TY - JOUR A1 - Dashti, Yousef A1 - Grkovic, Tanja A1 - Abdelmohsen, Usama Ramadan A1 - Hentschel, Ute A1 - Quinn, Ronald J. T1 - Production of Induced Secondary Metabolites by a Co-Culture of Sponge-Associated Actinomycetes, Actinokineospora sp EG49 and Nocardiopsis sp RV163 JF - MARINE DRUGS N2 - Two sponge-derived actinomycetes, Actinokineospora sp. EG49 and Nocardiopsis sp. RV163, were grown in co-culture and the presence of induced metabolites monitored by H-1 NMR. Ten known compounds, including angucycline, diketopiperazine and beta-carboline derivatives 1-10, were isolated from the EtOAc extracts of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163. Co-cultivation of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163 induced the biosynthesis of three natural products that were not detected in the single culture of either microorganism, namely N-(2-hydroxyphenyl)-acetamide (11), 1,6-dihydroxyphenazine (12) and 5a, 6,11a, 12-tetrahydro-5a, 11a-dimethyl[1,4]benzoxazino[3,2-b][1,4]benzoxazine (13a). When tested for biological activity against a range of bacteria and parasites, only the phenazine 12 was active against Bacillus sp. P25, Trypanosoma brucei and interestingly, against Actinokineospora sp. EG49. These findings highlight the co-cultivation approach as an effective strategy to access the bioactive secondary metabolites hidden in the genomes of marine actinomycetes. KW - co-cultivation KW - induced metabolites KW - sponge-associated actinomyetes KW - NMR fingerprint KW - bioactivity KW - natural products KW - A-D KW - aspergillus fumigatus KW - marine KW - biosynthesis Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-116547 SN - 1660-3397 VL - 12 IS - 5 ER - TY - JOUR A1 - Abdelmohsen, Usama Ramadan A1 - Yang, Chen A1 - Horn, Hannes A1 - Hajjar, Dina A1 - Ravasi, Timothy A1 - Hentschel, Ute T1 - Actinomycetes from Red Sea Sponges: Sources for Chemical and Phylogenetic Diversity N2 - The diversity of actinomycetes associated with marine sponges collected off Fsar Reef (Saudi Arabia) was investigated in the present study. Forty-seven actinomycetes were cultivated and phylogenetically identified based on 16S rRNA gene sequencing and were assigned to 10 different actinomycete genera. Eight putatively novel species belonging to genera Kocuria, Mycobacterium, Nocardia, and Rhodococcus were identified based on sequence similarity values below 98.2% to other 16S rRNA gene sequences available in the NCBI database. PCR-based screening for biosynthetic genes including type I and type II polyketide synthases (PKS-I, PKS-II) as well as nonribosomal peptide synthetases (NRPS) showed that 20 actinomycete isolates encoded each at least one type of biosynthetic gene. The organic extracts of nine isolates displayed bioactivity against at least one of the test pathogens, which were Gram-positive and Gram-negative bacteria, fungi, human parasites, as well as in a West Nile Virus protease enzymatic assay. These results emphasize that marine sponges are a prolific resource for novel bioactive actinomycetes with potential for drug discovery. KW - PKS I KW - Meeresschwämme KW - PKS II KW - NRPS KW - Red sea KW - sponges KW - actinomycetes KW - bioactivity Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-112882 ER -