CLASSIFICATIONB. bronchiseptica was firsC isolated and identifiedas Bacillus bronchicanis by Ferry in 1910'(43). The name Bacillus bronchicanis was chosensince the organism was isolated from therespiratory tracts of dogs suffering from distemper.After organisms with characteristics identicalto those described by Ferry were isolatedfrom the respiratory tracts of guinea pigs, monkeys,and humans in 1912 and 1913 (45, 146), theorganism was renamed Bacterium bronchisepticus(128). In the ensuing years this bacteriumwas renamed four more times, as follows: Alcaligenesbronchisepticus Bergey (1925), Brucellabronchiseptica Topley and Wilson (1929), Alcaligenesbronchicanis Haupt (1935), and Haemophilusbronchisepticus Wilson and Miles(1946). It was placed in the genera Alcaligenes,Brucella, and Haemophilus due to morphological,growth, and biochemical characteristicswhich were somewhat similar to the characteristicsof members of these genera. Finally, thisbacterium was given its present name whenMoreno-Lopez described the genus Bordetella(in honor of Jules Bordet, who first isolated theorganism causing pertussis) and the species Bordetellabronchiseptica (128).Biochemical and antigenic comparisons, DNAhybridization studies, and phage typing haveindicated a close taxonomic relationship amongthe members of the genus Bordetella. Thesemembers (B. bronchiseptica, B. pertussis, andB. parapertussis) are minute coccobacilli whichare nonmotile or motile by lateral peritrichousflagella, gram negative, and may stain bipolarly.They also possess respiratory metabolism, arenonfermentative, and produce no indole or hydrogensulfide, but they do produce cytochromeoxidase, lysine decarboxylase, and catalase.They do not liquefy gelatin, but do render carbohydratesand litmus milk basic. Furthermore,all three species produce a blue protein calledazurin, which undergoes reduction in the presenceof concentrated cell-free extracts and succinate.Azurin is believed to act as a participantin the electron transport system between cytochromec and cytochrome oxidase (149). Theminimum nutritional requirements of the membersof the genus Bordetella are very similar(Table 1), but they are quite different from thoseof organisms in the genera Haemophilus andBrucella. Bordetella species do not require Xfactor (hematin) or V factor (nicotinamide adeninedinucleotide) (129) and are distinguished
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