Transferrin is a protein that circulates in the plasma and is encoded by the transferrin (TF) gene. The protein contains 678 amino acid residues, 19 disulfide bonds and has a molecular mass of about 80 kDa. Transferrin has a combination of alpha helices and beta sheets that form an N-terminus and a C-terminus domain (1). The iron ion that binds to the protein binds to two tyrosine, one aspartic acid and one histidine residues.
In humans, the major function of transferrin is to regulate the level of free iron ions within cells. Transferrin transports iron from cells (such as intestinal cells and cells of the reticuloendothelial system) to all cells that are dividing within the body. The structure of transferrin enables the protein to properly transport iron throughout circulation. Transferrin has homologous carboxyl and amino domains and each of these domains bind to 1 ion of ferric iron (2). Once at the target cells, (entering via the transferrin receptor), the bound iron ion dissociates in an acidic compartment of the cell. This presence of intracellular iron is necessary for cell division to occur (3). …show more content…
A 2003 study comparing transferrin to hemopexin (an unrelated protein that carries similar functions to the heme group) found identified structural features that allowed for acquisition, transport and release of iron molecules (4). Some of the identified features include a 2-domain protein with flexible hinges. These domains enclosed the bound ligand and provided a stable environment for binding and proper triggering for the release of the
In humans, the major function of transferrin is to regulate the level of free iron ions within cells. Transferrin transports iron from cells (such as intestinal cells and cells of the reticuloendothelial system) to all cells that are dividing within the body. The structure of transferrin enables the protein to properly transport iron throughout circulation. Transferrin has homologous carboxyl and amino domains and each of these domains bind to 1 ion of ferric iron (2). Once at the target cells, (entering via the transferrin receptor), the bound iron ion dissociates in an acidic compartment of the cell. This presence of intracellular iron is necessary for cell division to occur (3). …show more content…
A 2003 study comparing transferrin to hemopexin (an unrelated protein that carries similar functions to the heme group) found identified structural features that allowed for acquisition, transport and release of iron molecules (4). Some of the identified features include a 2-domain protein with flexible hinges. These domains enclosed the bound ligand and provided a stable environment for binding and proper triggering for the release of the