AUTHOR=Lu Zhixiang , Wang Shaoqing , Dou Kai , Ren Jianhong , Chen Jie 

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

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.853140

DOI=10.3389/fmicb.2022.853140

ISSN=1664-302X

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