Fumonisin

9: J Agric Food Chem 2003 May 7;51(10):3000-6

FUM13 Encodes a Short Chain Dehydrogenase/Reductase Required for C-3 Carbonyl Reduction during Fumonisin Biosynthesis in Gibberella moniliformis.

Butchko RA, Plattner RD, Proctor RH.

National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, 1815 North University Street, Peoria, Illinois 61604-3999.

Fumonisins are polyketide-derived mycotoxins produced by the filamentous fungus Gibberella moniliformis (anamorph Fusarium verticillioides). Wild-type strains of the fungus produce predominantly four B-series fumonisins, designated FB(1), FB(2), FB(3), and FB(4). Recently, a cluster of 15 putative fumonisin biosynthetic genes (FUM) was described in G. moniliformis. We have now conducted a functional analysis of FUM13, a gene in the cluster that is predicted by amino acid sequence similarity to encode a short chain dehydrogenase/reductase (SDR). Mass spectrometric analysis of metabolites from FUM13 deletion mutants revealed that they produce approximately 10% of wild-type levels of B-series fumonisins as well as two previously uncharacterized compounds. NMR analysis revealed that the new compounds are similar in structure to FB(3) and FB(4) but that they have a carbonyl function rather than a hydroxyl function at carbon atom 3 (C-3). These results indicate that the FUM13 protein catalyzes the reduction of the C-3 carbonyl to a hydroxyl group and are the first biochemical evidence directly linking a FUM gene to a specific reaction during fumonisin biosynthesis. The production of low levels of FB(1), FB(2), FB(3), and FB(4), which have a C-3 hydroxyl, by the FUM13 mutants suggests that G. moniliformis has an additional C-3 carbonyl reductase activity but that this enzyme functions less efficiently than the FUM13 protein.

PMID: 12720383

[top]


4mg noneto biocompare formulae omd ToxicPlants DictCellBio MolBioDict ( test position ) BioChemical Suppliers

A23187	Actinomycin	Aflatoxin	Anisomycin	Aphidicolin	Ascomycin
Bleomycin	Brefeldin	Cerulenin	Chromomycin	Geldanamycin	Cyclopiazonic acid
Cytochalasin	Forskolin	Fumagillin	Fumonisin	Hypericin	K252a
KT5823	Mitomycin	Nigericin	Ochratoxin	Oligomycin	Mycophenolic acid
Paclitaxel	Patulin	Paxilline	Penitrem	Puromycin	Penicillic acid
Radicicol	Rapamycin	Staurosporine	Sterigmatocystin	Thapsigargin	Tunicamycin
Verruculogen	Wortmannin