RESUMO
By employing a novel technique for the direct coupling of a bacterial bioassay with chromatography, we discovered a gyrA promotor active compound in myxobacterial extracts and elucidated the structure directly without any isolation step. As a result, we identified inthomycin A as the bioactive substance. Our method is based on a whole-cell bioluminescent reporter gene assay coupled with thin-layer chromatography for primary hit detection and with liquid chromatography (LC)/mass spectrometry or LC/NMR for dereplication and structure elucidation. Previously, inthomycin A has been isolated from Streptomycetes and was associated with the inhibition of cellulose biosynthesis and herbicidal activity. Thus, our findings support the basic principle that completely different microbial phyla are able to synthesize the same natural product. Moreover, our results indicate that inthomycin A affects bacterial DNA supercoiling, which reveals an unexpected bioactivity for this compound. These results can possibly promote further investigation of the biosynthesis as well as the biological activity of inthomycins and related natural products.
Assuntos
Antibacterianos/farmacologia , DNA Super-Helicoidal/efeitos dos fármacos , Luminescência , Myxococcales/química , Antibacterianos/química , Cromatografia em Camada Fina/métodos , Espectroscopia de Ressonância Magnética/métodosRESUMO
Our search for a new broad spectrum bactericide for preserving materials lead to the discovery of a highly active bicyclic amine (1) and a number of derivatives. The synthesis and biological evaluation as well as a first toxicological assessment of these compounds are described. Compound 1 shows strong bactericidal activity down to levels of below 100 ppm but unfortunately increases the number of mutations in Ames tests.