title: Subdivision of Mycobacterium tuberculosis into five variants for epidemiological purposes: methods and nomenclature.
abstract: Virulent strains of Mycobacterium tuberculosis isolated from humans are divisible into five variants by using four tests: oxygen requirement (aerobic or microaerophilic), nitrate reductase activity, susceptibility to pyrazinamide (60 micrograms/ml) and susceptibility to thiophene-2-carboxylic acid hydrazide (5 micrograms/ml). The five variants are referred to as Classical human, Asian human, bovine, African I and African II. The relation of these variants to previously described types is discussed. This simple division has been shown to be useful in epidemiological studies.
mesh_terms: D006801:Humans; D008826:Microbial Sensitivity Tests; D008828:Microbiological Techniques; D009169:Mycobacterium tuberculosis / Q000145:classification* / Q000187:drug effects / Q000302:isolation & purification; D009565:Nitrate Reductases / Q000378:metabolism; D010101:Oxygen Consumption; D011718:Pyrazinamide / Q000494:pharmacology; D044469:Racial Groups; D013876:Thiophenes / Q000494:pharmacology
chemical_list: D013876:Thiophenes; C016144:thiophene-2-carboxylic acid hydrazide; D011718:Pyrazinamide; D009565:Nitrate Reductases