Prodigiosin synthesis in mutants of Serratia marcesens.

Defects in prodigiosin formation by L-forms of Serratia marcescens.

An L-form of Serratia marcescens has previously been shown incapable of producing the red pigment, prodigiosin, characteristic of the parent bacteria. Mutants of S. marcesens, unable to form one or the other of the two prodigiosin precursors, 4-methoxy-2,2'-bipyrrole-5-carboxaldehyde or 2-methyl-3-n-amylpyrrole, were used to test the nature of the L-form defect. The L-forms failed to form suffi...

luxS mutants of Serratia defective in autoinducer-2-dependent 'quorum sensing' show strain-dependent impacts on virulence and production of carbapenem and prodigiosin.

The enzyme LuxS is responsible for the production of autoinducer-2 (AI-2), a molecule that has been implicated in quorum sensing in many bacterial species. This study investigated whether there is a luxS-dependent signalling system in the Gram-negative bacteria Serratia spp. Serratia marcescens is a broad-host-range pathogen and an important cause of nosocomial infections. Production of AI-2 ac...

Effect of polymyxin B on the synthesis of prodigiosin and its precursors in Serratia marcescens.

The LysR Transcription Factor, HexS, Is Required for Glucose Inhibition of Prodigiosin Production by Serratia marcescens.

Generation of many useful microbe-derived secondary metabolites, including the red pigment prodigiosin of the bacterium Serratia marcescens, is inhibited by glucose. In a previous report, a genetic approach was used to determine that glucose dehydrogenase activity (GDH) is required for inhibiting prodigiosin production and transcription of the prodigiosin biosynthetic operon (pigA-N). However, ...

Concomitant synthesis of bacteriocin and bacteriocin inactivator from Serratia marcescens.

We have found that Serratia marcescens strain P & S is bacteriocinogenic. However, the phenotypic expression of bacteriocin activity depends upon the temperature at which the cells are grown. When the organism is grown at 30 to 37 C, no bacteriocin activity can be demonstrated, whereas when it is grown at 39 C bacteriocin activity is readily observed. It appears that the P & S strain concomitan...