Genetic regulation of phenazine-1-carboxamide synthesis by Pseudomonas chlororaphis strain PCL1391

Girard, G. (2006)

Doctoral Thesis

A general overview of regulation of secondary metabolism in Pseudomonas species is given in Chapter 1. Several approaches were combined to identify novel genes involved in the regulation of PCN synthesis and to study their interactions with other regulators. Site-directed mutagenesis was used to test the hypothesis that rpoS is a regulatory gene of PCN synthesis (Chapter 2). To discover additional genes in the regulatory cascade, which already contains psrA and rpoS, a random DNA-fragment microarray of the PCL1391 genome was constructed and used for transcriptomics of the psrA and rpoS mutants (Chapter 3). A random mutagenesis approach resulted in the identification of pip, a novel gene that stimulates PCN production in PCL1391 (Chapter 4). Analyses on the role of Pip as a switch of PCN production depending on environmental conditions are described in Chapter 5. The results described in this thesis are summarized in Chapter 6, where in addition the regulatory network of PCN synthesis in P. chlororaphis PCL1391 is compared to regulatory networks of secondary metabolism in other Pseudomonas species.

• Phenazine
• Pseudomonas
• Secondary metabolism
• TetR homologue
• Stress
• RpoS
• Microarray
• Quorum-sensing
• PsrA

• All authors: Girard, G.
• Supervisor: Lugtenberg, J.E.E.
• Co-supervisor: Bloemberg, G.V.
• Qualification: Doctor (dr.)
• Awarding Institution: Faculty of Science, Leiden University
• Date: 2006-06-06
• ISBN (print): 9789090206219
• Sponsorship: J.E. Jurriaanse Stichting