Search results for "wolf"

Acetyltransfer in natural product biosynthesis--functional cloning and molecular analysis of vinorine synthase.

2004

Vinorine synthase (EC 2.3.1.160) catalyses the acetyl-CoA- or CoA-dependent reversible formation of the alkaloids vinorine (or 11-methoxy-vinorine) and 16-epi-vellosimine (or gardneral). The forward reaction leads to vinorine, which is a direct biosynthetic precursor along the complex pathway to the monoterpenoid indole alkaloid ajmaline, an antiarrhythmic drug from the Indian medicinal plant Rauvolfia serpentina. Based on partial peptide sequences a cDNA clone was isolated and functionally expressed in Escherichia coli. The Km values of the native enzyme for gardneral and acetyl-CoA were determined to be 7.5 and 57 microM. The amino acid sequence of vinorine synthase has highest level of i…

Deoxysarpagine Hydroxylase — A Novel Enzyme Closing a Short Side Pathway of Alkaloid Biosynthesis in Rauvolfia

2002

Microsomal preparations from cell suspension cultures of the Indian plant Rauvolfia serpentina catalyze the hydroxylation of deoxysarpagine under formation of sarpagine. The newly discovered enzyme is dependent on NADPH and oxygen. It can be inhibited by typical cytochrome P450 inhibitors such as cytochrome c, ketoconazole, metyrapone, tetcyclacis and carbon monoxide. The CO-effect is reversible with light (450 nm). The data indicate that deoxysarpagine hydroxylase is a novel cytochrome P450-dependent monooxygenase. A pH optimum of 8.0 and a temperature optimum of 35 degrees C were determined. K(m) values were 25 microM for NADPH and 7.4 microM for deoxysarpagine. Deoxysarpagine hydroxylase…

Volfgangs Goethe: dzīve un darbi [Volfgangs Gēte]

1925

Saturs: Ievadam 5 Goethes bērnība un agrā jaunība 13 Studenta gadi 26 Herders 36 Vētras un trauksmes laikmets 41 Egmonts un uzvara par jaunības titānismu 58 Pirmie gadi Veimārā 67 Itālijā 82 Atkal Veimārā 94 Ifigenija un Tasso 99 Šillers 113 Goethes audzināšanas romāns — Vilhelms Meisters 118 Goethes paša sevis audzināšana 146 Goethe un politika 154 Hermans un Doroteja 168 Pēc Šillera nāves 172 Pirmradniecība 185 Goethes Pandora un viņa atmiņu grāmata 192 Goethes lirikas posmi 206 Goethe kā domātājs 233 Goethes dzīves gudrība 260 Fausts 289 Goethes rakstu izdevumi 334 Literatūra par Goethi 334

Electronic properties and high-pressure behavior of wolframite-type CoWO4

2021

In this work we characterize wolframite-type CoWO4 under ambient conditions and under compression up to 10 GPa, with emphasis on its electronic structure. X-Ray diffraction and vibrational experiments, supported by ab initio calculations, show that CoWO4 is stable under high-pressure conditions, as no structural changes are detected in the studied pressure range. Interesting findings come from optical absorption spectroscopy. On the one hand, CoWO4 is confirmed to have one of the lowest band gaps among similar wolframites, around 2.25 eV. This makes CoWO4 suitable for use in applications such as the photocatalysis of organic pollutants and water splitting. Additionally, a monotonic decrease…

Sexual signalling and viability in a wolf spider ( Hygrolycosa rubrofasciata ): measurements under laboratory and field conditions

1999

This study examined the crucial prediction of the conditional-handicap theory, the relationship between male sexual trait size and male viability, in the wolf spider Hygrolycosa rubrofasciata. In this species, males court females by drumming dry leaves with their abdomen, and males with the highest drumming rate enjoy highest mating success. We determined male drumming rate, body mass, and mobility, which reflects mate-searching activity, in relation to male survival. Because it is often difficult to know how results obtained from laboratory studies reflect the natural world, particularly when the measured variable is survival, we repeated our study in both laboratory and field conditions. …

Analysis of Rauwolfia Alkaloids Employing Capillary Electrophoresis-Mass Spectrometry

1997

Abstract Capillary electrophoresis-mass spectrometry (CE-MS) was applied to analyse extracts of roots and cell suspension cultures from Rauwolfia serpentina. Most of the alkaloids known to be present in the respective plant material have been resolved via CE and assigned according to their electrospray mass spectra.

Nitric oxide radicals are emitted by wasp eggs to kill mold fungi

2019

Detrimental microbes caused the evolution of a great diversity of antimicrobial defenses in plants and animals. Insects developing underground seem particularly threatened. Here we show that the eggs of a solitary digger wasp, the European beewolf Philanthus triangulum, emit large amounts of gaseous nitric oxide (NO⋅) to protect themselves and their provisions, paralyzed honeybees, against mold fungi. We provide evidence that a NO-synthase (NOS) is involved in the generation of the extraordinary concentrations of nitrogen radicals in brood cells (~1500 ppm NO⋅ and its oxidation product NO2⋅). Sequencing of the beewolf NOS gene revealed no conspicuous differences to related species. However,…

Las armas de falsedad masiva (I)

2004

La guerrilla atlántica

2004

Viability costs of condition-dependent sexual male display in a drumming wolf spider

1996

According to the conditional handicap models females use male ornaments as honest signals of male viability. The assumptions for honest signalling are that the traits are costly and that they reflect male phenotypic condition, and hence optimal trait size is largest in the most viable males. However, experimental evidence for the costs of signalling are scarce. In this study we experimentally tested whether acoustic signalling, drumming, in a wolf spider Hygrolycosa rubrofasciata is a condition dependent, costly trait, and thus offers an honest signal of quality to females. Males of this species court females by drumming dry leaves with their abdomen. Females prefer to mate with males of hi…