Biological role of lactoferrin.
نویسندگان
چکیده
Lactoferrin is an iron-binding protein closely related in structure to the serum iron transport protein transferrin. Unlike transferrin, only traces are normally present in serum, and it is instead found mainly in milk and other external secretions, and in the secondary granules of neutrophils. Although lactoferrin was first isolated 30 years ago, its biological role remains unclear. Some aspects of its function were discussed about 12 years ago in this journal,' and this review will attempt to reassess the function of lactoferrin in the light of the large amount of new information that has accrued since then. Knowledge of the structure of lactoferrin has been advanced by recent x ray crystallographic studies, and the structure and iron binding properties of lactoferrin are reviewed in detail elsewhere.2 Briefly lactoferrin, like transferrin, reversibly binds two ferric ions, for which synergistic binding of an anion, usually bicarbonate or carbonate, is necessary. However, its affinity constant for iron is 300 times greater than that of transferrin, and even in the presence of a competing iron chelator such as citrate it can retain iron down to pH 3 or less while transferrin loses it at pH 5. Unlike transferrin, lactoferrin is strongly basic. Human lactoferrin has been cloned and sequenced4 and the recombinant protein expressed in baby hamster kidney cells.5 bearing in mind when considering its possible biological function. Human milk contains 3-6-12-5 ,umol/l of iron, and of this only 60-70% is in the whey fraction, the remainder being in the lipid fraction (11-20%) or bound to casein (2-14%). " As a consequence, milk lactoferrin is only 6-8% saturated with iron, presumably because of the difficulty in gaining access to iron in the lipid fraction or casein micelles.
منابع مشابه
Studying Lactoferrin N-Glycosylation
Lactoferrin is a multifunctional glycoprotein found in the milk of most mammals. In addition to its well-known role of binding iron, lactoferrin carries many important biological functions, including the promotion of cell proliferation and differentiation, and as an anti-bacterial, anti-viral, and anti-parasitic protein. These functions differ among lactoferrin homologs in mammals. Although con...
متن کاملSingle strand conformation polymorphisms (SSCPs) in the 5'- flanking region of Lactoferrin gene and its association with milk production traits and somatic cell score in Holstein cattle
Lactoferrin (Lf) is a bioactive protein present in all external secretions such as milk that plays important role in the innate host defense. Therefore, the Lf has a major role in bovine mammary gland defense during mastitis. In this study, 5’-flanking region of bovine Lf gene containing three single nucleotide polymorphisms (SNPs) at positions −602 (T/G), −600 (A/G) ...
متن کاملPolymorphism of 5′ Flanking Region of Lactoferrin Gene in Khuzestan Buffaloes
Lactoferrin is a glycoprotein with molecular weight 80 kDa iron-binding bond, which is composed of 690 amino acids. In most mammalian body fluids such as sweat, semen, tears, and saliva and milk neutrophil granules there. bovine lactoferrin gene be associated with susceptibility/resistance to mastitis and even with some economically important production traits. This study was carried out to det...
متن کاملPolymorphism of 5′ Flanking Region of Lactoferrin Gene in Khuzestan Buffaloes
Lactoferrin is a glycoprotein with molecular weight 80 kDa iron-binding bond, which is composed of 690 amino acids. In most mammalian body fluids such as sweat, semen, tears, and saliva and milk neutrophil granules there. bovine lactoferrin gene be associated with susceptibility/resistance to mastitis and even with some economically important production traits. This study was carried out to det...
متن کاملAnticancer effect of lactoferrin on Gastric Cancer Cell Line AGS
Background: Lactoferrin is a glycoprotein with a molecular weight of 80 kDa, as a member of the transferring family. In recent investigations the important biological properties such as anti microbial, antiviral and anticancer activity of lactoferrin were studied. In the present study, the effect of antitumor induced by lactoferin was evaluated on stomach cancer cell AGS. Materials and Methods...
متن کاملSingle strand conformation polymorphisms (SSCPs) in the 5'- flanking region of Lactoferrin gene and its association with milk production traits and somatic cell score in Holstein cattle
Lactoferrin (Lf) is a bioactive protein present in all external secretions such as milk that plays important role in the innate host defense. Therefore, the Lf has a major role in bovine mammary gland defense during mastitis. In this study, 5’-flanking region of bovine Lf gene containing three single nucleotide polymorphisms (SNPs) at positions −602 (T/G), −600 (A/G) ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Archives of disease in childhood
دوره 67 5 شماره
صفحات -
تاریخ انتشار 1992