Mapping protein-protein interactions in the translocation and assembly module (TAM) complex involved in autotransporter biogenesis

Kesha Josts

Bacterial proteins destined to function extracellularly must efficiently cross two layers of membrane covering the cells.  To do so, numerous transporter systems are employed by specific protein types to ensure the delivery of the proteins to their final destination in their fully functional state. 

Autotransporters are outer membrane-bound proteins that act in the extracellular milleau of the cells.  Recent evidence indicates that autotransporters utilise at least two bacterial transporter systems to make their way to the outside of the cell.  In our lab we are investigating one such transporter system, namely the transport and assembly module (TAM) complex which is involved in the transport of the passenger domain of autotransporters across the outer membrane. 

By utilising several biochemical and biophysical techniques we investigate protein complex formation, as well as attempt to shed some light on which proteins are involved in substrate recognition and binding.  By mapping out the interactions involved in TAM formation as well as how each member of the complex interacts with its substrates we will be able to formulate a mechanistic model of passenger domain translocation and cell surface delivery.


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