Lactoferrin: an iron-binding antimicrobial protein against Escherichia coli infection

Abstract

Escherichia coli (E. coli) are the most common aerobic gram-negative bacilli in a normal intestinal tract. They cause most of the intra-abdominal infections, wound infections associated with abdominal surgery, and septicemia. Most of these infections are of endogenous intestinal origin. Lactoferrin (LF) is an iron-binding glycoprotein found in milk and various external secretions. This protein has been found to have a number of biological functions, including antimicrobial, anti-cancer, antioxidant, and immunomodulatory effects. Partial degradation of LF by pepsin can give rise to peptides termed lactoferricin (LFcin) with more potent antimicrobial activity. LF and LFcin have been shown to inhibit the growth of a number of pathogenic bacteria (including E. coli and antibiotic-resistant strains), fungi, and even viruses in both in vitro and in vivo studies. We previously demonstrated that both recombinant porcine LF (pLF) produced from yeast and a synthetic 20-residue porcine LFcin peptide exhibit antimicrobial activity in vitro. In one of our recent studies, we performed pathogen challenges, including pathogenic E. coli, Staphylococcus aureus and Candida albicans, of the digestive tract of a transgenic milk-fed animal model. The results showed that LF has broad spectrum antimicrobial activity in the digestive tract and protects the mucosa of the small intestine from injury. Our following study also revealed that pLF as a feedstuff additive enhances avian immunity, including antibody formation and cell-mediated immunity. All of these results suggest that LF could be a novel natural protein in the treatment and prevention of infections with E. coli or antibiotic-resistant bacteria strains.

Antibacterial Properties of hLf1–11 Peptide onto Titanium Surfaces: A Comparison Study Between Silanization and Surface Initiated Polymerization

“…In a previous study, we introduced the 1-11 antimicrobial sequence of the human lactoferrin protein (hLf), the hLf1-11 peptide, as a potent AMP with capacity to reduce bacterial adhesion on titanium implants 8 . Lactoferrin and Lf-derived peptides have been shown to inhibit viral 14 , fungal 15 , parasitic and bacterial infections [16][17][18] . The antibacterial activity of lactoferrin has been widely documented both in vitro and in vivo for Gram-positive and Gram-negative bacteria 19 .…”

Milk Protein Synthesis in the Lactating Mammary Gland: Insights from Transcriptomics Analyses

“…Among those, of relatively high abundance are CD36 and mucin proteins [80,81]. While a specific biological role for all the proteins associated with the BMP and WPC has not been clearly defined, it appears that at the least some of the latter proteins play a role in the defense mechanisms in the newborn and some appear to be related to human/animal health, particularly lactoferrin [80,83,[85][86][87].…”

Expression levels of JNK associated with polymorphic lactotransferrin haplotypes in human nasopharyngeal carcinoma

“…As a member of the transferrin family, LTF is an iron-binding glycoprotein, and has been demonstrated to have multiple physiological functions. LTF is also present in specific granules of neutrophils (23)(24)(25)(26)(27)(28). Its functions include roles in the immune response and the regulation of bone metabolism.…”

“…Its functions include roles in the immune response and the regulation of bone metabolism. LTF also sequesters essential iron to inhibit bacterial growth, as well as exhibiting non-iron-dependent antibacterial, antitumor, antiviral, antifungal, anti-inflammatory and immunoregulatory activities (23)(24)(25)(26)(27)(28).…”