Title: Biosynthesis of 4-aminoheptose 2-epimers, core structural components of the septacidins and spicamycins Authors
|Furukawa, Takayuki -|
|Cheng, Fang -|
|Qi, Jianzhao -|
|Chen, Wenqing -|
|Crich, David -|
Submitted to: Journal of the American Chemical Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 27, 2014
Publication Date: February 25, 2014
Citation: Price, N.P., Furukawa, T., Cheng, F., Qi, J., Chen, W., Crich, D. 2014. Biosynthesis of 4-aminoheptose 2-epimers, core structural components of the septacidins and spicamycins. Journal of the American Chemical Society. 67(5):405-414. Interpretive Summary: Septacidins and spicamycins are antifungal agents produced by fermentation of Streptomyces soil bacteria and as such, may have potential value in fighting crop disease. In this research, we obtained formal evidence that although these two compounds are very similar they differ in their stereochemistry at just one carbon atom. These results suggest that the biosynthesis of the septacidins differs from that of the related spicamycins, which may ultimately allow novel compounds to be produced with alternative biological properties. This work on the production of septacidins by a soil bacterium may ultimately be beneficial for treatment of important fungal diseases of crops or agricultural animals.
Technical Abstract: Septacidins and spicamycins are acylated 4-aminoheptosyl-ß-N-glycosides produced by Streptomyces fimbriatus and S. alanosinicus, respectively. Their structures are highly conserved, but differ in the stereochemistry of the 4-aminoheptosyl residues. The origin of this stereochemistry is unknown, but is presumably due to difference in their biosynthetic pathways. We have synthesized the septacidin 4-aminoheptose to verify the difference between septacidin and spicamycin. Isotopic enrichment studies were undertaken using S. fimbriatus, and show that the septacidin heptose is derived from the pentose phosphate pathway. This indicates conserved pathways leading to the biosynthesis of 4-amino-4-deoxy-L-glucoheptanose or 4-amino-4-deoxy-L-mannoheptanose.