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.

Effects of medicinal insect Catharsius molossus on submerged fermentation and in vivo anti-hepatoma activity of Ganoderma lucidum / 生物工程学报

We studied the effects of Catharsius molossus (a Chinese medicinal insect) on the cell growth, fermentation kinetics of key bioactive substances and anti-cancer activity of Ganoderma lucidum in submerged fermentation. The results showed that C. molossus at all the tested concentrations had no stimulatory effect on the cell growth. However, addition of C. molossus at 5 g/L lead to significant effects on the fermentation kinetics of polysaccharides and triterpenoids of G lucidum, and at 7th day in fermentation process, the yields of polysaccharides and triterpenoids reached 2.81 g/L and 539.0 mg/L, respectively, while they were 2.25 g/L and 428.2 mg/L in control. In vivo anti-cancer studies showed that the inhibitory rates of control fermented G lucidum (CFG) and a combination of water extract from C. molossus and CFG on the developed tumor (Heps) in mice were 41.61% and 42.24%, respectively. Moreover, the inhibitory rate of the G lucidum fermented with C. molossus (GFC) reached 57.21%, which was enhanced 37.49%, compared to the inhibitory rate of the control fermented G lucidum. These results suggest that supplementation of C. molossus in submerged fermentation of G lucidum lead to a significant enhancement of the anti-cancer activity of cultured G lucidum.

Effects of medicinal insect, Catharsius molossus on biosynthesis of polysaccharides from Ganoderma lucidum in submerged culture / 生物工程学报

We studied the effects of several medicinal insects on biosynthesis of polysaccharides from Ganoderma lucidum in submerged culture. The results showed that the medicinal insect, Catharsius molossus at 5 g/L significantly promoted the biosynthesis of intracellular polysaccharides (IPS) and extracellular polysaccharides (EPS) of G. lucidum, and compared with control, IPS and EPS yields markedly enhanced from (1.93 +/- 0.09) g/L to (2.41 +/- 0.12) g/L and (520.3 +/- 20.2) mg/L to (608.9 +/- 20.2) mg/L, respectively (P < 0.05). Both IPS and EPS consisted of five kinds of components, and IPS-1 and EPS-1 were the major components of IPS and EPS, respectively. Further separation studies showed that IPS-1 was made up of three single compounds, while EPS-1 was made up of two single compounds. There were no new components in both IPS and EPS obtained from G lucidum in submerged culture by the addition of the insect, C. molossus, suggesting the biosynthetic pathways of the major components of IPS and EPS had not been changed.