Lysostaphin expression in mammary glands confers protection against staphylococcal infection in transgenic mice

• Published in: Nature biotechnology 2001-01, Vol.19 (1), p.66-70
• Main Authors: Kerr, David E, Plaut, Karen, Bramley, A. John, Williamson, Christine M, Lax, Alistair J, Moore, Karen, Wells, Kevin D, Wall, Robert J
• Format: Article
• Language: English
• Subjects: Agriculture; Amino Acid Substitution; Animal sciences; Animals; Antibiotics; Asparagine; Bioinformatics; Biological and medical sciences; Biomedical and Life Sciences; Biomedical Engineering/Biotechnology; Biomedicine; Biotechnology; Cattle; Dairy cattle; Dairy industry; Economics; Enzymes; Female; Fundamental and applied biological sciences. Psychology; Genetic Engineering; Genetic technics; Glutamine; Lactation; Life Sciences; Lysine; lysostaphin; Lysostaphin - biosynthesis; Lysostaphin - metabolism; Mammary Glands, Animal - physiology; Mastitis, Bovine - prevention & control; Methods. Procedures. Technologies; Mice; Mice, Transgenic; Milk; Milk - metabolism; Milk - physiology; Pathogens; Peptides; Proteins; Publishing; Recombinant Proteins - biosynthesis; Recombinant Proteins - metabolism; Staphylococcal Infections - prevention & control; Staphylococcus - genetics; Staphylococcus aureus; Staphylococcus infections; Transgenic animals; Transgenic animals and transgenic plants
• ISSN: 1087-0156; 1546-1696
• DOI: 10.1038/83540

Infection of the mammary gland, in addition to causing animal distress, is a major economic burden of the dairy industry. Staphylococcus aureus is the major contagious mastitis pathogen, accounting for approximately 15–30% of infections, and has proved difficult to control using standard management practices. As a first step toward enhancing mastitis resistance of dairy animals, we report the generation of transgenic mice that secrete a potent anti-staphylococcal protein into milk. The protein, lysostaphin, is a peptidoglycan hydrolase normally produced by Staphylococcus simulans . When the native form is secreted by transfected eukaryotic cells it becomes glycosylated and inactive. However, removal of two glycosylation motifs through engineering asparagine to glutamine codon substitutions enables secretion of Gln 125,232 -lysostaphin, a bioactive variant. Three lines of transgenic mice, in which the 5′-flanking region of the ovine β-lactoglobulin gene directed the secretion of Gln 125,232 -lysostaphin into milk, exhibit substantial resistance to an intramammary challenge of 10 4 colony-forming units (c.f.u.) of S. aureus , with the highest expressing line being completely resistant. Milk protein content and profiles of transgenic and nontransgenic mice are similar. These results clearly demonstrate the potential of genetic engineering to combat the most prevalent disease of dairy cattle.