Direct detection of stringent alarmones (pp)pGpp using malachite green
Authors:Muriel Schicketanz1, Magdalena Petrová2, Dominik Rejman2, Margherita Sosio3, Stefano Donadio3 and Yong Everett Zhang1
doi: 10.15698/mic2024.08.834
Volume 11, pp. 312 to 320, published 05/08/2024.
1 Department of Biology, University of Copenhagen, DK2200, Copenhagen, Denmark. 2 Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences v.v.i, Prague, Czech Republic. 3 NAICONS Srl, 20139, Milan, Italy.
Keywords:
pppGpp, ppGpp, pGpp, SpoT, malachite green, thermorubin.
Corresponding Author(s):
Conflict of interest statement:
MSo and SD are shareholders of NAICONS, which owns the strain that produced the thermorubin used in this study.
Please cite this article as:
Muriel Schicketanz, Magdalena Petrová, Dominik Rejman, Margherita Sosio, Stefano Donadio, Yong Everett Zhang (2024). Direct detection of stringent alarmones (pp)pGpp using malachite green. Microbial Cell 11: 312-320. doi: 10.15698/mic2024.08.834
© 2024 Schicketanz et al. This is an open-access article released under the terms of the Creative Commons Attribution (CC BY) license, which allows the unrestricted use, distribution, and reproduction in any medium, provided the original author and source are acknowledged.
Abstract:
The alarmone (p)ppGpp serves as the signalling molecule for the bacterial universal stringent response and plays a crucial role in bacterial virulence, persistence, and stress adaptation. Consequently, there is a significant focus on developing new drugs that target and modulate the levels of (p)ppGpp as a potential strategy for controlling bacterial infections. However, despite the availability of various methods for detecting (p)ppGpp, a simple and straightforward detection method is needed. In this study, we demonstrated that malachite green, a well-established compound used for phosphate detection, can directly detect (p)ppGpp and its analogues esp., pGpp. By utilizing malachite green, we identified three new inhibitors of the hydrolase activity of SpoT, one of the two RelA-SpoT homolog (RSH) proteins responsible for making and hydrolyzing (p)ppGpp in Escherichia coli. These findings highlight the convenience and practicality of malachite green, which can be widely employed in high-throughput studies to investigate (pp)pGpp in vitro and discover novel regulators of RSH proteins.