We have investigated the production of indigo-related pigments from indoles
by Nocardia globerula IFO 13510. Three pigments (indigo, a structural isom
er of indigo and an unidentified pigment), coproduced in liquid cultures, w
ere isolated by thin-layer and high-pressure liquid chromatography. The pro
duction of the pigments was dependent on medium composition and on the indo
le concentration in the cultures. In addition, the production of NN'-dimeth
ylindigo from 1-methylindole was observed in liquid cultures.