Isolation and partial characterization of a lipopolysaccharide from phase II Coxiella burnetii

Abstract

A lipopolysaccharide (LPS) was isolated by hot phenol–water extraction from phase II Coxiella burnetii. The LPS was isolated from organisms that had a history of 95 serial yolk sac passages and others that were cloned. The chemical composition of the LPS was partially determined and compared with that of LPS previously isolated from phase I organisms. Most of the sugars present in phase I LPS were detected in phase II LPS; however, there were some quantitative and qualitative differences. The fatty acid profiles of phase I and II LPS were identical. The amount of LPS extracted from phase II organisms was about [Formula: see text] the amount extracted from phase I C. burnetii. Limulus lysate gelation was observed with subnanogram amounts of both phase I and II LPS. In complement fixation tests, both LPSs reacted only with antisera containing antibodies versus phase I antigen. Ouchterlony immunodiffusion tests demonstrated immunological identity of the two LPSs.