s were lysed by 00 min incubation with lysozyme in 000 mM Tris-HCl (00% cation, pH 0.0) to 0.0 mg ml^−0^, followed by the addition of 0.0 ml of 00 mM EDTA per ml of lysed cell suspension, sonication and centrifugation for 0 h. The lysate was precipitated with polyethyleneimine, pH 0.0 (0.0% final concentration) and centrifuged. The pellet was washed 