Spatial heterogeneity in the strength or agents of selection can lead to geographic variation in ecologically important phenotypes. Many dendrobatid frogs sequester alkaloid toxins from their diets and often exhibit fixed mutations at NaV1.4, a voltage-gated sodium ion channel associated with alkaloid toxin resistance. Yet previous studies have noted an absence of resistance mutations in indivi...

Males of the moth Cosmosoma myrodora (Arctiidae) acquire pyrrolizidine alkaloid by feeding on the excrescent fluids of certain plants (for instance, Eupatorium capillifolium). They incorporate the alkaloid systemically and as a result are protected against spiders. The males have a pair of abdominal pouches, densely packed with fine cuticular filaments, which in alkaloid-fed males are alkaloid ...

BACKGROUND AND AIMS Previous measurements of conifer alkaloids have revealed significant variation attributable to many sources, environmental and genetic. The present study takes a complementary and intensive, common garden approach to examine genetic variation in Pinus ponderosa var. ponderosa alkaloid production. Additionally, this study investigates the potential trade-off between seedling ...

Transcription factors of the basic Helix-Loop-Helix (bHLH) family play a central role in cell proliferation, determination, and differentiation. In plants, the regulatory functions of bHLHs in phenylpropanoid biosynthesis have been well established with regard to other interacting-proteins; i.e., MYB and WD40 repeat proteins. On the other hand, those in alkaloid biosynthesis are greatly limited...

background and objectives: many members of the amaryllidaceae are regarded as toxic. the toxic constituents that occur in the whole family are referred to as the amaryllidaceae alkaloids. the main aim of this study was the identification of alkaloid compounds from galanthus transcaucasicus fomin, a medicinal plant from amaryllidaceae. methods: planar and column chromatography techniques were us...

the solanaceae plants produce a variety of interesting biologically active products including the steroid alkaloids solanidine, nicotine and tropane alkaloids. putrescine n-methyltransferase (pmt) is an enzyme that catalyses s-adenosylmethionine-dependent methylation of putrescine in one of the primary steps of nicotine and tropane alkaloids biosynthesis pathway. two tobacco members of the ap2/...

Addition of biotin to culture medium NL-406 significantly increased alkaloid yield during submerged cultivation of Claviceps sp. strain SD-58. Alkaloid yield was further enhanced by incorporating leucine in biotin-supplemented culture medium. Increased alkaloid production was associated with an increase in the lipid content of cells and in the number of chlamydospores. Biotin deficiency caused ...

Stachydrine (I), the methyl betaine of proline, occurs in a number of plants (1). Its biogenesis has been the subject of an investigation by Klein and Linser (2) who found an increase in stachydrine content of the planbs after an injection of proline into the hollow stems of Guleopsis ochroleuca and Stachys palustris. They suggest two schemes for the biogenesis of proline, one from ornithine, t...