Fig. 2

Analysis of the DNA fragments from in vivo MNase digestion of nucleoid in wild type E. coli (a) and in vitro MNase digestion of purified genomic DNA (b) in agarose gel. a Wild type cells with the empty vector (lanes 2, 3) and MNase-expressing vector (lanes 4-8) were supplemented with arabinose (lane 6), CaCl₂ (lane 5) or both (lanes 3, 7, 8). Digestion reactions were stopped 1 minute (lane 7) or 5 minutes (lanes 3, 5, 8) after CaCl₂ was added. Lanes 1 and 9 show DNA molecular weight marker. b Lane 1, purified wild type genomic DNA; lanes 2-6, a time course of in vitro MNase digestion of the wild type genomic DNA; lane 7, DNA molecular marker