Tetrapyrrole-mediated regulation in the opportunistic pathogen Pseudomonas aeruginosa

• Applicant: Professorin Dr. Nicole Frankenberg-Dinkel
• Subject Area: Metabolism, Biochemistry and Genetics of Microorganisms
• Term: from 2007 to 2011
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 37415023

In this proposal we seek to elucidate the function of the bacterial phytochrome BphP and a potential heme regulator in Pseudomonas aeruginosa. Phytochromes are biliprotein photoreceptors in plants but their function in bacteria remains elusive. A combination of bioinformatics analyses and reporter gene fusions established a cell-density dependent expression of bphP indicating an involvement of the quorum sensing system and/or the alternative sigma factor RpoS. Proteome and transcriptome analyses will be performed under conditions defined by expression studies to gain insights into the phytochrome regulon of P. aeruginosa. Phytochrome action is dependent on the enzyme heme oxygenase which degrades heme to the phytochrome chromophore. We aim to investigate another possible role of heme oxygenases: the regulation of cellular heme levels through degradation. A potential heme regulator has been identified whose participation in regulating heme degradation and biosynthesis will be tested.

• DFG Programme: Research Grants