Learn More
Level of expression of the hyp-1 gene encoding for the phenolic coupling protein which is assumed to be involved in conversion of emodin to hypericin in vitro was compared in different organs of Hypericum perforatum seedlings in early stage of development in order to find out the sites of hypericin biosynthesis. Hypericins are accumulated in multicellular(More)
Hairy root-regenerated clones of Hypericum perforatum L. grown in vitro similarly to those successfully adapted to ex vitro conditions showed phenotype features typical for plants transformed with Agrobacterium rhizogenes T-DNA. These included reduced apical dominance, increased branching, dwarfing and reduced fertility. Transgenic clones differed in(More)
The extent of phenotypic variation of St. John's wort (Hypericum perforatum L.) plants transformed with wild agropine ATCC 15834 Agrobacterium rhizogenes plasmid was evaluated with respect to the number of rol genes integrations. The transfer of T(L)-DNA to plant explants during each transformation event was incomplete with different rolA, rolB, and rolC(More)
Labelling of DNA in replicating cells using 5-bromo-2´-deoxyuridine (BrdU) is widely used, however the rapid clearance and metabolisation of BrdU in the living organism is a critical issue. Although the pharmacokinetic of BrdU in experimental animals is empirically approximated, the exact time-curve remains unknown. Here we present novel method for(More)
Extreme low temperatures cause plants multiple stresses, among which oxidative stress is presumed to be the major component affecting the resultant recovery rate. Plants of Hypericum perforatum L., which are known especially for the photodynamic activities of hypericins capable of producing reactive oxygen species under exposure to visible light, were(More)
The phenolic oxidative coupling protein (Hyp-1) with proposed activity in the biosynthesis of hypericin in Hypericum perforatum shares about 50 % sequence similarity with Bet.v.1-like/PR-10 proteins. In our previous study, we showed that this protein is not a limiting factor in hypericin biosynthesis. To ascertain the role of Hyp-1 in defense mechanisms, we(More)
The time-course of expression of dbat and dbtnbt genes involved in the later steps of paclitaxel biosynthesis and the intracellular taxane accumulation were investigated through a 64-day subculture interval of VI/M1 and VI/M2 Taxus baccata callus cultures. HPLC proved traces of baccatin III and an intracellular content of paclitaxel up to 90 microg/g DW.(More)
The content of hypericins in in vitro regenerated Hypericum perforatum plants (R 0) and four generations of their seed progeny (R 1–R 4) was compared. The mean content of hypericins in field-grown plants over the period 1992–2002 gradually increased under selection, and in the R 4 generation it was almost seven-times higher than that in the R 0 somaclones.(More)
Shoot-tips from in vitro cultured Hypericum perforatum L. genotypes were subjected to assessments of developmental competence, genetic stability, and biosynthetic ability to identify critical points during cryopreservation. Survival rate, chromosome number stability, alteration in VNTR sequences and hypericin content were evaluated, in plants after(More)
The possible microbial mechanism of hypericin (1) and emodin (2) biosynthesis was studied in axenic submerged culture conditions in the endophytic fungus Thielavia subthermophila, isolated from Hypericum perforatum. The growth and secondary metabolite production of the endophyte remained independent of the illumination conditions. This production remained(More)