Processing of DNA in replication, repair and recombination pathways in cells of all organisms requires the participation of at least one major single-stranded DNA (ssDNA)-binding protein. This protein protects ssDNA from nucleolytic damage, prevents hairpin formation and blocks DNA reannealing until the processing pathway is successfully completed. Many ssDNA-binding proteins interact physicall...

PriB is a primosomal protein required for replication restart in Escherichia coli. PriB stimulates PriA helicase activity via interaction with single-stranded DNA (ssDNA), but the molecular details of this interaction remain unclear. Here, we report the crystal structure of PriB complexed with a 15 bases oligonucleotide (dT15) at 2.7 A resolution. PriB shares structural similarity with the E.co...

We have found that two DNA repair/recombination proteins localize differentially to the cell poles in competent Bacillus subtilis cells. RecA protein colocalized with competence protein ComGA, and its polar localization largely depended on ComGA and ComK activity, while RecN oscillated between the poles in a minute time frame, independent of any competence factor. Oscillation of RecN arrested u...

In the presence of the Escherichia coli DNA binding protein, single-stranded DNA is resistant to both the endo- and exonucleolytic activities of the recBC DNase. Linear duplex DNA, on the other hand, is unwound at a normal rate, but converted to large, single-stranded fragments which are resistant to further hydrolysis. Therefore, in the presence of the binding protein and linear duplex DNA, th...

3'----5' Exonuclease specific for single-stranded DNA copurified with DNA polymerase of nuclear polyhedrosis virus of silkworm Bombyx mori (BmNPV Pol). BmNPV Pol has no detectable 5'----3' exonuclease activity on single-stranded or duplex DNA. Analysis of the products of 3'----5' exonucleolytic reaction showed that deoxynucleoside monophosphates were released during the hydrolysis of single-str...

Escherichia coli phage PRD1 protein P12, involved in PRD1 DNA replication in vivo, has been highly purified from E. coli cells harbouring a gene XII-containing plasmid. Protein P12 binds to single-stranded DNA as shown by gel retardation assays and nuclease protection experiments. Binding of protein P12 to single-stranded DNA increases about 14% the contour length of the DNA as revealed by elec...

In the pesence of the Escherichia coli DNA binding protein, single-stranded DNA is resistant to both the endoand exonucleolytic activities of the recBC DNase. Linear duplex DNA, on the other hand, is unwound at a normal rate, but converted to large, single-stranded fragments which are resistant to further hydrolysis. Therefore, in the presence of the binding protein and linear duplex DNA, the r...

Footprint competition assays are utilized to study the binding of Xenopus transcription factor A to a variety of single-stranded nucleic acids. The addition of Xenopus oocyte, yeast, or wheat germ 5S RNA as footprint competitors reveals that factor A binds these 5S RNAs with similar affinity. In contrast, factor A does not bind to E.coli 5S RNA or wheat germ tRNA in this assay. Factor A binding...