Isolation of Antigenic Fractions from Bordetella pertussis by means of Lysozyme

A CONSIDERABLE number of Gram-negative bacteria have been broken up in recent years by means of lysozyme1–4. The results of lysozyme treatment of Bordetella pertussis and the analysis of the resulting antigenic fractions form the subject of this communication. Suspensions (phase I), obtained from 24-h-old liquid shaken cultures, were used. After washing them with distilled water, we adjusted their germ count to 4 to 6 × 1010/ml. with reference to the International Standard for Opacity. We determined the conditions under which lysis would least impair antigenicity and found that our purpose would be best served by using a combined treatment with crystalline lysozyme (100 µg/ml.) and versene (200 µg/ml.) in a 0.03 M tris buffer of pH 8.0 under continuous stirring in a water bath of 37° C for 2–3 h.