Molecular Interplay between the Replicative Helicase DnaC and Its Loader Protein DnaI from Geobacillus kaustophilus

Tsai, Kuang‐Lei; Lo, Yi-Ching; Sun, Yuh‐Ju; Hsiao, Chwan‐Deng

doi:10.1016/j.jmb.2009.09.002

Cited by 18 publications

(33 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Crystal structures of the C-terminal domains of A. aeolicus DnaC [49] and Geobacillus kaustophilus DnaI [57] reveal very similar overall structures (Fig. 1C ).…”

Section: Conservation Of Dna Replication Components In Bacteriamentioning

confidence: 99%

“…1B-C ), it might be possible to develop compounds that inhibit multiple essential replication components, yet do not act on unrelated ATPases. The mode of ATP binding has been deduced for all of the replisome-associated AAA+ proteins and key residues comprising binding pockets have been identified [49, 57, 76, 161, 162]. Replicative and non-replicative AAA+ proteins could now be compared to assess similarities and differences in binding sites that could be exploited to design compounds that specifically inhibit bacterial DNA replication.…”

Section: Potential Opportunities For Drug Discoverymentioning

confidence: 99%

See 1 more Smart Citation

Architecture and Conservation of the Bacterial DNA Replication Machinery, an Underexploited Drug Target

Robinson¹,

Causer²,

Dixon

2012

CDT

103

124

View full text Add to dashboard Cite

New antibiotics with novel modes of action are required to combat the growing threat posed by multi-drug resistant bacteria. Over the last decade, genome sequencing and other high-throughput techniques have provided tremendous insight into the molecular processes underlying cellular functions in a wide range of bacterial species. We can now use these data to assess the degree of conservation of certain aspects of bacterial physiology, to help choose the best cellular targets for development of new broad-spectrum antibacterials.DNA replication is a conserved and essential process, and the large number of proteins that interact to replicate DNA in bacteria are distinct from those in eukaryotes and archaea; yet none of the antibiotics in current clinical use acts directly on the replication machinery. Bacterial DNA synthesis thus appears to be an underexploited drug target. However, before this system can be targeted for drug design, it is important to understand which parts are conserved and which are not, as this will have implications for the spectrum of activity of any new inhibitors against bacterial species, as well as the potential for development of drug resistance. In this review we assess similarities and differences in replication components and mechanisms across the bacteria, highlight current progress towards the discovery of novel replication inhibitors, and suggest those aspects of the replication machinery that have the greatest potential as drug targets.

show abstract

“…Crystal structures of the C-terminal domains of A. aeolicus DnaC [49] and Geobacillus kaustophilus DnaI [57] reveal very similar overall structures (Fig. 1C ).…”

Section: Conservation Of Dna Replication Components In Bacteriamentioning

confidence: 99%

Section: Potential Opportunities For Drug Discoverymentioning

confidence: 99%

Architecture and Conservation of the Bacterial DNA Replication Machinery, an Underexploited Drug Target

Robinson¹,

Causer²,

Dixon

2012

CDT

103

124

View full text Add to dashboard Cite

show abstract

“…Previous studies showed that a ring-shaped hexameric DNA helicase forms a complex with either its loader or primase, resulting in the alteration of enzymatic activity [12], [30], [31]. To clarify how cooperativity and functional relevance between DnaC helicase and primosomal proteins in G. kaustophilus are achieved, we determined the duplex unwinding and ATP hydrolysis activities when DnaC helicase is in complex with DnaG or DnaI.…”

Section: Resultsmentioning

confidence: 99%

“…Column fractions were analyzed by SDS-PAGE. Details for construction and protein purification of co-expressed Gk DnaC- Gk DnaI complex have been described previously [12].…”

Section: Methodsmentioning

confidence: 99%

Mutations Altering the Interplay between GkDnaC Helicase and DNA Reveal an Insight into Helicase Unwinding

Liu

Sun

et al. 2011

PLoS ONE

Self Cite

View full text Add to dashboard Cite

Replicative helicases are essential molecular machines that utilize energy derived from NTP hydrolysis to move along nucleic acids and to unwind double-stranded DNA (dsDNA). Our earlier crystal structure of the hexameric helicase from Geobacillus kaustophilus HTA426 (GkDnaC) in complex with single-stranded DNA (ssDNA) suggested several key residues responsible for DNA binding that likely play a role in DNA translocation during the unwinding process. Here, we demonstrated that the unwinding activities of mutants with substitutions at these key residues in GkDnaC are 2–4-fold higher than that of wild-type protein. We also observed the faster unwinding velocities in these mutants using single-molecule experiments. A partial loss in the interaction of helicase with ssDNA leads to an enhancement in helicase efficiency, while their ATPase activities remain unchanged. In strong contrast, adding accessory proteins (DnaG or DnaI) to GkDnaC helicase alters the ATPase, unwinding efficiency and the unwinding velocity of the helicase. It suggests that the unwinding velocity of helicase could be modulated by two different pathways, the efficiency of ATP hydrolysis or protein-DNA interaction.

show abstract

“…For example, the helicase and helicase loader of Gram-positive organisms such as Bacillus subtilis (whose DnaB and DnaC counterparts are known as DnaC and DnaI, respectively) has been shown to form a stable 6:6 complex [69,70]; however, the B. subtilis loader has been reported to act in a different manner, chaperoning the assembly of the helicase around single-stranded DNA as opposed to opening a preformed ring directly [71]. In this regard, the recent imaging of Geobacillus stearothermophilus DnaB in complex with the B. subtilis DnaI loader (and a fragment of the DnaG primase protein) is notable [72•], in that it exhibits a closed-ring structure that may correspond to a ‘post-assembly’ state (Figure 4d).…”

Section: Ring Opening Systemsmentioning

confidence: 99%

Loading strategies of ring-shaped nucleic acid translocases and helicases

O’Shea

2014

Current Opinion in Structural Biology

View full text Add to dashboard Cite

Ring-shaped nucleic acid translocases and helicases catalyze the directed and processive movement of nucleic acid strands to support essential transactions such as replication, transcription, and chromosome partitioning. Assembled typically as hexamers, ring helicase/translocase systems use coordinated cycles of nucleoside triphosphate (NTP) hydrolysis to translocate extended DNA or RNA substrates through a central pore. Ring formation presents a topological challenge to the engagement of substrate oligonucleotides, and is frequently overcome by distinct loading strategies for shepherding specific motors onto their respective substrates. Recent structural studies that capture different loading intermediates have begun to reveal how different helicase/translocase rings either assemble around substrates or crack open to allow DNA or RNA strand entry, and how dedicated chaperones facilitate these events in some instances. Both prevailing mechanistic models and remaining knowledge gaps are discussed.

show abstract

Molecular Interplay between the Replicative Helicase DnaC and Its Loader Protein DnaI from Geobacillus kaustophilus

Cited by 18 publications

References 43 publications

Architecture and Conservation of the Bacterial DNA Replication Machinery, an Underexploited Drug Target

Architecture and Conservation of the Bacterial DNA Replication Machinery, an Underexploited Drug Target

Mutations Altering the Interplay between GkDnaC Helicase and DNA Reveal an Insight into Helicase Unwinding

Loading strategies of ring-shaped nucleic acid translocases and helicases

Contact Info

Product

Resources

About