Nitrate Transporter is a protein compound found in bacteria, specifically Escherichia coli[1].This protein compound is a complex made up of NarK and NarU. NarU has appeared to be a bigger factor in the function than NarK but both are functionally important.
Function
The Nitrate Transporter complex is active in regulation of nitrogen in the bacteria cell [2]. The complex is expected to provide both nitrate and nitrite transport mechanisms [3]. This transport of Nitrate is under speculation of being different than the typical canonical rocker-switch model[4]. On the NarU portion, there are four amino acids that have solid electron density and has a functional value in nitrate regulation. NarK does not seem to have the same electron density for an obvious binding site. In NarU, the transport mechanism was severely hindered when these amino acid sites were mutated. And when the amino acids were mutated, the binding site was prevented by the mutation from completing its function.
Disease
No diseases have been linked to the Nitrate transporter protein and any mutation of this protein does not seems to increase or decrease E. coli's growth or activity [5].
Relevance
The regulation of nitrate in a bacteria cell is necessary in order to maintain homeostasis. Nitrate in the cell needs to be regulated in order to have nitrate serve its purpose in inter-cellular reactions and then be removed when inactive. Environmentally speaking, this process is important because of the nitrogen compounds in the soil are important for plant life.
Structural highlights
The structure of Nitrate transporter does not have many significant sections. NarK is not shown in the picture but the NarU does have amino acids to feature. Specifically Arg87, Arg303, As173, and Tyr261 are four amino acids that have solid electron density and seems to have functional importance. are the four that are the biding site for some of the nitrate that is being transported.