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Studies on Bacterium Tularense Antigens
[摘要] An investigation of the chemical and physical characteristics of purified B. tularense antigen preparations indicated the presence of at least four and possibly six antigenic components probably derived from the cell wall. The treatment of aqueous suspensions of whole organisms with ethyl ether, and the purification of the extract by salt precipitation, differential centrifugation, and dialysis produced a product which possessed uniform immunogenic activity and reproducible ratios of the various chemical constituents. Electron microscope photographs of such a purified preparation indicated that the material was indistinguishable in electron density from pure cell-wall material prepared by other methods. Lipid extraction of purified preparations yielded an immunogenically active preparation composed of a polysaccharide and an amino acid complex and containing organic P. The reducing sugar value found was almost identical with the calculated value for N-acetyl-glucosamine. Various qualitative tests suggest that the N-acetyl derivative of D-glucose (-D-glucopyranoside) may be the sugar resulting from acid hydrolysis of the polysaccharide moiety. The lipid-free purified antigen preparations were indistinguishable from the initial crude extracts in their immunogenic or serologic activity, except for the greatly increased activity per unit weight of antigen.
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[效力级别]  [学科分类] 生物科学(综合)
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