Characteristics of the bacterial strains and the distribution of absent genes detected by microarray.

Range of the lost genes in loci 1–4 is BP0910A-BP0934, BP1135-BP1141, BP1948-BP1966, and BP2088-BP2103, respectively. (+) and (−) indicates presence or absence of the locus. 1.International reference strain 2.Three genes in the locus were lost (BP0910A-BP0912). 3.Strain used for the production of whole cell vaccine in Finland since 1962 and obtained from USA. 4.Strain added to the whole cell vaccine in 1976 and obtained from UK.