The violacein biosynthesis monitored by multi-wavelength fluorescence spectroscopy and by the PARAFAC method

Obtaining information about a biosynthetic pathway is a complex and laborious procedure. In this sense, this work presents a new approach for the initial analysis of the biosynthesis of fluorescent natural products using as example the violacein biosynthesis. For this, a culture of Chromobacterium violaceum was grown in a bioreactor from which aliquots were collected every 2 h for subsequent analysis by multi-wavelength fluorescence spectroscopy. The excitation-emission matrices demonstrated the dynamic behavior of the fluorophores signal that are consumed and produced by the bacterium. These signals were resolved by PARAFAC (parallel factor analysis) method totalizing six pure components. Tryptophan and violacein were identified by comparison to spectra available in the literature. The identification of other fluorophores was critical step due to the lack of a database of fluorescent natural products to compare spectra. Finally, this methodology has great potential to achieve a deeper insight into the biosynthesis of natural products.