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bioRxiv · 10.1101/2022.06.29.498085

Sub-operon promoter arrangement of disA facilitates c-di-AMP homeostasis and selective stress responses in M. smegmatis

Singla, M.·Pal, A. K.·Chaudhary, V.·Ghosh, A.
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Abstract

Bacterial second messenger signaling often plays an important role in cellular physiology. In this study, we have attempted to understand how c-di-AMP synthesis and degradation are transcriptionally regulated in M. smegmatis. We have discovered that, although c-di-AMP synthesis gene disA exists in a multi-gene operon; a sub-operon promoter arrangement plays a key role under various stress conditions, keeping its dual function property intact. Further, we learned that c-di-AMP plays a role in the autoregulation of the disA promoter to limit intracellular c-di-AMP concentration. We also identified an alternate start codon within the disA gene which can lead to the synthesis of truncated DisA protein at times using an independent stress-inducible promoter. All in all, this study was helpful to understand how c-di-AMP synthesis is regulated under normal and stress conditions linked to its physiological relevance in M. smegmatis.

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Singla, M., Pal, A. K., Chaudhary, V., Ghosh, A.. 2022-06-29. Sub-operon promoter arrangement of disA facilitates c-di-AMP homeostasis and selective stress responses in M. smegmatis. https://doi.org/10.1101/2022.06.29.498085

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