Search results for "Biosynthesi"

Alkaloids from Rauwolfia serpentina cell cultures treated with ajmaline

1993

Abstract A group of new alkaloids, the raumaclines, and some related alkaloids were isolated from Rauwolfia serpentina cell suspensions fed with high levels of ajmaline; their structures were determined and syntheses developed providing an essential prerequisite to the further study of their biosynthesis at the enzymatic level.

Carnitine transport in volume-overloaded rat hearts

1995

Carnitine concentration in tissue is generally related to mitochondrial volume-density and ability to oxidize fatty acids. The highest tissue carnitine has been detected in ventricular myocardium which, compared to other tissues, presents elevated rates of oxidative phosphorylation [1]. The ability of cardiac mitochondria to oxidize long chain fatty acids is also much higher when compared to skeletal muscle or liver sarcosomes (Table 1). Paradoxically enough, it has been known for many years [3–5] that the heart is missing γ-butyrobetaine hydroxylase [6, 7], the last enzyme of carnitine synthesizing pathway, and that in the myocardium of different species including man, the carnitine synthe…

Biosynthesis of Monoterpenoid Indole Alkaloid Ajmaline Catalyzed by Novel Reductases1

2006

Iron ions as the modulators of biosynthesis of cyanobacterial dyes

2016

Chapter 2 Biosynthesis in Rauwolfia serpentina Modern Aspects of an Old Medicinal Plant

1995

Publisher Summary This chapter discusses a research on Rauwolfia , which was achieved after the generation of a cell suspension with extraordinary growth characteristics and physiological behavior. The investigations demonstrated that a range of techniques is now available for the clarification of complete metabolic pathways, provided that the appropriate efficient biological system is available. The isolation and identification of each single enzyme have almost become routine, even if an extremely sensitive protein analytic technique is necessary when several kilograms of fresh plant cells are reduced to a few micrograms of homogenous protein. The successful identification of a total of 20…

Über die mikrobiologische Umwandlung N-haltiger Substrate. 3. Mitt.: Über die Konstitutionsaufklärung von Umwandlungsprodukten des 5-Hydroxyindols du…

1968

In Schuttelkulturen von Cordyceps militaris entstehen aus 5-Hydroxyindol zwei neue Substanzen, die nach Chromatographie an Polyamidsaulen und nachfolgender Isolierung auf Grund ihres chemischen Verhaltens gegenuber Diazomethan sowie ihrer Elementaranalysen, IR-, Massen-und NMR-Spektren als ω-N-Acetyl-5-hydroxy-tryptophan und ω-N-Acetyl-serotonin identifiziert wurden. Two new substances are produced in submerged cultures of Cordyceps militaris fed with 5-hydroxyindole. These substances, separated by column chromatography with polyamide and isolated afterwards, have been identified as ω-N-acetyl-5-hydroxytryptophan and ω-N-acetyl-serotonin by their reaction with diazomethane, by elementary an…

Analysis of Invariant Chain Processing in 3 Day Cultured Rat Langerhans Cells

1995

MHC class II molecules, critical peptide binding elements involved in the presentation of exogenous antigen to T helper cells, are expressed constitutively by Langerhans cells (LC) within their epidermal microenvironment. Several studies in mouse and man demonstrated, that short term in vitro culture of LC entails remarkable functional and penotypic alterations, including a profound increase of class II elements exposed at the LC’s surface1. Biosynthetic analysis revealed a downregulation of class II synthesis during the culture period2,3. In recent work on rat LC we described the uncoupling of the coordinately regulated biosynthesis of class II and invariant chain proteins in the course of…

Five-Membered Heterocyclic Rings and Their Fused Derivatives

2015

In vitro biosynthesis of beauvericin and enniatins by Fusarium avenaceum and Fusarium poae strains isolated from Italian durum wheat grains

2015

Alkylation of RNA by Vinyl Chloride and Vinyl Bromide Metabolites in Vivo: Effect on Protein Biosynthesis

1981

Alkylation of DNA is viewed as representing the initial critical step in carcinogenesis induced by chemical substances. Vinyl chloride and vinyl bromide, compounds with proven carcinogenic potency toward the liver, are biotransformed to reactive metabolites which covalently bind to DNA (see Bolt et al. 1980). Furthermore, extensive covalent binding of metabolites of both vinyl chloride (Laib and Bolt 1977, 1978) and vinyl bromide (Ottenwalder et al. 1979) occurs to RNA of liver when rats are exposed to both vinyl halides. Defined products of alkylation are 1,N6-ethenoadenosine (Laib and Bolt 1777; Ottenwalder et al. 1979) and 3,N4-ethenocytidine (Laib and Bolt 1978; Ottenwalder et al. 1979)…