AUTHOR=Wang Dongyang , Wang Cong , Gui Pengyan , Liu Haishan , Khalaf Sameh M. H. , Elsayed Elsayed A. , Wadaan Mohammed A. M. , Hozzein Wael N. , Zhu Weiming 

TITLE=Identification, Bioactivity, and Productivity of Actinomycins from the Marine-Derived Streptomyces heliomycini

JOURNAL=Frontiers in Microbiology

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2017.01147

DOI=10.3389/fmicb.2017.01147

ISSN=1664-302X

ABSTRACT=<p>In the process of profiling the secondary metabolites of actinobacteria isolated from the Saudi coastal habitats for production of antibiotics and anti-cancer drugs, the cultures of strain WH1 that was identified as <italic>Streptomyces heliomycini</italic> exhibited strong antibacterial activity against <italic>Staphylococcus aureus</italic>. By means of MS and NMR techniques, the active compounds were characterized as actinomycins X<sub>0β</sub>, X<sub>2</sub>, and D, respectively. The research on the productivity of this strain for actinomycins revealed that the highest production of actinomycins X<sub>0β</sub>, X<sub>2</sub>, and D was reached in the medium MII within 5% salinity and pH 8.5. In this optimized condition, the fermentation titers of actinomycins X<sub>0β</sub>, X<sub>2</sub>, and D were 107.6 ± 4.2, 283.4 ± 75.3, and 458.0 ± 76.3 mg/L, respectively. All the three actinomycins X<sub>0β</sub>, X<sub>2</sub>, and D showed potent cytotoxicities against the MCF-7, K562, and A549 tumor cell lines, in which actinomycin X<sub>2</sub> was the most active against the three tumor cell lines with the IC<sub>50</sub> values of 0.8–1.8 nM. Both actinomycins X<sub>2</sub> and D showed potent antibacterial activities against <italic>S. aureus</italic> and the methicillin-resistant <italic>S. aureus, Bacillus subtilis</italic>, and <italic>B. cereus</italic> and the actinomycin X<sub>2</sub> was more potent.</p>