Pigment precursors in white clinical Serratia Marcescens strains.

Abstract

Growth curves were determined for both pigmented and nonpigmented Serratia marcescens strains, and were determined to be identical for both types. Prodigiosin and MBC production were assayed in Nima, 9-3-3 and 9-3-3/WF cultures. This data was used to illustrate that production of the precursors is not on a stoichiometric and utilization basis. Nonpigmented strains were observed to produce faint syntrophic pigments when grown next to strain 9-3-3, and a technique was developed to better visualize this pigment. MBC, supplied in great enough quantities, allowed the foundation of a variety of colors on MMH agar, as well as on TS agar. The range of temperature and the amounts of oxygen necessary for production of these pigments were explored and compared with that of the mutant WF. Antibiotics were also employed. It was determined that, while the production of the probable presursor produced by the clinical strains was less sensitive to temperature than WF's MAP, it was equally sensitive to oxygen concentrations and more sensitive to streptomycin. A model of pigment and precursor formation was developed.