Alignment of the B. anthracis Sterne DHFR sequence (GenBank accession number AY569129) (BanthSterne) with the DHFR sequences from B. anthracis Ames, Western N. America GT3 Group A1a (West), and Kruger B GT87 Group B1 (Kruger) and from B. cereus (Bcer), B. subtilis (Bsubt), and M. avium (Mavium). Identical residues are shown as white letters on black background. Alignment was accomplished with MacVector 7 (Accelrys, San Diego, Calif.). Gaps introduced to maximize alignment are shown as dashes.