Cyaneodimycin, a Bioactive Compound Isolated from the Culture of Streptomyces cyaneofuscatus Associated with Lichina confinis

Abstract

Two new compounds, cyaneodimycin (1) and cyaneomycin (2) bearing a rare methacrylate residue, were isolated from cultures of the bacterium Streptomyces cyaneofuscatus associated with the marine lichen Lichina confinis. These astonishing structures may be derived from a pyruvate biosynthetic pathway. Cyaneodimycin (1) exhibited antiproliferative properties against B16 (IC 50 = 27 ± 4 μM), HaCaT (IC 50 = [a]

Lichen-associated bacteria transform antibacterial usnic acid to products of lower antibiotic activity

“…This strain was only sensitive to an exogenous addition of this antibiotic when this occurred before the beginning of biosynthesis. Furthermore, the effects of UA on bacterial growth were established at 0.1 mg/mL which is significantly higher than the level of UA production by S. cyaneofuscatus (0.04 µg/mL) (Parrot et al, 2016). As demonstrated by Goh et al, 2002, sub-inhibitory concentrations of antibiotics may have several beneficial effects on microorganisms, thus explaining the ecological benefits of this compound for the bacterial strain.…”

“…Growth and metabolism inhibition was also shown on S. cyaneofuscatus even though this strain is able to produce UA (Parrot et al, 2016). This was highlighted by the non-consumption of components of the culture medium and this time by a decrease in bacterial production.…”

“…Several compounds are not produced, probably due to growth inhibition. The production of the diketopiperazine cyclo-(L-Leu-L-Pro), a major compound eluting at 20.8 min (Parrot et al, 2016), is completely inhibited after UA treatment. Even after 7 days of stationary phase growth, these compounds are still not produced in the presence of UA.…”

“…Müll.) C. Agardh, was selected as a producer of UA (Parrot et al, 2016). The Firmicutes strain studied herein was isolated from the lichen Peltigera hymenina (Ach.)…”

Chemical analysis of the Alphaproteobacterium strain MOLA1416 associated with the marine lichen Lichina pygmaea

“…Those include angucycline and butenolide (Motohashi et al, 2010), coumabiocins A-F (Cheenpracha et al, 2010), cladoniamides A-G (Williams et al, 2008), uncialamycin (Davies et al, 2005) and the more recently described unciaphenol (Williams et al, 2015). Finally, we have recently isolated the two new acrylate compounds, cyaneodimycin and its derivative cyaneomycin, from isolates of Streptomyces cyaneofuscatus MOLA1488 isolated from Lichina confinis (Parrot et al, 2016b).…”