Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/15/1999
Publication Date: N/A
Technical Abstract: Brachyspira pilosicoli (Bp) is the etiologic agent of porcine intestinal spirochetosis (PIS), a recently described diarrheal disease of growing pigs. To determine the role of outer membrane proteins (OMPs) in the development of PIS, we refined a technique for isolating Bp membrane vesicles by osmotic shock. Membranes were obtained by vortexing Bp cells in distilled water followed by centrifugation to remove unbroken cells and ultracentrifugation of the resulting supernatant. The membranes were separated by density into low and high density membrane fractions (LD-membranes and HD-membranes, respectively) and a flagella fraction. Both membrane fractions were shown to be free of flagella and cytoplasmic proteins. Penicillin binding proteins were enriched in the HD-membranes and a 29 KDa OMP was enriched in the LD-membranes. Cholesterol and lipooligosaccharide, but not peptidoglycan, were detected in both fractions. The SDS-PAGE profiles of LD-membranes and HD-membranes differe and an N-terminal amino acid sequence obtained from the 45 KDa major HD-membrane protein showed homology with a surface exposed protein of B. hyodysenteriae (vsp). The findings provide a basis for further characterization of individual membrane proteins and elucidation of their role in PIS.