Hydrogen sulfide maintains redox homeostasis and suppresses ganoderic acids biosynthesis under heat stress via persulfidating thioredoxin 1 in Ganoderma lucidum.

Hydrogen sulfide (H2S) is regarded as a novel gaseous signalling molecule with multiple physiological functions. Recently, the identification of persulfidated proteins has become a new hotspot in the analysis of the underlying mechanism of H2S. The preliminary findings of our study indicate that H2S exerts a negative regulatory effect on the heat-induced accumulation of ganoderic acids (GAs), a major secondary metabolite in Ganoderma lucidum. However, a comprehensive understanding of its mechanism is lacking. In this study, the persulfidated proteins in G. lucidum were identified by means of quantitative proteomic mass spectrometry, and the role of H2S in maintaining redox homeostasis under heat stress conditions was determined. A redox-regulated protein, thioredoxin 1 (Trx1), was identified as a potential regulation mechanism of H2S in G. lucidum. Further research revealed that the activity of Trx1 was provoked by persulfidation at Cys31 and Cys34, contributing to the negative regulation of H2S to ROS accumulation and GAs biosynthesis under heat stress in G. lucidum. This study presents a new understanding of the physiological function and regulation mechanism of H2S in G. lucidum, offering a deeper understanding of the interaction mechanism between the H2S and ROS signalling pathways within the organism.