TY  - JOUR
A1  - Eltamany, Enas E.
A1  - Abdelmohsen, Usama Ramadan
A1  - Hal, Dina M.
A1  - Ibrahim, Amany K.
A1  - Hassanean, Hashim A.
A1  - Abdelhameed, Reda F. A.
A1  - Temraz, Tarek A.
A1  - Hajjar, Dina
A1  - Makki, Arwa A.
A1  - Hendawy, Omnia Magdy
A1  - AboulMagd, Asmaa M.
A1  - Youssif, Khayrya A.
A1  - Bringmann, Gerhard
A1  - Ahmed, Safwat A.
T1  - Holospiniferoside: A New Antitumor Cerebroside from The Red Sea Cucumber Holothuria spinifera: In Vitro and In Silico Studies
JF  - Molecules
N2  - Chemical investigation of the methanolic extract of the Red Sea cucumber Holothuria spinifera led to the isolation of a new cerebroside, holospiniferoside (1), together with thymidine (2), methyl-α-d-glucopyranoside (3), a new triacylglycerol (4), and cholesterol (5). Their chemical structures were established by NMR and mass spectrometric analysis, including gas chromatography–mass spectrometry (GC–MS) and high-resolution mass spectrometry (HRMS). All the isolated compounds are reported in this species for the first time. Moreover, compound 1 exhibited promising in vitro antiproliferative effect on the human breast cancer cell line (MCF-7) with IC\(_{50}\) of 20.6 µM compared to the IC50 of 15.3 µM for the drug cisplatin. To predict the possible mechanism underlying the cytotoxicity of compound 1, a docking study was performed to elucidate its binding interactions with the active site of the protein Mdm2–p53. Compound 1 displayed an apoptotic activity via strong interaction with the active site of the target protein. This study highlights the importance of marine natural products in the design of new anticancer agents.
KW  - Holothuria spinifera
KW  - HRMS
KW  - cerebrosides
KW  - molecular docking
KW  - cytotoxicity
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234058
SN  - 1420-3049
VL  - 26
IS  - 6
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  -