Taking advantage of an operon fusion placing the lac operon (responsible for producing beta-galactosidase, a protein which degrades lactose) under the control of an SOS-related protein, a simple colorimetric assay for genotoxicity is possible.

The SOS response allows the cell to survive sudden increases in DNA damage by inducing the expression of multiple factors that serve to promote the integrity of DNA. It is therefore a very important system that needs to be regulated at a large number of different levels.

The SOS response is thought to be a major component of the bacterial response to stress and has been characterized thoroughly in E. coli, where it includes the derepression of 43 genes that orchestrate virtually the entire positive transcriptional response to UV irradiation .

Sep 10, 2004 · We report a mechanistically novel type of defense mechanism that uses a bacterial two-component signal transduction system to induce the SOS response and temporarily inhibit cell division during exposure to β-lactam antibiotics, consequently limiting the bactericidal effects of these drugs.

May 10, 2005 · The M.tuberculosis imuB gene, encoded by the Rv3394c ORF, is in an operon with Rv3395c, a putative RecA-like protein. Most interestingly, both Rv3395c and Rv3394c are damage inducible in M.tuberculosis, and the promoter of Rv3395c has been shown to contain a Mycobacterial SOS box (14,16).

SOS repair refers to the DNA repair mechanism, which makes the use of RecA regulatory protein, to inhibit the repressor activity and to activate the SOS inducer genes to recover DNA damage.

In the bacterium Escherichia coli DNA damaging treatments such as ultraviolet or ionizing radiation induce a set of functions called collectively the SOS response, reviewed here. The regulation of the SOS response involves a repressor, the LexA protein, and an …

The SOS response is a cellular response to DNA damage and is named after the universal distress call SOS – ‘save our ship’ or ‘save our souls.’ Upon DNA damage, the replicative DNA polymerase, pol III, is generally unable to copy noncanonical or damaged DNA and so becomes uncoupled from DNA helicase.

Aug 15, 2013 · The bacterial SOS response is an elaborate program for DNA repair, cell cycle regulation and adaptive mutagenesis under stress conditions. Using sensitive sequence and structure analysis, combined with contextual information derived from comparative genomics and domain architectures, we identify two novel domain superfamilies in the SOS ...

Taking advantage of an operon fusion placing the lac operon (responsible for producing beta-galactosidase, a protein which degrades lactose) under the control of an SOS-related protein, a simple colorimetric assay for genotoxicity is possible.