Table 1.

Seminal events in the history of Aggregatibacter actinomycetemcomitans.

Year	Event	Reference
1912	Klinger describes [Bacterium actinomycetem comitans]	[1]
1929	Topley and Wilson relocate the species to genus Actinobacillus	[2]
1962	King and Tatum describe the close phenotypic similarity of [Actinobacillus actinomycetemcomitans] with [Haemophilus aphrophilus]	[3]
1976	[Actinobacillus actinomycetemcomitans] is associated with periodontitis in adolescents	[4,5]
1979	Extraction and partial characterisation of Ltx, a leukotoxin capable of specific lyse of human polymorphonuclear leukocytes	[6]
1982	The Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, and Kingella (HACEK) group of fastidious, Gram-negative bacteria causing infective endocarditis, is conceived	[7]
1982	Serum antibody levels link [Actinobacillus actinomycetemcomitans] with localized juvenile periodontitis	[8]
1983	Three distinct surface antigens are identified and a particularly high periodontopathogenic potential of serotype b is indicated	[9]
1994	The 530-bp deletion in the ltx promoter region is associated with enhanced expression of Ltx and becomes a marker for the so-called JP2 genotype of [Actinobacillus actinomycetemcomitans]	[10]
2006	A new bacterial genus, Aggregatibacter is created with Aggregatibacter actinomycetemcomitans being the type species	[11]
2008	Clinical follow-up studies unequivocally demonstrate that carriage of the JP2 clone of Aggregatibacter actinomycetemcomitans is linked with aggressive periodontitis	[12]