Stimulation of <i>Escherichia coli</i> DNA damage inducible DNA helicase DinG by the single‐stranded DNA binding protein SSB

Cheng, Zishuo; Caillet, Aimee; Ren, Binbin; Ding, Huangen

doi:10.1016/j.febslet.2012.09.032

Cited by 18 publications

(15 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrast, the iron-bound YrdD has very little or no ssDNA binding activity. In controls, whereas the E. coli single-stranded DNA binding protein SSB forms the SSB-ssDNA complex (Shereda et al 2008, Cheng et al 2012), the E. coli iron-sulfur cluster assembly protein IscU, a zinc-bound protein (Ramelot et al 2004), fails to bind any ssDNA (Figure 3B), validating the specific ssDNA binding activity of the zinc-bound YrdD. We also compared the ssDNA binding activity of the zinc-bound YrdD and SSB (Figure 3C).…”

Section: Resultsmentioning

confidence: 63%

“…Recombinant YrdD was expressed in E. coli BL21 strain in either LB (Luria-Bertani) medium or M9 minimal medium supplemented with glucose (0.2%), thiamin (5 μg/ml) and 20 amino acids (each at 10 μg/ml). E. coli YrdD, IscU (Yang et al 2006), topoisomerase I (Lu et al 2011) and the single-stranded DNA binding protein SSB (Cheng et al 2012) were purified following the procedure described previously. The molecular weight of purified YrdD was confirmed by mass spectrometer.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Iron and zinc binding activity of Escherichia coli topoisomerase I homolog YrdD

Cheng

Tan

et al. 2014

Biometals

Self Cite

View full text Add to dashboard Cite

YrdD, a homolog of the C-terminal zinc-binding region of Escherichia coli topoisomerase I, is highly conserved among proteobacteria and enterobacteria. However, the function of YrdD remains elusive. Here we report that YrdD purified from E. coli cells grown in LB media contains both zinc and iron. Supplement of exogenous zinc in the medium abolishes the iron binding of YrdD in E. coli cells, indicating that iron and zinc may compete for the same metal binding sites in the protein. While the zinc-bound YrdD is able to bind single-stranded (ss) DNA and protect ssDNA from the DNase I digestion in vitro, the iron-bound YrdD has very little or no binding activity for ssDNA, suggesting that the zinc-bound YrdD may have an important role in DNA repair by interacting with ssDNA in cells.

show abstract

Section: Resultsmentioning

confidence: 63%

Section: Methodsmentioning

confidence: 99%

Iron and zinc binding activity of Escherichia coli topoisomerase I homolog YrdD

Cheng

Tan

et al. 2014

Biometals

Self Cite

View full text Add to dashboard Cite

show abstract

“…Consistent with this, mutants YejH (recently renamed ‘RadD’) are sensitive to ionizing radiation and induced DSBs (Chen, Byrne, Wood and Cox, personal communication.) In contrast, RadA exhibited synthetic sensitivity to the gap‐producing agent, AZT, but not DSB‐producing CFX, with the DNA damage‐inducible, Fe‐S helicase DinG (Voloshin et al ., ; Voloshin and Camerini‐Otero, ; Ren et al ., ; Cheng et al ., ) and its paralog YoaA. This suggests a novel role for these proteins in replication‐gap processing.…”

Section: Discussionmentioning

confidence: 95%

Genetic analysis of Escherichia coli RadA: functional motifs and genetic interactions

Cooper

Boyle

Lovett

2015

Molecular Microbiology

View full text Add to dashboard Cite

The RadA/Sms protein is a RecA-related protein found universally in eubacteria and plants, implicated in processing of recombination intermediates. Here we show that the putative Zn finger, Walker A motif, KNRXG motif and Lon protease homology domain of the Escherichia coli RadA protein are required for DNA damage survival. RadA is unlikely to possess protease activity as the putative active site serine is not required. Mutants in RadA have strong synergistic phenotypes with those in the branch migration protein RecG. Sensitivity of radA recG mutants to azidothymidine (AZT) can be rescued by blocking recombination with recA or recF mutations or by overexpression of RuvAB, suggesting that lethal recombination intermediates accumulate in the absence of RadA and RecG. Synthetic genetic interactions for survival to AZT or ciprofloxacin exposure were observed between RadA and known or putative helicases including DinG, Lhr, PriA, Rep, RuvAB, UvrD, YejH and YoaA. These represent the first affected phenotypes reported for Lhr, YejH and YoaA. The specificity of these effects sheds new light on the role of these proteins in DNA damage avoidance and repair and implicates a role in replication gap processing for DinG and YoaA and a role in double-strand break repair for YejH.

show abstract

“…A recent study shows that DinG is also involved in resolving stalled transcription complexes (37). Furthermore, E. coli DinG activity is stimulated by the singlestranded DNA-binding protein (SSB) (38), and in some organisms, a nuclease domain is fused to DinG so that the fusion protein may act as a nuclease rather than as a helicase to produce ssDNA (39).…”

Section: Trpd2mentioning

confidence: 99%