title: Utilizing DART mass spectrometry to pinpoint halogenated metabolites from a marine invertebrate-derived fungus.
abstract: Prenylated indole alkaloids are a diverse group of fungal secondary metabolites and represent an important biosynthetic class. In this study we have identified new halogenated prenyl-indole alkaloids from an invertebrate-derived Malbranchea graminicola strain. Using direct analysis in real time (DART) mass spectrometry, these compounds were initially detected from hyphae of the fungus grown on agar plates, without the need for any organic extraction. Subsequently, the metabolites were isolated from liquid culture in artificial seawater. The structures of two novel chlorinated metabolites, named (-)-spiromalbramide and (+)-isomalbrancheamide B, provide additional insights into the assembly of the malbrancheamide compound family. Remarkably, two new brominated analogues, (+)-malbrancheamide C and (+)-isomalbrancheamide C, were produced by enriching the growth medium with bromine salts.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, California 95064, USA.
authors.forename: Katharine R
authors.initials: KR
authors.lastname: Watts
authors.forename: Steven T
authors.initials: ST
authors.lastname: Loveridge
authors.forename: Karen
authors.initials: K
authors.lastname: Tenney
authors.forename: Joseph
authors.initials: J
authors.lastname: Media
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Valeriote
authors.forename: Phillip
authors.initials: P
authors.lastname: Crews
mesh_terms: D005658:Fungi / Q000737:chemistry* / Q000378:metabolism; D054879:Halogenation; D026121:Indole Alkaloids / Q000737:chemistry* / Q000302:isolation & purification; D008386:Marine Biology; D013058:Mass Spectrometry; D015394:Molecular Structure; D020036:Onygenales / Q000737:chemistry* / Q000378:metabolism; D054876:Prenylation; D012623:Seawater / Q000032:analysis* / Q000737:chemistry*
chemical_list: D026121:Indole Alkaloids; C529354:malbrancheamide