The Interpretation of the Role of a Polyketide Synthase ClPKS18 in the Pathogenicity of Curvularia lunata

Zhixiang Lu; Shaoqing Wang; Kai Dou; Jianhong Ren; Jie Chen

doi:10.3389/fmicb.2022.853140

The Interpretation of the Role of a Polyketide Synthase ClPKS18 in the Pathogenicity of Curvularia lunata

Front Microbiol. 2022 May 24:13:853140. doi: 10.3389/fmicb.2022.853140. eCollection 2022.

Authors

Zhixiang Lu^{1

2}, Shaoqing Wang^{1

2}, Kai Dou^{1

2}, Jianhong Ren³, Jie Chen^{1

2

4}

Affiliations

¹ School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.
² State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, China.
³ Suzhou PANOMIX Biomedical Tech Co., Ltd., Suzhou, China.
⁴ Ministry of Agriculture Key Laboratory of Urban Agriculture (South), Shanghai Jiao Tong University, Shanghai, China.

Abstract

Plant pathogenic fungus Curvularia lunata (Wakker) Boedijn causes leaf spot diseases in several plants such as Oryza sativa, Sorghum bicolor (L.) Moench, and Capsicum frutescens. It has been spread worldwide, specifically in maize-growing regions. The polyketide synthase (PKS) plays a significant role in secondary metabolite production and its effect on virulence. The Clpks18 of C. lunata strongly correlated with its pathogenicity. The role of Clpks18 gene on the pathogenic activity of C. lunata remains unclear. Hence, in this study, we analyzed the importance of Clpks18 gene on the hyphae and conidial melanization and on the sporulation and hyphal growth. The deletion of Clpks18 gene reduced the production of methyl 5-(hydroxymethyl)furan-2-carboxylate toxin. The virulence of ΔClpks18 mutant was significantly reduced compared with the wild type. The metabolomics data revealed that (R)-(-)-mellein was a vital factor in the virulence of C. lunata. The (R)-(-)-mellein and the toxin produced by C. lunata were detected in the maize leaves during its infestation. In addition, the metabolomic analysis showed that the Clpks18 gene influences glycerolipid, non-ribosomal peptide biosynthesis, and its metabolism. This study demonstrates that the Clpks18 gene is important for the pathogenicity of C. lunata by influencing the complex metabolic network.

Keywords: Curvularia lunata; melanization; pathogenicity; polyketide synthase; toxin.