Several phytochemicals were shown to interfere with redox biology in the human system. Moreover, redox biochemistry is crucially involved in the orchestration of immunological cascades. When screening for immunomodulatory compounds, the two interferon gamma- (IFN-γ-) dependent immunometabolic pathways of tryptophan breakdown via indoleamine 2,3-dioxygenase-1 (IDO-1) and neopterin formation by G...

Coffee beans of commercially important Coffea species contain the diterpene cafestol, which raises serum cholesterol in humans. Coffee diterpenes also have shown anticarcinogenic properties in experimental animals. We determined levels of cafestol and other diterpenes in nine wild African Coffea species, in a search for a species without the cholesterol-raising cafestol. In addition, data on di...

The diterpene ester PEP005 is a novel anticancer agent that activates protein kinase C (PKC) and induces cell death in melanoma at high doses. We now describe the in vitro cytostatic effects of PEP005 and the diterpene ester phorbol 12-myristate 13-acetate, observed in 20% of human melanoma cell lines. Primary cultures of normal human neonatal fibroblasts were resistant to growth arrest, indica...

The article shows the antioxidant properties of new derivatives 2-aminothiazole containing diterpene fragment. Using method luminol-dependent chemiluminescent analysis it is revealed that tested compounds under investigation exhibit in model test systems, where processes reactive oxygen species formation, lipid peroxidation, and cell phagocytosis blood are induced.

Secondary metabolites are major constituents of plant defense against herbivore attack. Relatively little is known about the cell type-specific formation and antiherbivore activities of secondary compounds in roots despite the substantial impact of root herbivory on plant performance and fitness. Here, we describe the constitutive formation of semivolatile diterpenes called rhizathalenes by the...

Cytochrome P450 monooxygenases (P450s) are important enzymes for generating some of the enormous structural diversity of plant terpenoid secondary metabolites. In conifers, P450s are involved in the formation of a suite of diterpene resin acids (DRAs). Despite their important role in constitutive and induced oleoresin defense, a P450 gene of DRA formation has not yet been identified. By using p...

Functional gene clusters, containing two or more genes encoding different enzymes for the same pathway, are sometimes observed in plant genomes, most often when the genes specify the synthesis of specialized defensive metabolites. Here, we show that a cluster of genes in tomato (Solanum lycopersicum; Solanaceae) contains genes for terpene synthases (TPSs) that specify the synthesis of monoterpe...

Abietadiene synthase catalyzes two sequential, mechanistically distinct cyclization reactions in the formation of a mixture of abietadiene double bond isomers as the committed step in resin acid biosynthesis. Each reaction is carried out at a separate active site residing in a structurally distinct domain, and the reactions are kinetically separable. The first cyclization reaction is initiated ...

The total synthesis of the diterpene kellermanoldione 1 is reported. Stepwise [4 + 2] cycloaddition of the ketal diene 8 and the allenoate 3 afforded the exo adduct 10x as the major product. It was converted into 1 via six steps, among them a key nonconjugative hydrolysis of a gamma-methylene silyl enol ether.