|MadSci Network: Cell Biology|
The umu/SOS test is used to detect the presence of compounds which can damage DNA, typically used for assessing the presence of DNA damaging (genotoxic) agents in the environment.
The SOS Response is defense mechanism that bacteria have against damage to their DNA. The umu genes are part of the SOS response and are activated in the presence of severe DNA damage to help the bacterial cell survive. Here's a research paper on the SOS response and the role of umu proteins, if you'd like to read more about this interesting bit of science.
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