Functional Characterization of the Levopimaradiene Synthase in Escherichia coli and Differences in Functional Expression Patterns in Distinct Cell Lines

Levopimaradiene and dehydroabietane are two direct precursors of ginkgolides and exist only in the root tissue of Ginkgo biloba. To study the biosynthesis of ginkgolide, we chose undifferentiated G. biloba root tissue stem cells, which contain all the information needed for plant growth and development. Only dehydroabietane and abietadiene were determined by gas chromatography mass spectrometry in G. biloba root stem cell cultures. The results are consistent with the fermentation products of levopimaradiene synthase present in Escherichia coli under ultrasonic and bright light conditions. In addition, the products were also changed with changes in light and ultrasonic conditions and with just changes in light, indicating that levopimaradiene is converted to either dehydroabietane or abietadiene in the original plant in response to changes in external regulation and the plant's own needs.