The cyanobacterial dialkylresorcinol bartolosides were initially reported to feature glycosylated and halogenated moieties. Later, biosynthetic and in vitro studies showed that the chlorinated alkyl chains are utilized for a nucleophilic substitution with free fatty acid carboxylates from primary metabolism, generating bartoloside esters. Here, we applied a workflow based on PCR screening coupled to LC-HRESIMS and molecular network analysis with the aim of discovering additional bartoloside diversity. We report the annotation of 27 bartoloside and bartoloside ester derivatives, including the characterization of two new bartolosides, underlining the breadth of structures generated by bartoloside biosynthetic pathways. Some of the herein reported bartolosides feature hydroxylation in their side chains, a modification that has not been associated with this metabolite family.

CIIMAR Interdisciplinary Centre of Marine and Environmental Research University of Porto Matosinhos 4450 208 Portugal

ICBAS School of Medicine and Biomedical Sciences University of Porto Matosinhos 4450 208 Portugal

RECETOX Research Centre for Toxic Compounds in the Environment Faculty of Science Masaryk University Brno 625 00 Czech Republic

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Dittmann E.; Gugger M.; Sivonen K.; Fewer D. P. Natural Product Biosynthetic Diversity and Comparative Genomics of the Cyanobacteria. Trends Microbiol 2015, 23 (10), 642–652. 10.1016/j.tim.2015.07.008. PubMed DOI

Gavriilidou A.; Kautsar S. A.; Zaburannyi N.; Krug D.; Müller R.; Medema M. H.; Ziemert N. Compendium of specialized metabolite biosynthetic diversity encoded in bacterial genomes. Nat. Microbiol 2022, 7 (5), 726–735. 10.1038/s41564-022-01110-2. PubMed DOI

Pye C. R.; Bertin M. J.; Lokey R. S.; Gerwick W. H.; Linington R. G. Retrospective analysis of natural products provides insights for future discovery trends. Proc. Natl. Acad. Sci. U.S.A. 2017, 114 (22), 5601–5606. 10.1073/pnas.1614680114. PubMed DOI PMC

Afonso T. B.; Costa M. S.; Rezende de Castro R.; Freitas S.; Silva A.; Schneider M. P.; Martins R.; Leao P. N. Bartolosides E-K from a Marine Coccoid Cyanobacterium. J. Nat. Prod 2016, 79 (10), 2504–2513. 10.1021/acs.jnatprod.6b00351. PubMed DOI

Leao P. N.; Nakamura H.; Costa M.; Pereira A. R.; Martins R.; Vasconcelos V.; Gerwick W. H.; Balskus E. P. Biosynthesis-assisted structural elucidation of the bartolosides, chlorinated aromatic glycolipids from cyanobacteria. Angew. Chem., Int. Ed. Engl. 2015, 54 (38), 11063–11067. 10.1002/anie.201503186. PubMed DOI PMC

Reis J. P. A.; Figueiredo S. A. C.; Sousa M. L.; Leao P. N. BrtB is an O-alkylating enzyme that generates fatty acid-bartoloside esters. Nat. Commun. 2020, 11 (1), 1458.10.1038/s41467-020-15302-z. PubMed DOI PMC

Wang M.; Carver J. J.; Phelan V. V.; Sanchez L. M.; Garg N.; Peng Y.; Nguyen D. D.; Watrous J.; Kapono C. A.; Luzzatto-Knaan T.; et al. Sharing and community curation of mass spectrometry data with Global Natural Products Social Molecular Networking. Nat. Biotechnol. 2016, 34 (8), 828–837. 10.1038/nbt.3597. PubMed DOI PMC

Ramos V.; Morais J.; Castelo-Branco R.; Pinheiro Â.; Martins J.; Regueiras A.; Pereira A. L.; Lopes V. R.; Frazão B.; Gomes D.; et al. Cyanobacterial diversity held in microbial biological resource centers as a biotechnological asset: the case study of the newly established LEGE culture collection. J. Appl. Phycol 2018, 30 (3), 1437–1451. 10.1007/s10811-017-1369-y. PubMed DOI PMC

Eusébio N.; Castelo-Branco R.; Sousa D.; Preto M.; D’Agostino P.; Gulder T. A. M.; Leão P. N. Discovery and Heterologous Expression of Microginins from Microcystis aeruginosa LEGE 91341. ACS Synth. Biol. 2022, 11 (10), 3493–3503. 10.1021/acssynbio.2c00389. PubMed DOI PMC

Eungrasamee K.; Incharoensakdi A.; Lindblad P.; Jantaro S. Synechocystis sp. PCC 6803 overexpressing genes involved in CBB cycle and free fatty acid cycling enhances the significant levels of intracellular lipids and secreted free fatty acids. Sci. Rep 2020, 10 (1), 4515.10.1038/s41598-020-61100-4. PubMed DOI PMC

Sallal A. K.; Nimer N. A.; Radwan S. S. Lipid and fatty acid composition of freshwater cyanobacteria. Microbiol 1990, 136 (10), 2043–2048. 10.1099/00221287-136-10-2043. DOI

Shan Y.; Liu Y.; Yang L.; Nie H.; Shen S.; Dong C.; Bai Y.; Sun Q.; Zhao J.; Liu H. Lipid profiling of cyanobacteria Synechococcus sp. PCC 7002 using two-dimensional liquid chromatography with quadrupole time-of-flight mass spectrometry. J. Sep Sci. 2016, 39 (19), 3745–3753. 10.1002/jssc.201600315. PubMed DOI

Menon B. R. K.; Richmond D.; Menon N. Halogenases for biosynthetic pathway engineering: Toward new routes to naturals and non-naturals. Catal. Rev. 2022, 64 (3), 533–591. 10.1080/01614940.2020.1823788. DOI

Martinez S.; Hausinger R. P. Catalytic Mechanisms of Fe(II)- and 2-Oxoglutarate-dependent Oxygenases. JBC 2015, 290 (34), 20702–20711. 10.1074/jbc.R115.648691. PubMed DOI PMC

Mitchell A. J.; Dunham N. P.; Bergman J. A.; Wang B.; Zhu Q.; Chang W.-c.; Liu X.; Boal A. K. Structure-Guided Reprogramming of a Hydroxylase To Halogenate Its Small Molecule Substrate. Biochem 2017, 56 (3), 441–444. 10.1021/acs.biochem.6b01173. PubMed DOI PMC

Nakamura H.; Hamer H. A.; Sirasani G.; Balskus E. P. Cylindrocyclophane Biosynthesis Involves Functionalization of an Unactivated Carbon Center. J. Am. Chem. Soc. 2012, 134 (45), 18518–18521. 10.1021/ja308318p. PubMed DOI PMC

Glasser N. R.; Cui D.; Risser D. D.; Okafor C. D.; Balskus E. P. Accelerating the discovery of alkyl halide-derived natural products using halide depletion. Nat. Chem. 2024, 16 (2), 173–182. 10.1038/s41557-023-01390-z. PubMed DOI PMC

Price M. N.; Dehal P. S.; Arkin A. P. FastTree 2 - Approximately Maximum-Likelihood Trees for Large Alignments. PLoS One 2010, 5 (3), e949010.1371/journal.pone.0009490. PubMed DOI PMC