Nicotiana silvestris

Solubilization of Membrane Proteins. A modification of the procedure of Hjelmeland et al. (30) was employed. A 300-g portion of liquid-nitrogen frozen, 6-day Nicotiana silvestris cultured cells was suspended in 200 ml of 50 mM N-(2-hydroxyethyl)-piperazine-N -3-propanesulfonic acid (EPPS-KOH) buffer, 1 mM dithiothreitol (DTT), and 0.1 mM EDTA extraction buffer with constant stirring until completely suspended (20 min). The slurry was centrifuged in a Sorvall SS 34 rotor at 9,000g for 20 min at 4°C. The supernatant was passed through miracloth (Calbiochem). An aliquot... 

Topping and pruning increase not only the relative but also the absolute amount of alkaloids in these species (244, 319-324) and bleeding sap analyses readily confirm this observation (265, 283). Photoperiodic prevention of flowering will also maintain the alkaloid synthetic activity of Nicotiana silvestris Speg. and Comes (Table 2). These findings are contradictory in part to earlier ones (324, 325), but the discrepancy is probably due to the fact that the earlier w ork paid inadequate attention to absolute rather than to relative amounts of alkaloids. 

Most of our studies have been carried out in Nicotiana silvestris, chosen for the following advantageous characteristics. It is a true diploid (2n=24). A background of basic classical genetics exists. It is self-fertile, flowers rapidly and produces numerous seeds. It has a relatively short life cycle. Haploids are readily obtained. It grows rapidly in suspension culture and is totipotent. Protoplast techniques have been developed and somatic-cell hybridization is feasible. 

L-Tyrosine regulation and biosynthesis via arogenate dehydrogenase in suspension-cultured cells of Nicotiana silvestris (Speg. et Comes). Planta 156 233-240. 

Subcellular localization of chorismate-mutase isoenz3nnes in protoplasts from mesophyll and suspension-cultured cells of Nicotiana silvestris. Planta 162 104-108. 

Escherichia coli Escherichia coli Escherichia coli Klebsiella pneumoniae Klebsiella pneumoniae Neurospora crassa Candida maltosa Corydalis sempervirens Corydalis sempervirens Nicotiana silvestris Petunia hybrida Pisum sativum... 

Glyphosate inhibition of 5-enolpyruvylshikimate 3-phosphate synthase from suspension-cultured cells of Nicotiana silvestris. Plant Physiol. 75 829-845. 

Z)-Abienol 28 isolated from Canada fir balsam is a predominant labdane of some fresh tobacco leaf varieties and some of its oxidation products are responsible for specific smoke aromas. In order to identify and produce some of these oxidized metabolites, (Z)-abienol metabolites created by soil microorganisms were investigated a Nocardia restricta strain (ITS 162) [31,32] and a Rhodococcus erythropolis strain (ITS 131) [16] produced hydroxymethyl and carboxylic acid derivatives at C-17 and C-18, respectively, which accumulated in the presence of metabolic inhibitors such as a,a-dipyridyl. A recent study using plant cell cultures of Nicotiana silvestris, or simple incubations of (Z)-abienol with horseradish peroxidase, demonstrated the formation of 12 identified degradation metabo-htes [33]. 

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