Cytokinins beyond plants: synthesis by Mycobacterium tuberculosis
Authors:Marie I. Samanovic and K. Heran Darwin
doi: 10.15698/mic2015.05.203
Volume 2, pp. 168 to 170, published 04/05/2015.
New York University School of Medicine, Department of Microbiology, New York, NY 10016 USA.
Keywords:
Mycobacterium tuberculosis, proteasome, nitric oxide, LONELY GUY and cytokinins
Corresponding Author(s):
Conflict of interest statement:
The authors declare that there are no conflicts of interest.
Please cite this article as:
Marie I. Samanovic and K. Heran Darwin (2015). Cytokinins beyond plants: synthesis by Mycobacterium tuberculosis. Microbial Cell 2(5): 168-170.
© 2015 Samanovic and Darwin. 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:
Mycobacterium tuberculosis (M. tuberculosis) resides mainly inside macrophages, which produce nitric oxide (NO) to combat microbial infections. Earlier studies revealed that proteasome-associated genes are required for M. tuberculosis to resist NO via a previously uncharacterized mechanism. Twelve years later, we elucidated the link between proteasome function and NO resistance in M. tuberculosis in Molecular Cell, 57 (2015), pp. 984–994. In a proteasome degradation-defective mutant, Rv1205, a homologue of the plant enzyme LONELY GUY (LOG) that is involved in the synthesis of phytohormones called cytokinins, accumulates and as a consequence results in the overproduction of cytokinins. Cytokinins break down into aldehydes that kill mycobacteria in the presence of NO. Importantly, this new discovery reveals for the first time that a mammalian bacterial pathogen produces cytokinins and leaves us with the question: why is M. tuberculosis, an exclusively human pathogen, producing cytokinins?