Disease relevance of dnaB

• A dnaB gene encoding a homologue of the Escherichia coli DNA helicase DnaB was cloned and sequenced in the thermophilic eubacterium Rhodothermus marinus, predicting a DnaB protein that harbors an intein [1].
• Using this transducing phage, it was shown through complementation and protein analyses, that the ts121 mutation is located in the dnaB gene [2].
• Within the region of the Bacillus subtilis chromosome assigned to us in the genome sequencing project, we found a gene, the product of which is similar to the DnaB protein (replicative DNA helicase) of Escherichia coli [3].

High impact information on dnaB

• The mutational insertion event in ts121 was mapped precisely between base pairs 1514 and 1515 of the dnaB gene [2].
• The dnaA initiator protein binds specific sequences in the 245-base pair Escherichia coli origin (oriC) to form a series of complexes which eventually are opened enough to admit dnaB helicase into a prepriming complex (Bramhill, D., and Kornberg, A. (1988) Cell 52, 743-755) [4].
• Present studies demonstrate that the dnaC gene product binds ribonucleotides independent of dnaB protein [5].
• The lambda P protein, which interacts with dnaB protein in the bacteriophage lambda DNA replication, does not bind ATP in the presence or absence of dnaB protein [5].
• Similar kinetics were observed in parallel with filament formation induced by incubation of a dnaB mutant of E. coli at the nonpermissive temperature [6].

Biological context of dnaB

• Regulation of dnaB function in DNA replication in Escherichia coli by dnaC and lambda P gene products [5].

Analytical, diagnostic and therapeutic context of dnaB

• Tryptic peptide mapping demonstrates that ATP cross-links to only the 33-kDa tryptic fragment (Fragment II) of dnaB protein [5].

References