Analysis of the bacteria community in wild Cordyceps cicadae and its influence on the production of HEA and nucleosides in Cordyceps cicadae

Aims The purpose of this study was to investigate the bacterial community of wild Cordyceps cicadae and explore its effect on the production of N6-(2-hydroxyethyl)-adenosine (HEA) and three nucleosides in C. cicadae. Methods and results Illumina high-throughput sequencing technology was used to analyse the bacterial community in wild C. cicadae. After C. cicadae was isolated and bacteria were isolated from wild C. cicadae, we identified four bacterial strains that independently altered HEA and nucleoside production in a coculture with C. cicadae and four bacteria separately. After cocultivation, the HEA yield from C. cicadae increased markedly. The bacteria in wild C. cicadae did not produce HEA, and the levels of three nucleosides decreased significantly. Both 16S rRNA and community analyses showed close evolutionary relationships and high abundance ratios for the four selected bacterial strains. Conclusions Some bacteria exist in wild C. cicadae and have a high abundance ratio. Moreover, the isolated bacteria inhibited the growth of C. cicadae and prevented the production of HEA in axenic cultures. Significance and impact of the study We discuss the bacterial community in wild C. cicadae and provide a new way to increase HEA production in C. cicadae by coculture with bacterial strains isolated from wild C. cicadae.