Genetics: Wolff and Von Borstel

Prodigiosin is the only pigment of Serratia that has been subjected to chemical analysis.2' 3 The absorption spectrum of prodigiosin as isolated by Wrede has been presented by Ehrismann and Noethling.4 It has been claimed" that the chemically prepared pigment from the ether extract as obtained by Wrede can be further resolved into two components by column chromatography. The absorption spectrum of the 03 extract in the visible is similar to the spectrum of one of the components of the normal pigment separated by chromatography and has a peak at 500 nl.s.6 If such a component is separable from an induced pigment such as that obtained from the combination of P2 and W1, neither of which has an absorption peak in the visible range, then the synthesis of the pigment of 03 and the red pigment prodigiosin may be related by a common step. Summary-The petroleum ether extracts of the normal HY strain of S. marce8cens and four mutants, W1, 03, P2, P18, have been characterized on the basis of their absorption spectra. None of the absorption curves of the mutants resembles the curve of the pigment extract of the HY strain However, the absorption peaks at 538 m,u and 370 m,u found in the HY strain are also present in the extracts of the red pigment induced by growing the mutant P2 with W1 and Pi8 with 03.