Structure of mycobacteria: recent developments in defining cell wall carbohydrates and proteins.
Work from this laboratory on the immunogens of Mycobacterium species has focused on those based on carbohydrates (with a view to the development of specific tools for the serodiagnosis of mycobacterioses) and on the cell-wall proteins, as a source of protective immunity and as a means of observing specific delayed-type hypersensitivity. Most mycobacteria are endowed with specific, highly antigenic glycolipids that are powerful for the serodiagnosis of individual mycobacterial infections: e.g., the phenolic glycolipids of Mycobacterium leprae and Mycobacterium bovis, the glycopeptidolipids of the Mycobacterium avium complex, and the acylated trehalose-containing lipooligosaccharides of species such as Mycobacterium kansasii, Mycobacterium szulgai, and Mycobacterium malmoense. A search for analogous structures in Mycobacterium tuberculosis has revealed an antigenic diglycosyl diacylglycerol and the immunogenic phosphomannoinositides. Others have reported on the presence of a novel phenolic glycolipid in the Canetti strain of M. tuberculosis. The dominant carbohydrate-containing antigen of M. tuberculosis (responsible for the high-titer anti-arabinofuranosyl activity in tuberculous sera) is lipoarabinomannan, which has been purified in the native state from M. tuberculosis and shown to contain both phosphatidylinositol and phosphoinositol side-branches. The cell wall of M. tuberculosis--more precisely, the peptidoglycan skeleton--is a source of a few distinct, highly immunogenic protein antigens. The recognition, isolation, and characterization of these antigens will also be described.
Brennan
P J
PJ
Department of Microbiology, Colorado State University, Fort Collins 80523.
D000942:Antigens, Bacterial / Q000032:analysis* / Q000276:immunology; D001426:Bacterial Proteins / Q000032:analysis* / Q000276:immunology; D002241:Carbohydrates / Q000032:analysis* / Q000276:immunology; D002473:Cell Wall / Q000032:analysis / Q000276:immunology; D000939:Epitopes / Q000032:analysis; D006801:Humans; D008070:Lipopolysaccharides / Q000032:analysis; D009161:Mycobacterium / Q000032:analysis* / Q000276:immunology / Q000648:ultrastructure
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D002241:Carbohydrates; D000939:Epitopes; D008070:Lipopolysaccharides