18 research outputs found
Alkaloid production by a Cinchona officinalis "Ledgeriana" hairy root culture containing constitutive expression constructs of tryptophan decarboxylase and strictosidine synthase cDNAs from Catharanthus roseus
Cinchona officinalis âLedgerianaâ, former
called Cinchona ledgeriana, hairy roots were initiated
containing constitutive-expression constructs of cDNAs
encoding the enzymes tryptophan decarboxylase
(TDC) and strictosidine synthase (STR) from Catharanthus roseus, two key enzymes in terpenoid indole
and quinoline alkaloid biosynthesis. The successful
integration of these genes and the reporter gene gus-int
was demonstrated using Southern blotting and the
polymerase chain reaction. The products of TDC and
STR, tryptamine and strictosidine, were found in high
amounts, 1200 and 1950 mg gâ1 dry weight, respectively.
Quinine and quinidine levels were found to rise up to
500 and 1000 mg gâ1 dry weight, respectively. The
results show that genetic engineering with multiple
genes is well possible in hairy roots of C. officinalis.
However, 1 year after analyzing the hairy roots for the
first time, they had completely lost their capacity to
accumulate alkaloids.info:eu-repo/semantics/publishedVersio
Alkaloid production by a Cinchona officinalis "Ledgeriana" hairy root culture containing constitutive expression constructs of tryptophan decarboxylase and strictosidine synthase cDNAs from Catharanthus roseus
Cinchona officinalis âLedgerianaâ, former
called Cinchona ledgeriana, hairy roots were initiated
containing constitutive-expression constructs of cDNAs
encoding the enzymes tryptophan decarboxylase
(TDC) and strictosidine synthase (STR) from Catharanthus roseus, two key enzymes in terpenoid indole
and quinoline alkaloid biosynthesis. The successful
integration of these genes and the reporter gene gus-int
was demonstrated using Southern blotting and the
polymerase chain reaction. The products of TDC and
STR, tryptamine and strictosidine, were found in high
amounts, 1200 and 1950 mg gâ1 dry weight, respectively.
Quinine and quinidine levels were found to rise up to
500 and 1000 mg gâ1 dry weight, respectively. The
results show that genetic engineering with multiple
genes is well possible in hairy roots of C. officinalis.
However, 1 year after analyzing the hairy roots for the
first time, they had completely lost their capacity to
accumulate alkaloids.info:eu-repo/semantics/publishedVersio
Suspension cultured transgenic cells of Nicotiana tabacum expressing tryptophan decarboxylase and strictosidine synthase cDNAs from Catharanthus roseus produce strictosidine upon secologanin feeding
A transgenic cell suspension culture of Nicotiana tabacum L. âPetit Havanaâ SR1 was established expressing tryptophan decarboxylase and strictosidine synthase cDNA clones from Catharanthus roseus (L.) G. Don
under the direction of cauliflower mosaic virus 35S promoter and nopaline synthase terminator sequences. During a growth cycle, the transgenic tobacco cells showed
relatively constant tryptophan decarboxylase activity and
an about two- to sixfold higher strictosidine synthase activity, enzyme activities not detectable in untransformed
tobacco cells. The transgenic culture accumulated tryptamine and produced strictosidine upon feeding of secologanin, demonstrating the in vivo functionality of the two
transgene-encoded enzymes. The accumulation of strictosidine, which occurred predominantly in the medium, could
be enhanced by feeding both secologanin and tryptamine.
No strictosidine synthase activity was detected in the medium, indicating the involvement of secologanin uptake
and strictosidine release by the cells.info:eu-repo/semantics/publishedVersio
Suspension cultured transgenic cells of Nicotiana tabacum expressing tryptophan decarboxylase and strictosidine synthase cDNAs from Catharanthus roseus produce strictosidine upon secologanin feeding
A transgenic cell suspension culture of Nicotiana tabacum L. âPetit Havanaâ SR1 was established expressing tryptophan decarboxylase and strictosidine synthase cDNA clones from Catharanthus roseus (L.) G. Don
under the direction of cauliflower mosaic virus 35S promoter and nopaline synthase terminator sequences. During a growth cycle, the transgenic tobacco cells showed
relatively constant tryptophan decarboxylase activity and
an about two- to sixfold higher strictosidine synthase activity, enzyme activities not detectable in untransformed
tobacco cells. The transgenic culture accumulated tryptamine and produced strictosidine upon feeding of secologanin, demonstrating the in vivo functionality of the two
transgene-encoded enzymes. The accumulation of strictosidine, which occurred predominantly in the medium, could
be enhanced by feeding both secologanin and tryptamine.
No strictosidine synthase activity was detected in the medium, indicating the involvement of secologanin uptake
and strictosidine release by the cells.info:eu-repo/semantics/publishedVersio
Side loads measurements on subscale launcher nozzles
Communication to : 4th international conference on space launcher liquid, Liege (Belgique), December 03-06, 2002Available from INIST (FR), Document Supply Service, under shelf-number : 22419, issue : a.2003 n.70 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc