On pseudomonas indigofera (Voges) Migula and its pigment

Production of the Antimicrobial Secondary Metabolite Indigoidine Contributes to Competitive Surface Colonization by the Marine Roseobacter Phaeobacter sp. Strain Y4I

“…4 and Table 2) (48,55). Previous studies of the chemistry of indigoidine focused on its redox activity and deep blue pigmentation for use as a possible redox state sensor or industrial dye (21,30,33,54). Its biological role as a secondary metabolite, however, remains poorly characterized.…”

“…Its biological role as a secondary metabolite, however, remains poorly characterized. Indigoidine is found in two redox states, an oxidized blue form which is insoluble in water and a reduced colorless form which is water soluble and historically referred to as leucoindigoidine (21,30,33,47,54). It is currently hypothesized that indigoidine is synthesized in the oxidized form and that subsequent reduction is biologically mediated (48,55), possibly by the oxalocrotonate tautomerase encoded by igiF ( Table 2 and Fig.…”

“…This is supported by assays performed with the isolated oxidized compound in either a lyophilized state or solubilized in DMSO (data not shown). Unfortunately, reduction of purified indigoidine requires a strong acid, with reoxidation occurring readily under nonreducing conditions (21,54). These features prevent biological assays with the isolated compound in a reduced state.…”

“…Thus, it could be argued that indigoidine needs to be in the appropriate biological context in order to function as predicted and that this is an important area for future investigation. Indigoidine biosynthesis genes have been identified in a phylogenetically diverse group of microbes, including Alpha-, Beta-, and Gammaproteobacteria, as well as several Streptomyces species (14,21,30,48,55). The biosynthesis operon of Y4I shares the most homology with putative indigoidine biosynthesis genes from the betaproteobacterium Vogesella indigofera (AF088856) that are deposited in GenBank but are not described in the literature (see Fig.…”

A Proposed Biochemical Basis for the Genus Pseudomonas

“…Among these is the so-called Pseudomonas beijerinckii, the insoluble purple pigment of which appears to be the calcium or magnesium salt of tetrahydroxyquinone (Kluyver et al, 1939). Another is possibly Bacillus indigoferus Voges, studied under the name of Pseudomonas indigofera by Elazari-Volcani (1939), the water-insoluble, blue pigment of which was found to differ considerably from indigo. Possibly this organism should be retained under the genus Chromobacterium in which it is at present tentatively classified in the Bergey system (1939).…”