Biosynthetic Precursors of Fungal Pyrrolizidines, the Loline Alkaloids

@article{Blankenship2005BiosyntheticPO,
  title={Biosynthetic Precursors of Fungal Pyrrolizidines, the Loline Alkaloids},
  author={J. D. Blankenship and J. B. Houseknecht and Sitaram Pal and L. Bush and R. B. Grossman and C. Schardl},
  journal={ChemBioChem},
  year={2005},
  volume={6}
}
Loline alkaloids are saturated pyrrolizidines with a substituted 1‐amino group and an oxygen bridge between C2 and C7, and are insecticidal metabolites of plant‐symbiotic fungi (endophytes). Cultures of the endophyte, Neotyphodium uncinatum, incorporated labeled L‐proline and L‐homoserine into the 1‐aminopyrrolizidine, N‐formylloline. The A‐ring carbons C1–C3 and the N1 were derived from L‐homoserine; the B‐ring carbons C5–C8 and the ring nitrogen were derived from L‐proline. Incorporation of… Expand
On the Sequence of Bond Formation in Loline Alkaloid Biosynthesis
TLDR
The sequence of bond formation in loline alkaloid biosynthesis was determined by synthesizing deuterated forms of potential intermediates and feeding them to cultures of the endophyte Neotyphodium uncinatum and it is suggested that N‐(3‐amino‐3‐carboxypropyl)proline is the first committed intermediate in l Caroline biosynthesis. Expand
Ether bridge formation in loline alkaloid biosynthesis.
TLDR
It is indicated that the non-heme iron oxygenase, LolO, is required for ether bridge formation, probably through oxidation of exo-1-acetamidopyrrolizidine. Expand
Ether Bridge Formation and Chemical Diversification in Loline Alkaloid Biosynthesis
TLDR
Results indicate that LolN is involved in deacetylating NANL to produce norloline, which is then modified to form the other lolines, supporting the hypothesis that LolM functions as a methyltransferase in the loline-alkaloid biosynthesis pathway. Expand
Enzymes from Fungal and Plant Origin Required for Chemical Diversification of Insecticidal Loline Alkaloids in Grass-Epichloë Symbiota
TLDR
The results indicated that lolN and lolM are required in the steps from N-acetylnorloline to other lolines, implying that deacetylation, methylation, and acetylation steps are all involved in loline alkaloid diversification. Expand
Review Loline alkaloids: Currencies of mutualism
TLDR
The history of loline discovery, methods of analysis, biological activities and distribution in nature, as well as progress on the genetics and biochemistry of their biosynthesis, and on the chemical synthesis of these alkaloids are discussed. Expand
Loline alkaloids: Currencies of mutualism.
TLDR
The history of loline discovery, methods of analysis, biological activities and distribution in nature, as well as progress on the genetics and biochemistry of their biosynthesis, and on the chemical synthesis of these alkaloids are discussed. Expand
Role of the LolP cytochrome P450 monooxygenase in loline alkaloid biosynthesis.
TLDR
Results and the inferred sequence of LolP1 indicate that it is a cytochrome P450, catalyzing oxygenation of an N-methyl group in NML to the N-formyl group in NFL. Expand
Pyrrolizidine alkaloids - chemistry, biosynthesis, pathway, toxicity, safety and perspectives of medicinal usage
S u m m a r y Pyrrolizidine alkaloids (PAs) are the class of secondary metabolites that evolved as a powerful tool in the plant defensive interactions against herbivores. The occurrence of PAs in theExpand
E/Z-Thesinine-O-4'-alpha-rhamnoside, pyrrolizidine conjugates produced by grasses (Poaceae).
TLDR
This is the first report of pyrrolizidine alkaloids produced by grasses (Poaceae) as a major component of perennial ryegrass (Lolium perenne) and tall fescue (Festuca arundinacea). Expand
Toxic Behaviour of Naturally Occurring Pyrrolizidine Alkaloids
TLDR
Chemistry, biosynthesis and metabolism of pyrrolizidine alkaloids have been summarized and PAs are reported for their hepatotoxicity, carcinogenicity and genotoxity. Expand
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