Helmut Dittrich

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The berberine bridge enzyme [(S)-reticuline: oxygen oxidoreductase (methylene-bridge-forming), EC 1.5.3.9] is a vesicular plant enzyme that catalyzes the formation of the berberine bridgehead carbon of (S)-scoulerine from the N-methyl carbon of (S)-reticuline in a specific, unparalleled reaction along the biosynthetic pathway that leads to(More)
The pentacyclic biosynthetic precursor of jasmonic acid, 12-oxo-phytodienoic acid, was found to induce synthesis of the major flavonoid, apiin, in cell suspension cultures of Petroselinum crispum. The accumulation of apiin was preceded by an increase in the relative levels of poly (A)+ RNAs that code for the flavonoid biosynthetic enzymes phenylalanine(More)
The berberine bridge enzyme ((S)-reticuline:oxygen oxidoreductase (methylene-bridge-forming), EC 1.5.3.9) catalyzes the oxidative cyclization of the N-methyl moiety of (S)-reticuline into the berberine bridge carbon, C-8, of (S)-scoulerine. This is a reaction that has neither an equivalent in organic chemistry nor a parallel in nature. The uniqueness of(More)
The heterologous expression of cDNAs encoding the alkaloid biosynthetic enzymes, strictosidine synthase [EC 4.3.3.2] from Rauvolfia serpentina and the berberine bridge enzyme [(S)-reticuline: oxygen oxidoreductase (methylene-bridge-forming), EC 1.5.3.9] from Eschscholtzia californica, has been achieved in a cell culture (Sf9) of the fall army worm,(More)
Die Entwicklung zum modernen Ski ist charakteristisch für den Werkstoff Holz mit all seinen Stärken und Grenzen. Vom Eschenski ausgehend, versuchte man durch Sandwichkonstruktionen günstige Eigenschaften zu erzielen. Bald war die Grenze des reinen Holzskis erreicht; Kombinationen mit einer Vielzahl von Kunststoffen führten weiter. Tragende Elemente wurden(More)
The method of bacterial leaching of non precious dental alloys represents a useful completion of the method arsenal of biological investigations. In contrast to other well known methods it allows to point out small differences in corrosion resistance between alloys of the same type in a biologic system.