title: Biosynthetic Studies of 13-Desmethylspirolide C Produced by Alexandrium ostenfeldii (= A. peruvianum): Rationalization of the Biosynthetic Pathway Following Incorporation of (13)C-Labeled Methionine and Application of the Odd-Even Rule of Methylation.
abstract: Understanding the biosynthesis of dinoflagellate polyketides presents many unique challenges. Because of the remaining hurdles to dinoflagellate genome sequencing, precursor labeling studies remain the only viable way to investigate dinoflagellate biosynthesis. However, prior studies have shown that polyketide chain assembly does not follow any of the established processes. Additionally, acetate, the common precursor for polyketides, is frequently scrambled, thus compromising interpretation. These factors are further compounded by low production yields of the compounds of interest. A recent report on the biosynthesis of spirolides, a group belonging to the growing class of toxic spiroimines, provided some insight into the polyketide assembly process based on acetate labeling studies, but many details were left uncertain. By feeding (13)C methyl-labeled methionine to cultures of Alexandrium ostenfeldii, the producing organism of 13-desmethylspirolide C, and application of the odd-even methylation rule, the complete biosynthetic pathway has been established.
authors.affiliation: UNCW Center for Marine Science , 5600 Marvin K. Moss Lane, Wilmington, North Carolina 28409, United States.
authors.forename: Matthew
authors.initials: M
authors.lastname: Anttila
authors.affiliation: UNCW Center for Marine Science , 5600 Marvin K. Moss Lane, Wilmington, North Carolina 28409, United States.
authors.forename: Wendy
authors.initials: W
authors.lastname: Strangman
authors.affiliation: UNCW Center for Marine Science , 5600 Marvin K. Moss Lane, Wilmington, North Carolina 28409, United States.
authors.forename: Robert
authors.initials: R
authors.lastname: York
authors.affiliation: UNCW Center for Marine Science , 5600 Marvin K. Moss Lane, Wilmington, North Carolina 28409, United States.
authors.forename: Carmelo
authors.initials: C
authors.lastname: Tomas
authors.affiliation: UNCW Center for Marine Science , 5600 Marvin K. Moss Lane, Wilmington, North Carolina 28409, United States.
authors.forename: Jeffrey L C
authors.initials: JL
authors.lastname: Wright
mesh_terms: D053898:Biosynthetic Pathways; D004141:Dinoflagellida / Q000737:chemistry* / Q000235:genetics; D008387:Marine Toxins / Q000737:chemistry / Q000378:metabolism*; D008715:Methionine / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism*; D008745:Methylation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D061065:Polyketides; D011908:Rationalization; D013141:Spiro Compounds / Q000737:chemistry / Q000378:metabolism*
chemical_list: C517170:13-desmethylspirolide C; D008387:Marine Toxins; D061065:Polyketides; D013141:Spiro Compounds; C429215:spirolide A; D008715:Methionine; C038344:methionine methyl ester