Transport Ammonium across Procaryotic Membranes

Ammonium transport proteins form highly conserved family of integral membrane proteins present in all domains of life. To understand the transport mechanism of Amt proteins in general, we are using the Af-Amt1 as a model. By combining sitedirected mutagenesis and biochemical, biophysical and crystallographic methods we are investigating the validation of the recruitment site as such, the possibility of ammonium deprotonation and repro tonation events, the substrate ionic form or the role of the Cterminus in transport as well as its function in the interaction with regulatory proteins such as GlnK.