Disease relevance of dnaC

• A novel dnaC mutation that suppresses priB rep mutant phenotypes in Escherichia coli K-12 [1].
• In contrast to the parental phage, growth of the mutant depends on host dnaB and dnaC functions [2].
• The Bacillus subtilis dnaC gene encodes a protein homologous to the DnaB helicase of Escherichia coli [3].

High impact information on dnaC

• DNA biosynthesis subsequent to all three events will generate predominantly O6-meG X T base pairs as O6meG preferentially pairs with T [4].
• It is also essential for growth of a strain lacking PriA, indicating that it might affect replication fork progression or fork rescue. dnaC suppressors of priA overcome this inviability, especially when RecF, RecO or RecR is inactivated, indicating that RdgC avoids or counters a toxic effect of these proteins [5].
• The gene is located adjacent to the dnaC locus, probably both being in a single operon [6].
• The P-14 gene is transcribed from an upstream promoter, and its transcript extends through dnaT and dnaC [7].
• Similar to dnaG and dnaT, dnaC uses several minor codons; the significance of these minor codons to the low level expression of the protein product in E. coli cells remains to be determined [8].

Chemical compound and disease context of dnaC

• Like its decomposition product fleroxacin but unlike quinolone esters, Ro 23-9424 also inhibited replicative DNA biosynthesis in E. coli [9].

Biological context of dnaC

• Several dnaC mutations have been isolated that suppress phenotypes of some replication restart mutants [1].
• The dnaC gene lacks characteristic promoter structures; neither the "Pribnow box" nor the "-35 sequence" was detected within 222 base pairs upstream from the initiator ATG codon [8].
• The nucleotide sequence of the Escherichia coli dnaC gene and the primary structure of the dnaC protein were determined [8].
• Regulation of dnaB function in DNA replication in Escherichia coli by dnaC and lambda P gene products [10].
• Operon structure of dnaT and dnaC genes essential for normal and stable DNA replication of Escherichia coli chromosome [7].

Associations of dnaC with chemical compounds

• Accordingly, they had altered porins and replicative DNA biosynthesis resistant to fleroxacin [11].
• The compounds showed antibacterial activity and effects on cell morphology, replicative DNA biosynthesis, and gyrase-catalyzed DNA supercoiling that were comparable to those shown by nalidixic acid and by oxolinic acid compounds [12].
• Enzymes involved in tetrahydrofolate metabolism are of particular pharmaceutical interest, as their function is crucial for amino acid and DNA biosynthesis [13].
• RNA and DNA biosynthesis are also impaired by oxygen; this has not been examined for paraquat or nitrofurantoin [14].

Physical interactions of dnaC

• Present studies demonstrate that the dnaC gene product binds ribonucleotides independent of dnaB protein [10].

Other interactions of dnaC

• Others have reported a different type of dnaC mutation, dnaC1331, is able to mimic priB mutant phenotypes [1].
• Unlike other dnaC suppressors, it can only weakly suppress the absence of priA [1].
• An upstream open reading frame, separated by just 2 base pairs from the coding region of dnaC, encodes the COOH-terminal half of the dnaT product (protein i; Masai, H., Bond, M. W., and Arai, K. (1986) Proc. Natl. Acad. Sci. U. S. A. 83, 1256-1260) [8].

Analytical, diagnostic and therapeutic context of dnaC

• Escherichia coli strains containing thermosensitive dnaC alleles were studied by flow cytometry [15].
• The observation by thin-section electron microscopy of two distinct pools of DNA, one apparently phage DNA and the other host DNA, in cells infected with nuclear disruption may be a compartmentalization mechanism which separates the pathways of host DNA degradation and phage DNA biosynthesis [16].

References