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The manuscript investigated the isolation, characterization and anti-infective potential of valinomycin (<b>3</b>), streptodepsipeptide P11A (<b>2</b>), streptodepsipeptide P11B (<b>1</b>), and one novel valinomycin analogue, streptodepsipeptide SV21 (<b>4</b>), which were all produced by the Gram-positive strain <i>Streptomyces</i><i>cavourensis</i> SV 21. Although the exact molecular weight and major molecular fragments were recently reported for compound <b>4</b>, its structure elucidation was not based on compound isolation and spectroscopic techniques. We successfully isolated and elucidated the structure based on the MS² fragmentation pathways as well as ¹H and ¹³C NMR spectra and found that the previously reported structure of compound <b>4</b> differs from our analysis. Our findings showed the importance of isolation and structure elucidation of bacterial compounds in the era of fast omics technologies. The here performed anti-infective assays showed moderate to potent activity against fungi, multi drug resistant (MDR) bacteria and infectivity of the Hepatitis C Virus (HCV). While compounds <b>2</b>, <b>3</b> and <b>4</b> revealed potent antiviral activity, the observed minor cytotoxicity needs further investigation. Furthermore, the here performed anti-infective assays disclosed that the symmetry of the valinomycin molecule is most important for its bioactivity, a fact that has not been reported so far.