title: Mechanism of dnaB protein action. I. Crystallization and properties of dnaB protein, an essential replication protein in Escherichia coli.
abstract: Purification and crystallization of dnaB protein from Escherichia coli was performed on a large scale by a simple procedure. From 1.5 kg of cells, 520 mg of dnaB protein were obtained in a 58% yield with a purity greater than 99%. The E. coli cells harbor a high copy-number plasmid carrying the dnaB gene and overproduce the enzyme over 200-fold. The subunit molecular weight determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis is 50,000. Based on a native Mr = 290,000 and cross-linking studies that yielded six bands, dnaB protein is judged to be a hexamer, confirming the results of Reha-Krantz, L. J., and Hurwitz, J. (1978) J. Biol. Chem. 253, 4043-4050.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001426:Bacterial Proteins / Q000302:isolation & purification* / Q000378:metabolism; D003460:Crystallization; D004261:DNA Replication; D004355:Drug Stability; D004926:Escherichia coli / Q000201:enzymology*; D006358:Hot Temperature; D007700:Kinetics; D008970:Molecular Weight; D010744:Phosphoric Monoester Hydrolases / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D010744:Phosphoric Monoester Hydrolases