus; Aspergillus flavus - metabolism; Mutation; Pathogenicity; Succinylation; Virulence
• ISSN: 0168-1605; 1879-3460
• DOI: 10.1016/j.ijfoodmicro.2024.110585

Acetyl-CoA carboxylase (ACC), which catalyzes acetyl-CoA to produce malonyl-CoA, is crucial for the synthesis of mycotoxins, ergosterol, and fatty acids in various genera. However, its biofunction in Aspergillus flavus has not been reported. In this study, the accA gene was deleted and site-mutated to explore the influence of ACC on sporulation, sclerotium formation, and aflatoxin B1 (AFB1) biosynthesis. The results revealed that ACC positively regulated conidiation and sclerotium formation, but negatively regulated AFB1 production. In addition, we found that ACC is a succinylated protein, and mutation of lysine at position 990 of ACC to glutamic acid or arginine (accAK990E or accAK990R) changed the succinylation level of ACC. The accAK990E and accAK990R mutations (to imitate the succinylation and desuccinylation at K990 of ACC, respectively) downregulated fungal conidiation and sclerotium formation while increasing AFB1 production, revealing that the K990 is an important site for ACC's biofunction. These results provide valuable perspectives for future mechanism studies of the emerging roles of succinylated ACC in the regulation of the A. flavus phenotype, which is advantageous for the prevention and control of A. flavus hazards. •acetyl-CoA carboxylase, an enzyme that is responsible for catalyzing from acetyl-CoA to form malonyl-CoA.•We focus on the study of sporulation, sclerotium formation, and AFB1 production under the regulation of ACC in A. flavus.•ACC is a succinylated protein, and the mutation of K990 on ACC can change succinylaton level.•Site-directed mutation of K990 on ACC can affect A. flavus sporulation, sclerotium formation, and AFB1 biosynthesis.