期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2019
卷号：116
期号：39
页码：19659-19664
DOI：10.1073/pnas.1911922116
出版社：The National Academy of Sciences of the United States of America
摘要：Rickettsial diseases have long been diagnosed with serum antibodies cross-reactive against Proteus vulgaris (Weil–Felix reaction). Although Weil–Felix antibodies are associated with the development of immunity, their rickettsial target and contribution to disease pathogenesis are not established. Here, we developed a transposon for insertional mutagenesis of Rickettsia conorii , isolating variants defective for replication in cultured cells and in spotted fever pathogenesis. Mutations in the polysaccharide synthesis operon ( pso ) abolish lipopolysaccharide O-antigen synthesis and Weil–Felix serology and alter outer-membrane protein assembly. Unlike wild-type R. conorii , pso mutants cannot elicit bactericidal antibodies that bind O antigen. The pso operon is conserved among rickettsial pathogens, suggesting that bactericidal antibodies targeting O antigen may generate universal immunity that could be exploited to develop vaccines against rickettsial diseases.
