Abstract
Anti-gonococcus sera were prepared by injecting rabbits intravenously with washed, live organisms from 18-hour cultures grown on an agar medium containing a tryptic digest of egg-white. 1 The 5 individual strains employed included recently isolated ones and old stock strains which had undergone some 400 transplantations in this laboratory. The rabbits were obtained from a special stock of snuffle-free animals. Sera against a mixture of stock strains and against the protein fraction described in the preceding paper 2 were also prepared.
No antiserum against the non-protein fraction was obtained.
Precipitin reactions were run with each immune serum using as precipitinogens the protein and non-protein fractions prepared from each of the 5 strains. Ring tests were made by stratifying the precipitinogen, in progressive 10-fold dilution, over the serum (diluted with 2 parts of saline) in small tubes of 4 mm. inside diameter. Readings were made after standing at room temperature for one hour.
The table gives a sample of the results of the precipitin tests on the various protein and non-protein fractions, using rabbit immune sera prepared by the injection of (a) whole organisms of one strain, (b) the “nucleoprotein” of that strain, and (c) whole organisms of a mixture of strains. The titers of the “nucleoproteins” were somewhat higher than those of the non-protein fractions.
It is noteworthy that the anti-nucleoprotein serum gave positive tests with the non-protein substances. This probably indicates the presence in the “nucleoprotein” of the reactive substance of the nonprotein fraction, which we believe to be a polysaccharide. In view of the process of purification it may be assumed that the polysaccharide is present as part of the protein aggregate. Another possibility which has not been eliminated is the incomplete removal of the last traces of protein from the non-protein fraction, although it gives no chemical tests for proteins.
Get full access to this article
View all access options for this article.