Bartolosides E-K from a Marine Coccoid Cyanobacterium.
The glycosylated and halogenated dialkylresorcinol (DAR) compounds bartolosides A-D (1-4) were recently discovered from marine cyanobacteria and represent a novel family of glycolipids, encoded by the brt biosynthetic gene cluster. Here, we report the isolation and NMR- and MS-based structure elucidation of monoglycosylated bartolosides E-K (5-11), obtained from Synechocystis salina LEGE 06099, a strain closely related to the cyanobacterium that produces the diglycosylated 2-4. In addition, a genome region containing orthologues of brt genes was identified in this cyanobacterium. Interestingly, the major bartoloside in S. salina LEGE 06099 was 1 (above 0.5% dry wt), originally isolated from the phylogenetically distant filamentous cyanobacterium Nodosilinea sp. LEGE 06102. Compounds 5-11 are analogues of 1, with different alkyl chain lengths or halogenation patterns. Their structures and the organization of the brt genes suggest that the DAR-forming ketosynthase BrtD can generate structural diversity by accepting fatty acyl-derived substrates of varying length. Compound 9 features a rare midchain gem-dichloro moiety, indicating that the putative halogenase BrtJ is able to act twice on the same midchain carbon.
Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto , Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal.|Department of Biology, Faculty of Sciences, University of Porto , Rua do Campo Alegre, 4169-007 Porto, Portugal.|Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), University of Porto , Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
Tiago B
TB
Afonso
Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto , Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal.
M Sofia
MS
Costa
Institute of Biological Sciences, Center of Genomic and System Biology, Federal University of Pará (UFPA) , Belém, PA 66075-110, Brazil.
Roberta
R
Rezende de Castro
Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto , Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal.
Sara
S
Freitas
Institute of Biological Sciences, Center of Genomic and System Biology, Federal University of Pará (UFPA) , Belém, PA 66075-110, Brazil.
Artur
A
Silva
Institute of Biological Sciences, Center of Genomic and System Biology, Federal University of Pará (UFPA) , Belém, PA 66075-110, Brazil.
Maria Paula Cruz
MP
Schneider
Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto , Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal.|Centre of Health and Environmental Research-CISA, ESTSP, Polytechnic Institute of Porto , Rua Valente Perfeito 322, 4400-330 Vila Nova de Gaia, Portugal.
Rosário
R
Martins
Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto , Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal.
Pedro N
PN
Leão
D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000458:Cyanobacteria / Q000737:chemistry* / Q000235:genetics; D004354:Drug Screening Assays, Antitumor; D006017:Glycolipids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006801:Humans; D008386:Marine Biology; D015394:Molecular Structure; D005810:Multigene Family; D019906:Nuclear Magnetic Resonance, Biomolecular; D012118:Resorcinols / Q000737:chemistry / Q000302:isolation & purification*
D000970:Antineoplastic Agents; D006017:Glycolipids; D006027:Glycosides; D012118:Resorcinols