On August 24, 2018, professor Zhonghua Ma’s group published an article entitled “Wheat microbiome bacteria can reduce virulence of a plant pathogenic fungus by altering histone acetylation” in the journal 《Nature Communications》. This study revealed a new mechanism that the biocontrol bacteria in the microbiome can inhibit the growth, development and pathogenicity of pathogenic fungi, through regulating the histone modification of these fungi. It may provide new strategies for the biological control of plant fungal diseases.          

In recent years, wheat scab caused by the Fusarium graminearium complex is becoming more and more serious in China. The epidemic of the disease not only causes serious yield loss, but also brings about mycotoxins problems which impair the wheat quality. Due to the lack of disease-resistant wheat varieties and effective chemical fungicides, biological control strategies are expected to become an important way for the ecological management of this pathogen.

By combining the screening a large number of microbiome bacetria and evaluating their biocontrol effect in the field, professor Zhonghua Ma’s group isolated a highly effective biocontrol bacteria ZJU60 from the wheat ear microbiome. According to the genome sequencing result, the genetic and biochemical studies on ZJU60, the research group found that ZJU60 is a subspecies of Pseudomonas piscium. ZJU60 can secret a compound (phenazine-1-carboxamide) which directly affects the activity of fungal protein FgGcn5, a histone acetyltransferase of the SAGA complex. This leads to deregulation of histone acetylation in F. graminearum, as well as suppression of fungal growth, virulence, and mycotoxin biosynthesis. Therefore, this study not only proved that an antagonistic bacterium can inhibit growth and virulence of a plant pathogenic fungus by manipulating fungal histone modification, but also built a system for studying the interaction between bacteria and fungi.

Yun Chen, an associate professor of the team, is the first author of the paper, and the PhD student Jing Wang is the co-first author, Professor Zhonghua Ma and Yun Chen are the corresponding authors for this article. Yunrong Chai, the associate professor from the Northeast University of USA, also joined this research. This research has been supported by the foundation for distinguished young scholars of Zhejiang province, the national science foundation for distinguished young scholars, and the science youth entrustment project of China.

Model for the interaction between ZJU60 and Fusarium graminearium.