Molecular basis for the adaptive evolution of environment sensing by H-NS proteins
- University of Vermont, United States
- King Abdullah University of Science and Technology, Saudi Arabia
Abstract
The DNA-binding protein H-NS is a pleiotropic gene regulator in gram-negative bacteria. Through its capacity to sense temperature and other environmental factors, H-NS allows pathogens like Salmonella to adapt their gene expression to their presence inside or outside warm-blooded hosts. To investigate how this sensing mechanism may have evolved to fit different bacterial lifestyles, we compared H-NS orthologs from bacteria that infect humans, plants, and insects, and from bacteria that live on a deep-sea hypothermal vent. The combination of biophysical characterization, high-resolution proton-less NMR spectroscopy and molecular simulations revealed, at an atomistic level, how the same general mechanism was adapted to specific habitats and lifestyles. In particular, we demonstrate how environment-sensing characteristics arise from specifically positioned intra- or intermolecular electrostatic interactions. Our integrative approach clarified the exact modus operandi for H-NS–mediated environmental sensing and suggests that this sensing mechanism resulted from the exaptation of an ancestral protein feature.
Data availability
NMR chemical shift assignments were deposited at the BMBR https://betadeposit.bmrb.wisc.edu/ with IDs 50239 and 50240
Article and author information
Author details
Funding
King Abdullah University of Science and Technology (FCC/1/1976-25)
- Xiaochuan Zhao
National Institute of General Medical Sciences (R01GM129431)
- Jianing Li
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Yibing Shan, Antidote Health Foundation, United States
Version history
- Received: April 1, 2020
- Accepted: January 6, 2021
- Accepted Manuscript published: January 7, 2021 (version 1)
- Version of Record published: January 20, 2021 (version 2)
Copyright
© 2021, Zhao et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Molecular basis for the adaptive evolution of environment sensing by H-NS proteins
eLife 10:e57467.
https://doi.org/10.7554/eLife.57467
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