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bioRxiv · 10.1101/2021.10.15.464524

Effects of dual deletion of glnR and mtrA on expression of nitrogen metabolism genes in Streptomyces venezuelae

Zhu, Y.·Wang, J.·Su, W.·Lu, T.·Li, A.·Pang, X.
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Abstract

GlnR activates nitrogen metabolism genes under nitrogen-limited conditions whereas MtrA represses these genes under nutrient-rich conditions in Streptomyces. In this study, we compared the transcription patterns of nitrogen metabolism genes in a double deletion mutant ({Delta}mtrA-glnR) lacking both mtrA and glnR and in mutants lacking either mtrA ({Delta}mtrA) or glnR ({Delta}glnR). The nitrogen metabolism genes were expressed similarly in {Delta}mtrA-glnR and {Delta}glnR under both nitrogen-limited and nutrient-rich conditions, with patterns distinctly different from that of {Delta}mtrA, suggesting a decisive role for GlnR in the control of nitrogen metabolism genes and further suggesting that regulation of these genes by MtrA is GlnR-dependent. MtrA and GlnR utilize the same binding sites upstream of nitrogen metabolism genes, and we showed stronger in vivo binding of MtrA to these sites under nutrient-rich conditions and of GlnR under nitrogen-limited conditions, consistent with the higher levels of MtrA or GlnR under those respective conditions. In addition, we showed that both mtrA and glnR are auto-regulatory. Our study provides new insights into the regulation of nitrogen metabolism genes in Streptomyces.

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Zhu, Y., Wang, J., Su, W., Lu, T., Li, A., Pang, X.. 2021-10-16. Effects of dual deletion of glnR and mtrA on expression of nitrogen metabolism genes in Streptomyces venezuelae. https://doi.org/10.1101/2021.10.15.464524

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