DNA binding properties of the hfq gene product of Escherichia coli.
We found that plasmids isolated by alkaline-lysis method occasionally showed abnormal mobility on agarose gel electrophoresis. This abnormality was not detected after phenol extraction of plasmids, indicating that it was caused by proteinous factor(s). A 15-kDa protein was found in the plasmid preparations on SDS-PAGE. The sequence of eighteen N-terminal amino acid residues of the 15-kDa protein was identical with the host factor I (HF-I) encoded by the hfq gene at 95 min on the Escherichia coli chromosome map, which is known to be required for bacteriophage Qbeta replication. The HF-I protein was purified and in vitro DNA binding experiment was carried out. HF-I bound to both supercoiled DNA and linear DNA and the binding of HF-I seemed to be sequence-nonspecific.
Takada
A
A
Department of Bioengineering, Tokyo Institute of Technology, Midori-ku, Yokohama, Japan.
Wachi
M
M
Kaidow
A
A
Takamura
M
M
Nagai
K
K
D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D002845:Chromatography; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004587:Electrophoresis, Agar Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli; D029968:Escherichia coli Proteins; D035001:Host Factor 1 Protein; D034982:Integration Host Factors; D008969:Molecular Sequence Data; D010957:Plasmids
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D035001:Host Factor 1 Protein; D034982:Integration Host Factors; C440502:integration host factor, E coli; D004247:DNA