Lactoferrin

• OMIM: 150210
• UniProt: P02788

Lactoferrin (more precisely: Lactotransferrin, lacteus from latin, Milk and Latin ferrum, iron ' and Latin transferre carry over, ') is a protein found in mammals with multifunctional enzyme activities.

Evolution

Lactoferrin belongs to the protein family of transferrins. Transferrins are not only found in mammals, homologous genes are also found in other vertebrates and invertebrates.

Properties and Occurrence

Lactoferrin has both anti- viral and anti-microbial properties. It acts both as a peptidase ( cleavage of peptides ), so it is assigned to the group of serine proteases as well as an iron -binding protein - similar to the transferrin - and additionally shows deoxyribonuclease and ribonuclease activities, making it the nucleases ( EC 3.1. 21.1 ) has been allocated. It is also a potent inhibitor of tryptase.

Lactoferrin is found in many body fluids of mammals, in which milk, tears, saliva, sweat, vaginal fluid, seminal plasma, nasal and bronchial secretions, and other secretions. It is also located in white blood cells.

Even small amounts make a vast biological activity. One liter of cow's milk contains 0.1 g of lactoferrin. It is saturated only to a small extent with iron and is able to bind more than five times its initial iron charge.

In addition it affects cell division and stimulate cell growth. It also develops immunological effects by promoting the growth of lymphocytes.

Antibacterial protection function

Lactoferrin is used by the body in order to remove bacteria, the vital iron. Since bacteria are essential to rely on iron, the iron depletion has an antibacterial effect. As a protease, lactoferrin is able to destroy several important proteins for the colonization of the pathogen Haemophilus influenzae. In particular, occurring in human breast milk concentration of lactoferrin can prevent respiratory infections often occur in infants with this germ. In addition, in Shigella and pathogenic Escherichia coli, it affects the type III secretion system. Released by leukocytes, it is also part of the immune system.

Viral interactions

Infection with HTLV- 1 via breast milk or seminal plasma are favored by lactoferrin. On the other hand, the protein can prevent the replication of HIV-1.

Use

Several studies in the early 21st century show remarkable results in the treatment of chronic periodontitis.

Because of its broad spectrum of activity, the pharmaceutical industry is interested in this protein. Industrially it is isolated from milk and whey. It is used in baby and sports nutrition, as well as in cosmetics, chewing gum and Functional Foods.

As a study by the Journal of the American Medical Association in 2009 showed that administration of lactoferrin on birthweight babies (< 1500 g birth weight ) can reduce the incidence of sepsis and sepsis -associated mortality significantly and clinically relevant.