Pfeifer

Microbiology and Archaea

Prof. Dr. Felicitas Pfeifer

Research Interests

Microbiology of Extremophilic Archaea

The laboratory investigates extremophilic Archaea with special focus on haloarchaea. In particular, we study mechanisms of adaptation in the environment with special focus on the formation of gas-filled protein particles (gas vesicles). Gas vesicle formation is an ideal model system to study archaeal regulatory processes at the level of transcription, translation and posttranslation. Gas vesicles are nanostructures of 150x600 nm size that appear in response to environmental factors. Depending of the amounts produced, they enable to cells to float to the surface of the brine. Major constituent is the small, hydrophobic protein GvpA that forms tightly connected ribs stabilized by a second protein, GvpC, attached to the outer surface. Twelve additional Gvp proteins are required for gas vesicle formation including two regulatory proteins, GvpE and GvpD. A combination of molecular, biochemical and microscopy techniques is used to investigate regulatory mechanism and to analyse aspects of structure formation in vivo and in vitro. We also investigate signal transduction, cell-cell communication and the adhesion of cells to abiotic and biotic surfaces.

Research topics at a glance:

  • Effect of environmental factors on gas vesicle formation; archaeal signal transduction pathways
  • Action of the GvpE as activator; interaction with proteins of the basal transcription initation complex
  • Action of the GvpE as activator; interaction with proteins of the basal transcription initation complex
  • Structure and aggregation of GvpA; biotechnological aspects of this protein membrane
  • Cell-cell aggregation and outer surface structures such as pili and flagella