Linear tetrapyrroles and phytochrome-like sensors in signal transduction of the opportunistic pathogen Pseudomonas aeruginosa

• Applicant: Professorin Dr. Nicole Frankenberg-Dinkel
• Subject Area: Metabolism, Biochemistry and Genetics of Microorganisms
• Term: from 2002 to 2007
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5385900

This proposal focuses on the investigation of the role of linear tetrapyrroles (bilins) in bacterial signal transduction. For many pathogenic bacteria like Pseudomonas aeruginosa heme is an essential source of iron. After uptake, the heme molecule is degraded by heme oxygenases to yield iron, carbon monoxide and biliverdin. The heme oxygenase PigA is only induced under iron limiting conditions, the gene for a second putative heme oxygenase, bphO of this non-photosynthetic bacterium occurs in an operon with the gene bphP encoding a bacterial phytochrome. The major objective of this proposal is the functional characterization of the two heme oxygenases and the formed biliverdins in combination with the bacterial phytochrome-like sensor BphP. The role of BphP in bilin binding and sensing, and its contribution to iron- and heme regulated processes in the overall regulatory network of P. aeruginosa will be determined using a combination of genetic, biochemical and modern methods of proteomics and genomics. Long term consequences for biofilm formation and infection are of general interest.

• DFG Programme: Independent Junior Research Groups
• Major Instrumentation: HPLC-Anlage
• Instrumentation Group: 1350 Flüssigkeits-Chromatographen (außer Aminosäureanalysatoren 317), Ionenaustauscher