The Journal of Medical Microbiology, Vol 28, Issue 2 137-141, Copyright © 1989 by Society for General Microbiology
Comparison of IgG Fc receptors from clinical isolates of Streptococcus zooepidemicus
M. Yarnall and P. R. Widders
Department of Veterinary Microbiology and Pathology, Washington State University, Pullman 99164-7040.
A receptor binding the Fc region of equine immunoglobulin G (IgG) has been
isolated from a heat-extracted preparation of a clinical isolate of
Streptococcus zooepidemicus. This Fc receptor has a Mr of 45 x 10(3) and
was occasionally seen as an apparent trimer of Mr 130 x 10(3). Antibodies
prepared in horses against the receptor could be adsorbed to and eluted
from whole live bacteria, confirming the surface location of this protein.
Another 11 isolates of S. zooepidemicus from horses with pneumonia,
abscesses or endometritis were tested for Fc-receptor activity. Although
the Mr of the Fc receptors varied among isolates, their antigenicity was
conserved. Thus, the Fc receptor is an attractive candidate for application
in the diagnosis of, or protection against, infections with S.
zooepidemicus.
