KSUCVM - Research - Potential of Natural Antibiotics

K-State and UCLA Scientists Evaluate the Potential of Natural Antibiotics

Our war with microbes continues and, on many fronts, we are losing. The emergence of bacteria that are resistant to most of the available synthetic Porcine Micrograph

antibiotics is becoming increasingly frequent and the availability of new drugs to fight these microbes is limited. Scientists at Kansas State University's College of Veterinary Medicine and the College of Medicine at UCLA have discovered a natural antibiotic in the epithelial cells of the porcine tongue (brown staining cells in the micrograph). This peptide porcine B-defensin-1, kills multi-resistant bacteria such as Salmonella DT104, and is even more potent when used in conjunction with another porcine natural antibiotic, PR-39. K-State scientists, Chris Ross, Frank Blecha, Hua Wu, and Guolong Zhang (left to right) cloned and isolated this new antimicrobial peptide. In conjunction with their colleagues at UCLA, Tom Ganz, and Jishu Shi, they are working to understand the regulation and expression of these natural antibiotics with the goal of adding these new antibiotics to the arsenal of weapons used against microbes. The USDA has continuously funded this work through the National Research Initiative Competitive Grant Program for the last six years.

For more information:

Zhang, G., H. Wu, J. Shi, T. Ganz, C.R. Ross, and F. Blecha. 1998. Molecular cloning and tissue expression of porcine B-defensin 1. FEBS Lett. 424:37-40.

Wu, H., G. Zhang, C.R. Ross, and F. Blecha. 1999. Cathelicidin gene expression in porcine tissues: roles in ontogeny and tissue specificity. Infect. Immun. 67:439-442.

Shi, J., G. Zhang, H. Wu, C. Ross, F. Blecha, and T. Ganz. 1999. Porcine epithelial B-defensin-1 is expressed in the dorsal tongue at antimicrobial concentrations. Infect. Immun. 67:3121-3127.

Zhang, G., H. Hiraiwa, H. Yasue, H. Wu, C.R. Ross, D.Troyer, and F. Blecha. 1999. Cloning and characterization of the gene for a new epithelial B-defensin: genomic structure, chromosomal localization, and evidence for its constitutive expression. J. Biol. Chem. 274:24031-24037.

Korthuis, R.J., D.C. Gute, F. Blecha, and C. Ross. 1999. PR-39, a proline/arginine-rich antimicrobial peptide prevents postischemic microvascular dysfunction. Am. J. Physiol. 277 (Heart Circ. Physiol. 46): H1007-H1013.