Transferrin is a class of proteins that are responsible for transporting iron ions in living organisms. According to the ** and function of transferrin, it can be divided into several classifications.
1.Serum transferrin: Serum transferrin is the most common type of transferrin and is found in plasma. It is primarily responsible for transporting iron ions in the body, transporting them from absorbing tissues (e.g., the intestines) to storage tissues (e.g., liver) or feeding active cells. Serum transferrin has two iron-binding sites that form complexes with iron ions.
2.Lactoferrin: Lactoferrin is a type of transferrin found in mammalian milk. It plays an important role in transporting iron ions to newborns in early breast milk. Lactoferrin is similar in structure and function to serum transferrin and also has two iron-binding sites.
3.Cellular transferrin: Cellular transferrin is mainly found inside cells and is involved in intracellular iron transport and storage. Cellular transferrin is structurally similar to serum transferrin and also has iron-binding sites. However, unlike serum transferrin, cellular transferrin is mainly used for the transport and storage of iron ions within cells, rather than iron transport in the body.
4.Placental transferrin: Placental transferrin is a type of transferrin found in the cells of the placenta. It plays an important role in transporting iron ions from the mother to the fetus during fetal development. Placental transferrin is similar in structure and function to serum transferrin.
These are the main classifications of transferrin, each of which plays a different role in the body, but all are closely related to iron transport and metabolism. Through the synergistic effect of these transferrins, the balance of iron in the body and the function of supplying iron ions to cells are maintained.