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HflX is a GTPase that controls hypoxia-induced replication arrest in slow-growing mycobacteria.

ABSTRACT: GTPase high frequency of lysogenization X (HflX) is highly conserved in prokaryotes and acts as a ribosome-splitting factor as part of the heat shock response in Escherichia coli. Here we report that HflX produced by slow-growing Mycobacterium bovis bacillus Calmette-Guérin (BCG) is a GTPase that plays a critical role in the pathogen's transition to a nonreplicating, drug-tolerant state in response to hypoxia. Indeed, HflX-deficient M. bovis BCG (KO) replicated markedly faster in the microaerophilic phase of a hypoxia model that resulted in premature entry into dormancy. The KO mutant displayed hallmarks of nonreplicating mycobacteria, including phenotypic drug resistance, altered morphology, low intracellular ATP levels, and overexpression of Dormancy (Dos) regulon proteins. Mice nasally infected with HflX KO mutant displayed increased bacterial burden in the lungs, spleen, and lymph nodes during the chronic phase of infection, consistent with the higher replication rate observed in vitro in microaerophilic conditions. Unlike fast growing mycobacteria, M. bovis BCG HlfX was not involved in antibiotic resistance under aerobic growth. Proteomics, pull-down, and ribo-sequencing approaches supported that mycobacterial HflX is a ribosome-binding protein that controls translational activity of the cell. With HflX fully conserved between M. bovis BCG and M. tuberculosis, our work provides further insights into the molecular mechanisms deployed by pathogenic mycobacteria to adapt to their hypoxic microenvironment.

SUBMITTER: Ngan JYG

PROVIDER: S-EPMC8000101 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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HflX is a GTPase that controls hypoxia-induced replication arrest in slow-growing mycobacteria.

Ngan Jie Yin Grace JYG Pasunooti Swathi S Tse Wilford W Meng Wei W Ngan So Fong Cam SFC Jia Huan H Lin Jian Qing JQ Ng Sze Wai SW Jaafa Muhammad Taufiq MT Cho Su Lei Sharol SLS Lim Jieling J Koh Hui Qi Vanessa HQV Abdul Ghani Noradibah N Pethe Kevin K Sze Siu Kwan SK Lescar Julien J Alonso Sylvie S

Proceedings of the National Academy of Sciences of the United States of America 20210301 12

GTPase high frequency of lysogenization X (HflX) is highly conserved in prokaryotes and acts as a ribosome-splitting factor as part of the heat shock response in Escherichia coli. Here we report that HflX produced by slow-growing Mycobacterium bovis bacillus Calmette-Guérin (BCG) is a GTPase that plays a critical role in the pathogen's transition to a nonreplicating, drug-tolerant state in response to hypoxia. Indeed, HflX-deficient M. bovis BCG (KO) replicated ...[more]

PMID: 33723035

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Dataset Information

HflX is a GTPase that controls hypoxia-induced replication arrest in slow-growing mycobacteria.

Publications

HflX is a GTPase that controls hypoxia-induced replication arrest in slow-growing mycobacteria.

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