Biosynthesis of Gibberellins in Gibberella fujikuroi. Gibberellin A16

A metabolite isolated from cultures of Gibberella fujikuroi has been deduced from infrared, nuclear magnetic resonance, and mass spectrometric evidence to be the hitherto undescribed gibberellin A16. Cultures supplemented with gibberellin A4-14C yielded radioactive gibberellin A16, whereas those to which gibberellin A7-14C were added yielded unlabeled product. Thus gibberellin A16 is probably formed by direct C-1 hydroxylation of gibberellin A4.