Establishment of Croton stellatopilosus Suspension Culture for Geranylgeraniol Production and Diterpenoid Biosynthesis

Abstract

Diterpenoids in higher plants are biosynthesized from isoprene units obtained from two distinct pathways: the mevalonate pathway and the deoxyxylulose phosphate pathway. The metabolic partitioning of both pathways in plant species is dependent upon the type of culture. In order to study the diterpenoid biosynthesis in Croton stellatopilosus cell culture, callus culture was firstly induced from C. stellatopilosus young leaves in Murashige and Skoog (MS) medium in the presence of 1.0 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D), 1.0 mg/l benzyladenine (BA), 3% (w/v) sucrose and 0.8% (w/v) agar. The suspension culture was further induced from its callus in the same medium without gelling agent. Detection of diterpenoid accumulation by gas chromatography-mass spectrometry revealed that a cell culture could accumulate a low amount of geranylgeraniol (GGOH) and a high content of fatty acids and phytosterols. To improve the GGOH production, the culture conditions were optimized by medium manipulation in terms of hormonal factors. The growth rates of cell cultures were similar in all kinds of media. The GGOH production curve indicated that GGOH plays an important role as a primary metabolite in the cell culture. The optimum medium for GGOH production was MS medium supplemented with 2.0 mg/l 2,4-D and 2 mg/l BA that could produce GGOH with a yield of 1.14 mg/g FW.

Biosynthesis of β-sitosterol and stigmasterol proceeds exclusively via the mevalonate pathway in cell suspension cultures of Croton stellatopilosus

“…The suspension culture was induced as described previously. 12 It was maintained in Murashige and Skoog (MS) medium 14 supplemented with 2 mg/L of 2,4-dichlorophenoxyacetic acid (2,4-D), 2 mg/L of benzyladenine (BA) and 3% w/v sucrose. Growth curves and product formation during the growth cycle of the suspension culture were first established.…”

Transcription Profiles Analysis of Genes Encoding 1-Deoxy-D-xylulose 5-Phosphate Synthase and 2C-Methyl-D-erythritol 4-Phosphate Synthase in Plaunotol Biosynthesis from Croton stellatopilosus

“…9) Earlier studies on the phytochemicals and their localization demonstrated that production of intermediates for terpenoid biosynthesis was related to chloroplastforming cells. 10,11) However for the early steps of isoprenoid biosynthesis in C. stellatopilosus, there is lack of knowledge about genes and enzymes, which have not as yet been reported. Therefore, the objective of this work is to study the genes encoding the 1-deoxy-D-xylulose 5-phosphate synthase (CSDXS) and 2C-methyl-D-erythritol 4-phosphate synthase (CSMEPS) from C. stellatopilosus.…”