PvAMT1;1, a highly selective ammonium transporter that functions as H+/NH4(+) symporter.

ABSTRACT: One of the main forms of nitrogen assimilated by microorganisms and plants is ammonium, despite its toxicity at low millimolar concentrations. Ammonium absorption has been demonstrated to be carried out by highly selective plasma membrane-located transporters of the AMT/MEP/Rh family and characterized by the presence of a well conserved hydrophobic pore through which ammonia is proposed to move. However, uncertainties exist regarding the exact chemical species transported by these membrane proteins, which can be in the form of either hydrophobic ammonia or charged ammonium. Here, we present the characterization of PvAMT1;1 from the common bean and demonstrate that it mediates the high affinity (micromolar), rapidly saturating (1 mM) electrogenic transport of ammonium. Activity of the trans

SUBMITTER: Ortiz-Ramirez C 

PROVIDER: S-EPMC3173114 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature