Restriction enzyme digest of PCR fragments with primers ftsZBf and ftsZBr. (a) Digests with BpmI. (b) Undigested products from a, purified and cut with NsiI. M, BRL 1-kb ladder; 1, 2, 8–12 G. nr. pennsylvanicus, Farina, IL; 6, 7 G. nr. pennsylvanicus, Ann Arbor, MI; 4, 5, G. nr. pennsylvanicus, Norwich, VT; and 3, G. firmus, Gainesville, FL.