Crystallization and preliminary X-ray diffraction analysis of SeqA bound to a pair of hemimethylated GATC sites.
Escherichia coli SeqA is a negative regulator of DNA replication. The SeqA protein forms a high-affinity complex with newly replicated DNA at the origin of replication and thus prevents premature re-initiation events. Beyond the origin, SeqA is found at the replication forks, where it organizes newly replicated DNA into higher ordered structures. These two functions depend on SeqA binding to multiple hemimethylated GATC sequences. In an effort to understand how SeqA forms a high-affinity complex with hemimethylated DNA, a dimeric variant of SeqA was overproduced, purified and crystallized bound to a DNA duplex containing two hemimethylated GATC sites. The preliminary X-ray analysis of crystals diffracting to 3 A resolution is presented here.
Department of Biochemistry and Biomedical Sciences, HSC-4N57A, McMaster University, Hamilton ON L8N 3Z5, Canada.
Yu Seon
YS
Chung
Alba
A
Guarné
D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020029:Base Pairing; D001483:Base Sequence; D001665:Binding Sites; D003460:Crystallization; D019175:DNA Methylation; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019281:Dimerization; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006860:Hydrogen Bonding; D007544:Isopropyl Thiogalactoside / Q000494:pharmacology; D008958:Models, Molecular; D009154:Mutation; D009690:Nucleic Acid Conformation; D009711:Nucleotides / Q000737:chemistry / Q000378:metabolism*; D010957:Plasmids; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D017422:Sequence Analysis, DNA; D014961:X-Ray Diffraction
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D009711:Nucleotides; C089746:SeqA protein, E coli; D007544:Isopropyl Thiogalactoside