ABSTRACT
The chemical constituents of Taxus chinensis var. mairei cell cultures were investigated by chromatographic methods, including silica gel column chromatography, Sephadex LH-20 and preparative HPLC. Thirteen compounds were isolated from the 80% ethanol extract of cultured cells and their structures were elucidated by spectral data and physicochemical properties, which were identified as 2α,4α,7β,9α,10β-pentaacetoxy-14β-hydroxytax-11-ene (1), 2α,4α,7β,9α,10β-pentaacetoxytax-11-ene (2), 1β-deoxybaccatin VI (3), 2α-acetoxytaxusin (4), taxuyunnanine C (5), yunnanxane (6), 2α,5α,10β-triacetoxy-14β-propionyloxy-4 (20), 11-taxadiene (7), 2α,5α,10β-triacetoxy-14β-isobutyryloxy-4 (20), 11-taxadiene (8), 2α,5α,10β-triacetoxy-14β-(2'-methyl)butyryloxy-4 (20), 11-taxadiene (9), 13-dehydroxylbaccatin III (10), 13-dehydroxy-10-deacetylbaccatin III (11), paclitaxel (12) and (13) β-sitosterol. Among them, compound 1 is a new compound, and compounds 2, 4, 10 and 11 are isolated from the cell culture of Taxus chinensis var. mairei for the first time.
Subject(s)
Alkenes , Cell Culture Techniques , Cells, Cultured , Diterpenes , Molecular Structure , Paclitaxel , Sitosterols , Taxoids , Taxus , ChemistryABSTRACT
Two strategies, direct ligation after enzyme digestion and over-lap PCR technology, were adopted to construct a fusion gene which was composed of the antimelanoma single chain antibody gene and the staphylococcal enterotoxin A gene without N-terminal signal sequence. The fusion gene was subcloned into pET28-a vector and transformed into E. coli BL21(DE3). Ni-NTA system was selected to separate and purify the expresstd products. The inhibition ratio of the fusion protein was tested by MTT method. It is shown that the 6His-ScFv-SEA fusion protein can be expressed stably in E. coli BL21 (DE3). The quantity of the fusion protein was shown up to 30% of the total protein of the bacteria and mainly in inclusion body. By activation the effective cells, the fution protein can inhibit the melanoma cell whith expressed corresponding antigen.