title: Visualizing the spatial distribution of secondary metabolites produced by marine cyanobacteria and sponges via MALDI-TOF imaging.
abstract: Marine cyanobacteria and sponges are prolific sources of natural products with therapeutic applications. In this paper we introduce a mass spectrometry based approach to characterize the spatial distribution of these natural products from intact organisms of differing complexities. The natural product MALDI-TOF-imaging (npMALDI-I) approach readily identified a number of metabolites from the cyanobacteria Lyngbya majuscula 3L and JHB, Oscillatoria nigro-viridis, Lyngbya bouillonii, and a Phormidium species, even when they were present as mixtures. For example, jamaicamide B, a well established natural product from the cyanobacterium Lyngbya majuscula JHB, was readily detected as were the ions that correspond to the natural products curacin A and curazole from Lyngbya majuscula 3L. In addition to these known natural products, a large number of unknown ions co-localized with the different cyanobacteria, providing an indication that this method can be used for dereplication and drug discovery strategies. Finally, npMALDI-I was used to observe the secondary metabolites found within the sponge Dysidea herbacea. From these sponge data, more than 40 ions were shown to be co-localized, many of which were halogenated. The npMALDI-I data on the sponge indicates that, based on the differential distribution of secondary metabolites, sponges have differential chemical micro-environments within their tissues. Our data demonstrate that npMALDI-I can be used to provide spatial distribution of natural products, from single strands of cyanobacteria to the very complex marine assemblage of a sponge.
authors.affiliation: Department of Biology, University of California, San Diego, 9500 Gilman Dr, La Jolla, CA 92093, USA.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Esquenazi
authors.forename: Cameron
authors.initials: C
authors.lastname: Coates
authors.forename: Luke
authors.initials: L
authors.lastname: Simmons
authors.forename: David
authors.initials: D
authors.lastname: Gonzalez
authors.forename: William H
authors.initials: WH
authors.lastname: Gerwick
authors.forename: Pieter C
authors.initials: PC
authors.lastname: Dorrestein
mesh_terms: D000818:Animals; D001685:Biological Factors / Q000737:chemistry / Q000378:metabolism*; D000458:Cyanobacteria / Q000737:chemistry* / Q000145:classification / Q000378:metabolism*; D008968:Molecular Conformation; D011161:Porifera / Q000737:chemistry* / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013237:Stereoisomerism
chemical_list: D001685:Biological Factors