A DNA‐Binding Protein Specific for the Early Replicated Region of the Chromosome Obtained from Escherichia coli Membrane Fractions

Abstract

After extensive dialysis of Escherichia coli membranes treated with Triton X‐100, three membrane proteins (A, B and B′) with an affinity for DNA have been isolated and purified. They bind to either double‐stranded or single‐stranded DNA. A and B′ proteins preferentially attach to DNA even in the presence of poly(uridylic acid). Only protein B′ can recognize some base sequence of DNA because pulse‐labelled DNA made at the initiation of replication in a synchronized dnaC mutant has been selectively retained by the protein. Copyright © 1980, Wiley Blackwell. All rights reserved