UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

The unexpected essentiality of glnA2 in Mycobacterium smegmatis is salvaged by overexpression of the global nitrogen regulator glnR, but not by L-, D-, or iso-glutamine

Rakovitsky, N; Oz, MB; Goldberg, K; Gibbons, S; Zimhony, O; Barkan, D; (2018) The unexpected essentiality of glnA2 in Mycobacterium smegmatis is salvaged by overexpression of the global nitrogen regulator glnR, but not by L-, D-, or iso-glutamine. Frontiers in Microbiology , 9 , Article 2143. 10.3389/fmicb.2018.02143. Green open access

[thumbnail of Published article]
Preview
Text (Published article)
Rakovitsky_fmicb-09-02143.pdf - Published Version

Download (1MB) | Preview
[thumbnail of Supplementary table]
Preview
Text (Supplementary table)
Rakovitsky_Table_1_The Unexpected Essentiality of glnA2 in Mycobacterium smegmatis Is Salvaged by Overexpression of the Global Nitrogen Regulator glnR, but Not.pdf - Accepted Version

Download (612kB) | Preview

Abstract

Nitrogen metabolism plays a central role in the physiology of microorganisms, and Glutamine Synthetase (GS) genes are present in virtually all bacteria. In M. tuberculosis, four GS genes are present, but only glnA1 is essential, whereas glnA2 was shown to be non-essential for in-vitro as well as in-vivo growth and pathogenesis, and is postulated to be involved in D-glutamine and iso-glutamine synthesis. Whilst investigating the activity of an antimicrobial compound in M. smegmatis, we found a spontaneous temperature-sensitive mutant in glnA2 (I133F), and used it to investigate the role of glnA2 in M. smegmatis. We deleted the native glnA2 and replaced it with a mutated allele. This re-created the temperature sensitivity—as after 3–4 seemingly normal division cycles, glnA2 became essential for growth. This essentiality could not be salvaged by neither L, D- nor iso-glutamine, suggesting an additional role of glnA2 in M. smegmatis over its role in M. tuberculosis. We also found that overexpression of the global nitrogen regulator glnR enabled bypassing the essentiality of glnA2, allowing the creation of a complete deletion mutant. The discrepancy between the importance of glnA2 in Mtb and M. smegmatis stresses the caution in which results in one are extrapolated to the other.

Type: Article
Title: The unexpected essentiality of glnA2 in Mycobacterium smegmatis is salvaged by overexpression of the global nitrogen regulator glnR, but not by L-, D-, or iso-glutamine
Open access status: An open access version is available from UCL Discovery
DOI: 10.3389/fmicb.2018.02143
Publisher version: https://doi.org/10.3389/fmicb.2018.02143
Language: English
Additional information: Copyright © 2018 Rakovitsky, Bar Oz, Goldberg, Gibbons, Zimhony and Barkan. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) (http://creativecommons.org/licenses/by/4.0/). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Keywords: mycobacteria, glutamine, glutamine synthetase, nitrogen, metabolism
UCL classification: UCL
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences
URI: https://discovery.ucl.ac.uk/id/eprint/10054926
Downloads since deposit
118Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item