Biosynthetic Pathway of Fluoroacetate in Streptomyces cattleya

Abstract

The biosynthetic pathway of fluoroacetate in Streptomyces cattleya NRRL 8057 was studied by ¹⁹F-NMR and tracer experiments with various ¹⁴C-labeled compounds. Radioactivity of ¹⁴C-labeled glucose, glycerol, pyruvate, L-serine, β-hydroxypyruvate, succinate and L-aspartate was incorporated into fluoroacetate during incubation of them with growing and resting cells of S. Cattleya NTG29, a mutant strain overproducing fluoroacetate. Comparison of the ratio of radioactivity incorporated into fluoroacetate from the above compounds to that administered revealed the major biosynthetic pathway of fluoroacetate through β-hydroxypyruvate. Its C₂ and C₃ carbons were efficiently incorporated into fluoroacetate, but no significant incorporation of its C₁ carbon was found. Thus, β-hydroxypyruvate is probably fluorinated by replacement of the hydroxyl group by fluoride anion and then decarboxylated to form fluoroacetate.