RESUMO
Coxiella burnetii is the causative agent of Q fever. The bacterium is extremely infectious and is classified as a category biological weapon. A lipopolysaccharide I (LPS I) belongs to the main components of the C. burnetii outer membrane and its structure-function relationship studies are of potential interest. Size-exclusion chromatography revealed noticeable differences in distribution and chemical composition of the O-polysaccharide chains in LPS I. It is likely that C. burnetii is capable of synthesizing chemically distinct subclasses of O-specific polysaccharide molecules differing in their antigenic reactivities. Methylation-linkage analysis indicated the presence of terminal virenose (Vir), dihydrohydroxystreptose (Strep), and mannose (Man), 4-substituted Vir, and 4-substituted Man in the O-specific chain. Serological data indicate that Vir and Strep might be involved in the immunobiology of Q fever.
Assuntos
Antígenos de Bactérias/química , Antígenos de Bactérias/imunologia , Lipopolissacarídeos/química , Lipopolissacarídeos/imunologia , Febre Q/imunologia , Febre Q/microbiologia , Animais , Antígenos de Bactérias/isolamento & purificação , Configuração de Carboidratos , Coxiella burnetii/química , Coxiella burnetii/imunologia , Soros Imunes/análise , Lipopolissacarídeos/isolamento & purificação , Febre Q/metabolismo , Coelhos , Relação Estrutura-AtividadeRESUMO
Rickettsia typhi causes endemic typhus, a relatively mild, acute febrile illness characterized by headache and macular rash. It is maintained in rodents and transmitted to humans by flea Xenopsylla cheopis. R. typhi contains a lipopolysaccharide thought to display a noticeable antigenic activity. We examined its structural features and it appears that the O-specific chain of the R. typhi LPS is composed mainly of the alternating Glc and QuiNAc residues linked by 1-->4 bonds.
