Plant & Animal Genomes XIII Conference

January 15-19, 2005
Town & Country Convention Center
San Diego, CA

Structural And Functional Analysis Of Antimicrobial Peptides In The Bovine Mammary Gland

PETRA REGENHARD¹ , JUDITH REINHARDT¹ , SUSANNE ROOSEN¹ , SVEN PAUL¹ , JENS MICHAEL SCHROEDER² , ERNST KALM¹ , CHRISTIAN LOOFT¹

¹  Christian-Albrechts-University of Kiel, Institute of Animal Breeding and Husbandry, Kiel,Germany

²  Clinic of Dermatology, Venerology and Allergology , University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany

The aim of our project is to investigate the role of antimicrobial peptides for defence mechanisms in the bovine mammary gland. First results showed that ß-defensin genes are expressed in the bovine mammary gland. Furthermore it is known from studies in different species that these kind of peptides have a broad-range of antimicrobial activity. As a prerequisite for further studies a genomic characterization of the ß-defensin region was performed. For isolation of defensin genes two genomic bovine BAC-libraries (no. 750 and no. 754 of RZPD Berlin) have been screened by using defensin consensus primers. Seven novel bovine ß-defensin genes and four pseudogenes were identified and mapped in two BAC contigs spanning 700 kb. Subsequent expression analysis revealed expression of LAP, TAP, EBD, BNBD3, BNBD5, DEFB300 and DEFB401 in the mammary gland. Another antimicrobial peptide, psoriasin, was isolated from bovine dander and characterized by mass spectrometry. As we have first evidence for antimicrobial activity of psoriasin against E. coli a bacterial expression vector was constructed to express the recombinant peptide in E. coli BL21 cells for further investigations.