Search results for "Wolf"

Space-Efficient 1.5-Way Quantum Turing Machine

2001

1.5QTM is a sort of QTM (Quantum Turing Machine) where the head cannot move left (it can stay where it is and move right). For computations is used other - work tape. In this paper will be studied possibilities to economize work tape space more than the same deterministic Turing Machine can do (for some of the languages). As an example language (0i1i|i ≥ 0) is chosen, and is proved that this language could be recognized by deterministic Turing machine using log(i) cells on work tape , and 1.5QTM can recognize it using constant cells quantity.

Construction and expression of a dual vector for chemo-enzymatic synthesis of plant indole alkaloids inEscherichia coli

2010

A dual vector (pQE-70-STR1-SG) containing coding regions of strictosidine synthase (STR1, EC 4.3.3.2) and strictosidine glucosidase (SG, EC 3.2.1.105) from the Indian medicinal plant Rauvolfia serpentina was constructed. Functional expression of the vector in Escherichia coli cells (M15 strain) was proven by isolation of prepurified enzyme extracts, which show both STR1 and SG activities. Incubation of the enzyme in the presence of tryptamine and secologanin delivered the indole alkaloid cathenamine, demonstrating functional co-expression of both STR1- and SG-cDNAs. Cathenamine reduction by sodium borohydride leading to tetrahydroalstonine revealed the chemo-enzymatic indole alkaloid synthe…

A facile chemoenzymatic approach: one-step syntheses of monoterpenoid indole alkaloids.

2010

Facile chemoenzymatic syntheses of cytotoxic monoterpenoid indole alkaloids with novel skeletons and multiple chiral centers are described. Synthesis of these alkaloids was achieved by a simple one-step reaction using strictosidine and 12-aza-strictosidine as the key intermediates. Strictosidines were prepared by coupling of secologanin with tryptamine and 7-aza-tryptamine, respectively, using the immobilized recombinant Rauvolfia strictosidine synthase. A detailed stereochemical analysis is presented herein. The results provide an opportunity for a chemoenzymatic approach that leads to an increased diversification of complex alkaloids with improved structures and activities.

Vomilenine Reductase — a novel Enzyme catalyzing a crucial Step in the Biosynthesis of the Therapeutically applied Antiarrhythmic Alkaloid Ajmaline

2002

Delineation of the biochemical pathway leading to the antiarrhythmic Rauvolfia alkaloid ajmaline has been an important target in biosynthetic research for many years. The biosynthetic sequence starting with tryptamine and the monoterpene secologanin consists of about 10 different steps. Most of the participating enzymes have been detected and characterized previously, except those catalyzing the reduction of the intermediate vomilenine. A novel NADPH-dependent enzyme that reduces the intermediate has been isolated from Rauvolfia serpentina cell suspension cultures. Vomilenine reductase (M(r )43 kDa, temp opt 30 degrees C, pH opt 5.7-6.2), saturates the indolenine double bond of vomilenine w…

Crystallization and preliminary X-ray analysis of strictosidine synthase and its complex with the substrate tryptamine

2005

Strictosidine synthase (STR1) is a central enzyme that participates in the biosynthesis of almost all plant monoterpenoid indole alkaloids. After heterologous expression in Escherichia coli, crystals of STR1 and its substrate complex with tryptamine were obtained by the hanging-drop technique at 302–304 K with potassium sodium tartrate tetrahydrate as precipitant. All crystals belong to space group R3. The native STR1 crystals diffract to 2.95 Å and have unit-cell parameters a = b = 150.3, c = 122.4 Å. The tryptamine complex crystals diffract to 2.38 Å, with unit-cell parameters a = b = 147.3, c = 122.3 Å.

Piensa en compartir. Nuevos retos para diseñadores y empresas

2010

Tesis sobre el ecosocialismo como programa de liberación

2020

Bush y la extrema derecha

2003

F.A. Wolf, la scienza dell’antichità e noi: come possiamo uscire dal XIX secolo?

2011

International audience; Wolf’s historical-philological Altertumswissenschaft was an academic knowlegde helpful to the State because of its space and time limits, its methods and rhetoric, his idea of the Ancients as a mirror of modern ideals. The present crisis of this paradigm can be related to State’s decline and to modern globalisation, then to the development of fragmented research fields. This development isolated scholars from society and strengthened the problem of the meaning of studies. We can find a possible meaning of these studies for example: 1) by writing the history of the non-violent fights, 2) by trying the counterfactual history or the countertextual writing, examining the…

Kreikkalaisen tarun käytöstä

2019

Kirja-arvostelu teoksesta Wolf C. (2000). Medeia, Kertomus kuudella äänellä. (Saksankielinen alkuteos: Medea. Stimmen. 1996) Helsinki: Tammi Wolf C. (1985). Kassandra.(Saksankielinen alkuteos: Kassandra 1983) Helsinki: Kirjayhtymä. nonPeerReviewed