Disease relevance of dnaB

• Like the Escherichia coli dnaB and SV40 T antigen helicases, therefore, the MCM complex is loaded at origins before initiation and is essential for elongation [1].
• The dnaB protein-primase priming system is also active on uncoated phage G4 and M13 DNAs and on poly(dT) [2].
• It is suggested that suppression of the dnaB mutation by prophage P1 bac is accomplished by a stabilization of dnaB252 by P1 ban subunit molecules in a heteromultimer [3].
• A dnaB-like protein of Pseudomonas aeruginosa [4].
• Interaction of P2 bacteriophage with the dnaB gene of Escherichia coli [5].

High impact information on dnaB

• Here we describe a selection scheme for phage bearing suppressor tRNA plasmids, which relies upon an Escherichia coli host bearing an amber mutation in the dnaB gene [6].
• The dnaB gene is essential for both replication initiation and membrane attachment of the origin region of the chromosome and plasmid pUB110 [7].
• Comparison of the amino acid sequence between the "dnaB protein" and those of other dna genes of Escherichia coli showed no homology, suggesting that the dnaB gene of B. subtilis may be analogous to a hitherto undiscovered gene in E. coli [7].
• A general priming system employing only dnaB protein and primase for DNA replication [2].
• This mutant displays a dominant-lethal phenotype in strains that are heterodiploid for dnaB [8].

Chemical compound and disease context of dnaB

• The effect of adenine ribonucleotides on the stability of Escherichia coli dnaB protein in cellular crude extracts was studied [9].
• The dnaB-like protein is similar to the E. coli dnaB protein with regard to the binding of ATP gamma S and the formation of a ternary complex consisting of the enzyme, ATP gamma S, and phi X174 DNA [4].
• All the isogenic Thy- dnaB mutants of E. coli we have tested show a remarkable immunity towards cell death induced by thymine deprivation at the nonpermissive temperature [10].
• Using a crude Fraction II enzymatic system we have shown that during RNA polymerase action, at least the bacteriophage lambda O and lambda P replication proteins as well as the host dnaB protein must be present to initiate ori lambda-specific DNA replication [11].
• Structure of Escherichia coli dnaC. Identification of a cysteine residue possibly involved in association with dnaB protein [12].

Biological context of dnaB

• The hydrolysis of dnaB protein by trypsin proceeded in two distinct stages in the presence of ATP or ADP [13].
• Genetic and biochemical analyses indicate that the Escherichia coli dnaB replication protein functions in the propagation of replication forks in the bacterial chromosome [14].
• Primer synthesis depends on at least five proteins (DNA binding protein, dnaB and dnaC proteins, protein i, and protein n) and ATP to form a replication intermediate and another protein, primase (dnaG protein), to assemble the oligonucleotide by template transcription [15].
• These observations indicate that the presence of dnaB analog genes in association with R plasmids must be relevant to the plasmid state or to some aspect of conjugative ability [16].
• Similar kinetics were observed in parallel with filament formation induced by incubation of a dnaB mutant of E. coli at the nonpermissive temperature [17].

Associations of dnaB with chemical compounds

• Moreover, the data suggest that the conformation of the dnaB protein complexed with adenosine 5'-O-(3-thiotriphosphate) is different from that complexed with ADP.(ABSTRACT TRUNCATED AT 400 WORDS)[13]
• In the first stage, 14 amino acid residues at the NH2-terminal end were removed and dnaB protein was converted into a fragment with a molecular weight of 50,000 (Fragment I) [13].
• The DNA requirement was best satisfied with either fd or phiX174 single-stranded DNA (Km 0.033 mM nucleotides); maximal rate of nucleoside diphosphate formation occurred with 1 dnaB molecule/fd or phiX174 single-stranded DNA molecule [18].
• The dnaB-like protein has a native molecular weight of about 320,000 as determined by glycerol gradient sedimentation [4].
• Conjugational synthesis of ColI in dnaB recipients, shown primarily to reflect conversion of the transferred DNA into double-stranded material, was also enhanced when the recipients were treated with either rifampin or streptomycin [19].

Other interactions of dnaB

• The dnaB-dnaC replication protein complex of Escherichia coli. I. Formation and properties [20].

Analytical, diagnostic and therapeutic context of dnaB

• This interaction was demonstrated as follows: (a) A complex of dnaB and dnaC(D) gene products was isolated by gel filtration; ATP specifically was required for isolation of the complex [21].
• Purification and crystallization of dnaB protein from Escherichia coli was performed on a large scale by a simple procedure [22].
• The dnaB complementing and ribonucleoside triphosphatase activities could not be separated from each other by affinity chromatography, supporting the finding of others that they both reside on the same protein complex, namely a dnaB multimer [23].
• A dnaB-like protein from P. aeruginosa was purified to near homogeneity using as an assay the immunoprecipitation by E. coli dnaB antiserum in a solid-phase [4].
• The in vitro site-directed mutagenesis method was employed to determine the functional region involved in interaction with dnaB protein [12].

References