Structure and conformational dynamics of trichothecene mycotoxins.
A combination of NMR spectroscopy and molecular modeling has been employed to characterize the conformation and dynamics of the macrolide ring in verrucarin A and roridin A, two closely related toxins in the trichothecene mycotoxin family. Longitudinal carbon-13 relaxation times demonstrate the relative flexibility of the macrolide ring. The calculations, NOEs, and scalar vicinal coupling constants show that verrucarin A in CDCl 3 and CD 2Cl 2 predominantly adopts a single, well-defined conformation that matches the crystal structure. In contrast, roridin A is present as a mixture of two conformers.
Steinmetz
Wayne E
WE
Chemistry Department, Pomona College, Claremont, California 91711, USA. wsteinmetz@pomona.edu
Robustelli
Paul
P
Edens
Eric
E
Heineman
David
D
D018360:Crystallography, X-Ray; D018942:Macrolides / Q000737:chemistry; D008968:Molecular Conformation; D015394:Molecular Structure; D009183:Mycotoxins / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular; D013237:Stereoisomerism; D014255:Trichothecenes / Q000737:chemistry*
D018942:Macrolides; D009183:Mycotoxins; D014255:Trichothecenes; C005348:muconomycin A; C038849:roridin A