Random cloning of bent DNA segments from Escherichia coli chromosome and primary characterization of their structures.

A simple method for the selective detection of DNA segments containing a sequence-directed static bend was developed. Two-dimensional polyacrylamide gel electrophoresis performed at two different temperatures (60 degrees C and 10 degrees C) can effectively separate a bent DNA from a mixture of normal DNA. Using this method, a bank of plasmids carrying bent DNA inserts from the E. coli total chromosome was constructed. The primary characterization of a set of bent DNA segments randomly cloned from E. coli was presented.