Antigenic Structure of Brucella suis Spheroplasts

Abstract

BAUGHN, ROBERT E. (University of Tennessee, Memphis), AND BoB A. FREEMAN. Antigenic structure of Brucella suis spheroplasts. J. Bacteriol.. 92:1298-1303. 1966.-Immunoelectrophoresis was used to differentiate between the antigenic mosaics of normal cells of Brucella suis and of spheroplasts prepared by treatment with penicillin, glycine, and a combination of these agents. Smooth cells possessed at least 13 antigens, 10 of which were precipitated with homologous antiserum. Three additional antigens were visualized by reaction with spheroplast antisera. Spheroplasts induced with glycine were the least complex, with only six antigens. Penicillin-glycine spheroplasts were similar, but possessed one additional antigen. Penicillin spheroplasts were the most complex, with eight antigens. Although there appeared to be quantitative differences between the antigens of spheroplasts and normal cells, no completely new antigens were detected in spheroplasts. Serum absorption studies indicated that four antigens were associated with the surface of normal B. suis, none of which occurred in spheroplasts.

Separation of Soluble Brucella Antigens by Gel-Filtration Chromatography

“…The first peak contained most of the DNA and pentose; it also had considerable protein and RNA and most of the dermal toxicity. Immunoelectrophoresis of this fraction showed that it contained the major antigen E and minor antigen f of Baughn and Freeman (2). Since antigens E and f appeared in the void volume, the molecular sizes could not be determined with this gel.…”

“…For interpreting the antigenic analyses in this and previous studies, the precipitating antigens are identified by a code in which negatively charged antigens are given number designations; positively charged and nonmigrating antigens are assigned arabic numerals. Further, strongly precipitating antigens are designated "major," and their numbers or letters appear in either italics or upper case (2). Separation of antigens by gel filtration.…”

“…With this more porous gel, the majority of the first peak appears VOL. 2 in the void volume and contains Antigen f is found in the trailing side indicating partial penetration of th calculated by the method of Andrews a molecular size of 5 X 105. There protein to the first peak and some toxi in the second peak ( Table 2).…”

“…Animal immunization. Immunizing antigens of B. suis 32P and 1330 were prepared, and rabbits were immunized by methods and schedules previously described (2). Seven days after the last injection, the animals were exsanguinated by cardiac puncture.…”

“…Immunological methods. The procedures employed for immunoelectrophoresis of soluble Brucella antigens were given in detail by Baughn and Freeman (2).…”