The Sole Mycobacterium smegmatis MazF Toxin Targets tRNA^Lys to Impart Highly Selective, Codon-Dependent Proteome Reprogramming.

ABSTRACT: Survival of mycobacteria, both free-living and host-dependent pathogenic species, is dependent on their ability to evade being killed by the stresses they routinely encounter. Toxin-antitoxin (TA) systems are unique to bacteria and archaea and are thought to function as stress survival proteins. Here, we study the activity of the endoribonuclease toxin derived from the MazEF TA system in Mycobacterium smegmatis, designated MazEF-ms. We first enlisted a specialized RNA-seq method, 5' RNA-seq, to identify the primary RNA target(s) of the MazF-ms toxin. Just two tRNA species, tRNA^Lys-UUU and tRNA^Lys-CUU, were targeted for cleavage by MazF-ms at a single site within their anticodon sequence (UU↓U and CU↓U) to render these tRNAs nonfunctional for protein synthesis.

SUBMITTER: Barth VC 

PROVIDER: S-EPMC7033543 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature