Are many Z-DNA binding proteins actually phospholipid-binding proteins?
We used a Z-DNA affinity column to isolate a collection of Z-DNA binding proteins from a high salt extract of Escherichia coli. We identified one of the major Z-DNA binding proteins of this fraction, not as a protein involved in gene regulation or genetic recombination, but rather as an outer membrane porin protein. We then showed that several other known phospholipid-binding proteins (bovine lung annexins and human serum lipoproteins) also bind much more tightly to Z-DNA than to B-DNA. In all cases, this Z-DNA binding was strongly blocked by competition with acidic phospholipids, such as cardiolipin. Our results raise the question whether many of the Z-DNA binding proteins previously isolated are actually phospholipid-binding proteins.
Department of Medical Biochemistry, University of Calgary, AB, Canada.
P
P
Krishna
B P
BP
Kennedy
D M
DM
Waisman
J H
JH
van de Sande
J D
JD
McGhee
D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism*; D002846:Chromatography, Affinity; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D007700:Kinetics; D008565:Membrane Proteins / Q000302:isolation & purification / Q000378:metabolism*; D008970:Molecular Weight; D009690:Nucleic Acid Conformation; D010743:Phospholipids / Q000378:metabolism* / Q000494:pharmacology; D011089:Polydeoxyribonucleotides
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D008565:Membrane Proteins; D010743:Phospholipids; D011089:Polydeoxyribonucleotides; C019530:poly(dC-dG)