Biosynthesis

Erickson, W. R. ; Gould, S. J. "Streptonigrin Biosynthesis 8. Evidence for The Involvement of a New Shikimate Pathway Product and a New Route to Quinolines." J. Am. Chem. Soc. 1987, 109, 620.

Abstract:  Streptonigrin (I) exchanged oxygen with water exclusively at the C-8 carbonyl. [4-15N]4-aminoanthrilic acid and [4-2H]7-aminoquinoline-2-carboxylic acid were synthesized, and, when fed to fermns. of Streptomyces flocculus, were incorporated into I. Evidently, 4-aminoanthranilic acid is a new product of the shikimate pathway. This may be a fundamentally new route for the biol. formation of quinoline rings.

Erickson, W. R. ; Gould, S. J. "Streptonigrin Biosynthesis 7. Incorporation of Oxygen from 18O2: Evidence for an Oxidative ß-Carboline Cleavage." J. Am. Chem. Soc. 1985, 107, 5831.

Abstract:  Fermn. of Streptomyces flocculus in the presence of 18O2 resulted in the prodn. of streptonigrin (I) and the incorporation of 18O at 5 positions: at C-8', -9', and -10' of the Ph ring and at C-5 and -6 of the quinone ring. Thus, the oxygenation and cleavage of the β-carboline biosynthetic intermediate are all oxidative processes. Also, 4-amino-3-hydroxyanthranilic acid may be the precursor of the quinone ring.

Gerwick, B. C.; Fields, S.C.; Graupner, P. R.; Gray, J.; Chapin, E.; Cleveland, J.; Heim, D. "Pyridazocidin, a New Microbial Phytotoxin with Activity in the Mehler Reaction", Weed Science, 1997, 45, 654.

Abstract:  A new phytotoxin, pyridazocidin (I), was produced in shake-flask cultures of a Streptomyces sp. soil isolate. A combination of solvent partitioning, size-exclusion chromatog., and high-pressure liq. chromatog. (HPLC) was used to isolate the material. The structure was assigned based on mass spectroscopy and NMR (NMR) expts. Greenhouse evaluations indicated rapid necrosis and chlorosis of treated weeds, particularly of giant foxtail. Isolated chloroplasts consumed oxygen in the presence of pyridazocidin over a concn. range also inhibiting plant growth. Pyridazocidin represents the first re...

Schmitzer, Paul R.; Graupner, Paul R.; Chapin, Eleanor L.; Fields, Steven C.; Gilbert, Jeff R.; Gray, Jim A.; Peacock, Cathy L.; Gerwick, B. Clifford "Ribofuranosyl Triazolone: A Natural Product Herbicide with Activity on Adenylosuccinate Synthetase Following Phosphorylation", J. Nat. Prod. 2000, 63, 777.

Abstract:  2,4-Dihydro-4-(β-D-ribofuranosyl)-1,2,4(3H)-triazol-3-one (I) was identified as the principal phytotoxic component of a fermn. broth derived from an Actinomadura. I was also synthesized. Metabolite reversal studies suggested the target site was adenylosuccinate synthetase, which was confirmed by direct measurement of the activity of the 5'-phosphorylated deriv. on the isolated enzyme.

Erickson, W. R. "Studies On Advanced Intermediates In The Biosynthesis Of Streptonigrin"

Abstract:  Ph. D. Dissertation at Oregon State University, 1987.

Erickson, W. R. "Streptonigrin Biosynthesis 9. Isolation of 4 Aminoanthranilic Acid: A New Shikimate Pathway Product From Streptomyces flocculus." J. Antibiot. 1988, 41, 688.

Abstract:  Incubation of S. flocculus with erythrose results in a 0.22% incorporation into 4 aminoanthranilic acid, a natural product not previously observed in nature. Additional incubation yielded streptonigrin, whereas acetylation gave the bisacetamide.