Six Heterocyclic Metabolites from the Myxobacterium Labilithrix luteola
Lucky S. Mulwa,
Rolf Jansen,
Dimas F. Praditya,
Kathrin I. Mohr,
Joachim Wink,
Eike Steinmann,
Marc Stadler
Affiliations
Lucky S. Mulwa
Department of Microbial Drugs, Helmholtz Centre for Infection Research and German Centre for Infection Research (DZIF), partner site Hannover/Braunschweig, Inhoffenstrasse 7, 38124 Braunschweig, Germany
Rolf Jansen
Department of Microbial Drugs, Helmholtz Centre for Infection Research and German Centre for Infection Research (DZIF), partner site Hannover/Braunschweig, Inhoffenstrasse 7, 38124 Braunschweig, Germany
Dimas F. Praditya
TWINCORE—Centre for Experimental and Clinical Infection Research (Institute of Experimental Virology) Hanover. Feodor-Lynen-Str. 7–9, 30625 Hannover, Germany
Kathrin I. Mohr
Department of Microbial Drugs, Helmholtz Centre for Infection Research and German Centre for Infection Research (DZIF), partner site Hannover/Braunschweig, Inhoffenstrasse 7, 38124 Braunschweig, Germany
Joachim Wink
Work group Microbial Strain Collection (MISG), Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
Eike Steinmann
TWINCORE—Centre for Experimental and Clinical Infection Research (Institute of Experimental Virology) Hanover. Feodor-Lynen-Str. 7–9, 30625 Hannover, Germany
Marc Stadler
Department of Microbial Drugs, Helmholtz Centre for Infection Research and German Centre for Infection Research (DZIF), partner site Hannover/Braunschweig, Inhoffenstrasse 7, 38124 Braunschweig, Germany
Two new secondary metabolites, labindole A [2-methyl-3-(2-nitroethyl)-3H-indole] (1) and labindole B [2-methyl-3-(2-nitrovinyl)-3H-indole] (2), were isolated from the myxobacterium Labilithrix luteola (DSM 27648T). Additionally, four metabolites 3, 4, 5 and 6 already known from other sources were obtained. Their structures were elucidated from high resolution electrospray ionisation mass spectrometry (HRESIMS) and 1D and 2D nuclear magnetic resonance (NMR) spectroscopy data and their relative configuration was assigned based on nuclear Overhauser effect (NOE) and vicinal 1H-NMR coupling data. The compounds where tested for biological activities; labindoles A (1) and B (2) exhibited significant activity against Hepatitis C Virus, 9H-carbazole (3), 3-chloro-9H-carbazole (4) and 4-hydroxymethyl-quinoline (5) showed antifungal activities. Moreover, compound 3 had weak to moderate antibacterial activities, while labindoles A (1) and B (2) were devoid of significant antifungal and antibacterial effects.
