B. burgdorferi isolates in this study.

aNumerous B. burgdorferi chromosomal pulsed-field gel electrophoresis (PFGE) types have been identified (e. g., [16], [17], [61].bAt least nine B. burgdorferi rRNA intragenic spacer (IGS) lineages have been defined [57], [58], [74].cOver 20 B. burgdorferi sensu stricto OspC types have been identified [57], [62].dMultilocus sequence typing (MLST) of Margos et al.[67].eNumber of plasmids present (the values for N40, JD1 and 297 were determined in this study and for B31 by Casjens et al.[10]).fIncludes the following plasmids known to have lost from the cultures whose genomes were sequenced: B31, cp9-2 and cp32-5; 297, lp25; and N40, lp28-3 (see also text and footnote c of table 2).