Identification of phosphatidic acid interacting proteins in Ganoderma lingzhi / 生物工程学报

Ganoderma lingzhi is widely recognized as a medicinal basidiomycetes. Triterpene acids (TAs) are the key bioactive medicinal components of G. lingzhi. Our previous studies have shown that phospholipid acid (PA) produced by phospholipase D (PLD) plays a regulatory role in TA synthesis. In order to further elucidate the molecular mechanism how PA regulates TA synthesis in G. lingzhi, PA beads enrichment combined with LC-MS/MS technology was used to identify PA interacting proteins in G. lingzhi. A total of 19 PA interacting proteins were identified, including cytochrome P450 monooxygenase (GL22084), specific protein kinase MAPK (GL23765), catalase and cell surface hydrophobicity-associated protein. GST tagged GL22084 and GL23765 proteins were obtained through gene cloning, heterologous expression, and purification. The interactions between GL22084/GL23765 and PA were verified by GST pull down assay. The identification of PA interacting proteins provides a basis for further understanding the molecular mechanism how PLD-mediated PA signaling molecules regulates the TA synthesis in G. lingzhi. Moreover, the PA interacting proteins identified in this study can also provide clues for the research of PLD/PA signaling pathway in other species.

Taxonomic Position and Species Identity of the Cultivated Yeongji 'Ganoderma lucidum' in Korea

Ganoderma lucidum has a long history of use as a traditional medicine in Asian countries. However, the taxonomy of Ganoderma species remains controversial, since they were initially classified on the basis of their morphological characteristics. Recently, it was proposed that G. lucidum from China be renamed as G. sichuanense or G. lingzhi. In the present study, phylogenetic analysis using the internal transcribed spacer region rDNA sequences of the Ganoderma species indicated that all strains of the Korean 'G. lucidum' clustered into one group together with G. sichuanense and G. lingzhi from China. However, strains from Europe and North American, which were regarded as true G. lucidum, were positioned in a clearly different group. In addition, the average size of the basidiospores from the Korean cultivated Yeongji strains was similar to that of G. lingzhi. Based on these results, we propose that the Korean cultivated Yeongji strains of 'G. lucidum' should be renamed as G. lingzhi.