Biosynthetic anatoxin

Fig. 6.4 Biosynthetic subunits to anatoxin-a from feeding various labeled substrates [13],...

The first studies on the biosynthesis of these neurotoxin involved feeding experiments using labeled precursors, which, although allowed the researchers to establish that anatoxin-a results from the condensation of three acetate units on (5)-l-pyrroline-5-carboxylate (P5C) that is derived from glutamate followed by a decarboxylation and that homoanatoxin-a would result from methylation of anatoxin-a, could not lead to the elucidation of the individual chemical steps of the biosynthetic pathway [77]. 

Figure 5.19 Proposed biosynthetic pathway to anatoxin-a and homoanatoxin-a starting from proline. KS, ketosynthase AT, acyltransferase KR, ketoreductase DH, dehydrogenase ER, enoylreductase ACP, acyl carrier protein Cy, cyclase and CM, methyllransferase.

Fig. 3.3 Biosynthesis of anatoxin-a and homoanatoxin-a in cyanobacteria genes and biosynthetic pathway...

Selwood AI, Holland PT, Wood SA, Smith KF, McNabb PS (2007) Production of anatoxin-a and a novel biosynthetic precursor by the cyanobacterium Aphanizomenon issatschenkoi. Environ Sci Technol 41 506-510. doi 10.1021/es061983o... 

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