To prepare BAP from the ammonium sulfate suspension its sold as, spin out the
precipitate for 5 min at 4°C in microfuge, resuspend in
H2O to a concentration of 0.1
units/ul, and centrifuge desalt on Sephadex G25 equilibrated in H2O. Adjust the
desalted BAP with Tris pH 8 to 0.1 M and store at 4° C stable essentially indefinitely.
To 10 ug DNA linearized plasmid or fragments dissolved in 45 ul H2O. Add 5
CB 10 X BAP, preheat to 68°C and add 1 ul BAP (0.1 units/ul Worthington). Incubate
at 68°C for 1/2 hr, add another aliquot of BAP (1 ul) and continue incubation for another
1/2 hr. Then add phenol and chloroform directly to 68°C reaction volume and vortex, do
multiple extractions, add NaCl to 0.2 M and ethanol precipitate as usual.