Enediyne core biosynthesis

Figure 3. Minimal PKSE cassettes for the C-1027 and NCS biosynthetic loci and a general paradigm for enediyne biosynthesis, (a) Organization of the enediyne gene cassettes found in the neocarzinostatin (NCS), and C-1027 loci, (b) Unified scheme for enediyne core biosynthesis carried out by the PKSE and associated accessory enzymes responsible for diverging common intermediate 5 into either 9- or 10-membered enediyne core pathways through the agency of carbacycles 6, 7 or 8. PKSE domain layout indicated is highly conservedfor all PKSEs characterized to date.

The biosynthesis of maduropeptin has not been studied in detail, but an iterative type I polyketide synthase gene predicted to be responsible for forming the enediyne core structure has been identified [188]. 

Figure 11.2 Biosynthesis of the nine-membered enediynes. Members of this family share a common biosynthetic pathway for the enediyne core intermediate. Domains are shown in circles with abbreviations (KS, ketosynthase AT, acyltransferase KR, ketoreductase DH, dehydratase TE, thioesterase ACP, acyl carrier protein PPT, phosphopantetheine transferase)...

Figure 3.90 Biosynthesis of the enediyne core and convergent strategy for assembling neocar zinostatin.

Subsequently, the organization of the 60-kb biosynthetic gene cluster of sporolides was reported. Putative assignments include spoE, E2-E11, and spoF in the biosynthesis of the enediyne core, spoTl-TlO in the construction and attachment of the cyclohexenone precursor, 6 genes involved in regulation, transport, and resistance, and 19 of unknown or unassigned function [472]. 

Figure 3.132 Proposed biosynthesis of the enediyne core, assembly, and cycloaromatization...

The biosynthesis of the enediyne core of calicheamicin and other similar compounds (both nine- and ten-membered) involve a common enediyne polyketide synthase (named PKSE) [295,... 

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