ASSOCIATION OF A 38 KDA BOVINE SERUM-PROTEIN WITH THE OUTER-MEMBRANE OF BORDETELLA-PERTUSSIS

Upon cultivation of Bordetella pertussis in bovine serum, a 38 kDa protein was found to be tightly associated with the outer membrane. The intensity of the 40 kDa porin was reduced under these growth conditions. Exposure of Bordetella pertussis, grown in Stainer and Scholte medium, to bovine serum for 1 h did not result in the appearance of the 38 kDa protein. Unlike the 40 kDa porin however, the electrophoretic mobility of this protein was affected neither by temperature of denaturation nor by the presence of 2-mercaptoethanol. Amino acid sequence analysis of the N-terminal of the 38 kDa protein revealed that his protein had 87% homology to both the mouse and human complement C3 precursors. © 1990.