English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We previously established an Escherichia coli strain capable of re-circularizing linear plasmid DNA by expressing the Mycobacterium tuberculosis Ku (Mt-Ku) and Mycobacterium tuberculosis ligase D (Mt-LigD) proteins from the E.coli chromosome. Repair was predominately mutagenic due to deletions at the termini. We hypothesized that these deletions could be due to a nuclease activity of Mt-LigD that was previously detected in vitro. Mt-LigD has three domains: an N-terminal polymerase domain (PolDom), a central domain with 3'-phosphoesterase and nuclease activity and a C-terminal ligase domain (LigDom). We generated bacterial strains expressing Mt-Ku and mutant versions of Mt-LigD. Plasmid re-circularization experiments in bacteria showed that the PolDom alone had no re-circularization activity. However, an increase in the total and accurate repair was found when the central domain was deleted. This provides further evidence that this central domain does have nuclease activity that can generate deletions during repair. Deletion of only the PolDom of Mt-LigD resulted in a complete loss of accurate repair and a significant reduction in total repair. This is in agreement with published in vitro work indicating that the PolDom is the major Mt-Ku-binding site. Interestingly, the LigDom alone was able to re-circularize plasmid DNA but only in an Mt-Ku-dependent manner, suggesting a potential second site for Ku-LigD interaction. This work has increased our understanding of the mutagenic repair by Mt-Ku and Mt-LigD and has extended the in vitro biochemical experiments by examining the importance of the Mt-LigD domains during repair in bacteria.

Characterization of the roles of the catalytic domains of Mycobacterium tuberculosis ligase D in Ku-dependent error-prone DNA end joining