Functional or Just Plain Pretty? A Reevaluation of Bacterial Pigment Activity

Journal Title
Journal ISSN
Volume Title
Florida Southern College
Serratia marcescens and Chromobacterium violaceum are both gram-negative opportunistic pathogenetic bacteria that produce the pigments prodigiosin and violacein, respectively. These secondary metabolites have been demonstrated to act as antibiotic compounds effective against pathogenic bacteria, which could be of future therapeutic importance. In this study, the pigments were purified environmental samples of S. marcescens and C. violaceum previously identified as antibiotic producers. These pigments were tested for antibiotic activity under three conditions: individually, together, and in combination with the antibiotic neomycin. No antibiotic activity or enhancement of neomycin was seen in either pigment. Efforts to reactivate the antibiotic production included altering the growth conditions for S. marcescens and C. violaceum and challenging these bacteria with other competing bacterial species. While pigment production was robust, antibiotic activity was not restored. These results demonstrate that the pigment alone does not induce bacteriostatic or bactericidal properties, indicating other cofactors may play a role in antibiotic production within the bacteria.
Honors Thesis Spring 2022
Serratia marcescens, Chromobacterium violaceum, Pigments (Biology), Antibiotic-producing organisms