Effects of low-temperature plasmas on bio-macromolecules and vegetative cells - and bacterial defenses

• Applicant: Professorin Dr. Julia Bandow
• Subject Area: Medical Physics, Biomedical Technology ; Metabolism, Biochemistry and Genetics of Microorganisms
• Term: from 2016 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 326526205

Increasingly, low temperature non-equilibrium plasmas are being investigated in the medical sector with applications ranging from sterilization of medical equipment to exploratory treatment of serious wound infections. We characterize low-pressure and atmospheric-pressure plasma reactors with regards to their sterilization and decontamination properties. We investigated the mechanisms underlying bacterial inactivation by plasma and plasma generated photons and particles and found that bacterial inactivation is time-correlated with the inactivation of essential enzymes sensitive to oxidation.Employing a unique plasma source set-up developed and provided by our collaborator J. Benedikt, we will investigate the damaging effects of plasma ions on vegetative bacterial cells and bio-macromolecules in dry environments and in aqueous solution. To this end we will employ methods established during the first funding period including survival tests, protein fold and activity assays, and mass spectrometry. We will further study mutagenic effects of plasma in bacterial pathogens commonly found in chronic wounds. We identified the redox-regulated chaperon Hsp33 as a bacterial stress protein activated by plasma treatment. We will characterize the mechanism underlying its activation by plasma and investigate if this protein and other stress response proteins are capable of protecting bacterial cells from the damaging effects of plasma.

• DFG Programme: Research Grants