The dnaC protein of Escherichia coli. Purification, physical properties and interaction with dnaB protein.
AUTOR(ES)
Lanka, E
RESUMO
E.coli dnaC protein was purified to near-homogeneity in using a dnaC complementation assay [S.Wickner, I.Berkower, M.Wright, and J.Hurwitz (1973) Proc. Natl. Acad. Sci. USA 70, 2369-2373]. Purification was achieved by taking advantage of the hydrophobic interaction of dnaC protein with aliphatic and aromatic matrixes and with Brij58 as stabilizing agent. A sedimentation coefficient for the dnaC protein of 2.6 S corresponding to a molecular weight of approximately 26,000 was estimated from glycerol gradient centrifugation. A polypeptide molecular weight of 28,000 was determined by densitometry on a denaturing gel. In the presence of ATP the dnaC protein forms a complex with dnaB protein [S.Wickner and J.Hurwitz (1975) Proc.Natl.Acad.Sci. USA 72, 921-925]. For the dnaB . dnaC complex a sedimentation coefficient of 14.5 S was measured by glycerol gradient centrifugation, indicating a molecular weight of about 400,000. The ratio of the dnaC and dnaB polypeptides in the complex is approximately 1, as determined on a denaturing gel. It is suggested that the complex consists of the dnaB protein hexamer and six dnaC polypeptides amounting to a calculated molecular weight of about 450,000.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=325772Documentos Relacionados
- Replication of bacteriophage phiK duplex replicative-form DNA in dnaB and dnaC mutants of Escherichia coli.
- Escherichia coli dnaB mutant defective in DNA initiation: isolation and properties of the dnaB protein.
- Helicobacter pylori DnaB helicase can bypass Escherichia coli DnaC function in vivo
- Interaction of P2 bacteriophage with the dnaB gene of Escherichia coli.
- Suppression of dnaC alleles by the dnaB analog (ban protein) of bacteriophage P1.