Characterization of a mazEF Toxin-Antitoxin Homologue from Staphylococcus equorum

Abstract

b Toxin-antitoxin (TA) systems encoded in prokaryotic genomes fall into five types, typically composed of two distinct small molecules, an endotoxic protein and a cis-encoded antitoxin of ribonucleic or proteinaceous nature. In silico analysis revealed seven putative type I and three putative type II TA systems in the genome of the nonpathogenic species strain Staphylococcus equorum SE3. Among these, a MazEF system orthologue termed MazEF seq was further characterized. 5= rapid amplification of cDNA ends (RACE) revealed the expression and the transcriptional start site of mazE seq , indicating an immediately upstream promoter. Heterologous expression of the putative toxin-encoding mazF seq gene imposed growth cessation but not cell death on Escherichia coli. In vivo and in vitro, MazF seq was shown to cleave at UACAU motifs, which are remarkably abundant in a number of putative metabolic and regulatory S. equorum gene transcripts. Specific interaction between MazF seq and the putative cognate antitoxin MazE seq was demonstrated by bacterial two-hybrid analyses. These data strongly suggest that MazEF seq represents the first characterized TA system in a nonpathogenic Staphylococcus species and indicate that MazEF modules in staphylococci may also control processes beyond pathogenicity.

Dormancy within Staphylococcus epidermidis biofilms: a transcriptomic analysis by RNA-seq

“…Red, green, and yellow circles represent fold change values under −1.50, above 1.50, and between −1.50 and 1.50, respectively. Biological processes are translation and biosynthetic processes (a); and tricarboxylic acid cycle, acetyl-CoA catabolic process, coenzyme catabolic process, co-factor catabolic process, acetyl-CoA metabolic process, aerobic respiration, cellular respiration, energy derivation by oxidation of organic compounds, coenzyme metabolic processes (b) toxin-antitoxin module mazEF is highly conserved in Staphylococcus species and was described in detail in S. aureus, where antitoxin MazE binds toxin MazF to neutralize ribonuclease activity (Fu et al 2007) and, more recently, in Staphylococcus equorum (Schuster et al 2013). Despite no alterations in mazF expression between S. epidermidis biofilms grown in the absence or presence of Mg 2+ , mazE gene RPKM was superior to 1.00 in biofilms grown without Mg 2+ .…”

Characterization of a Deinococcus radiodurans MazF: A UACA‐specific RNA endoribonuclease

“…In most cases, MazF toxins require strict sequences for RNA cleavages, which are typically 3–7‐nucleotide (nt) motifs (Miyamoto, Kato, Sekiguchi, Tsuneda & Noda, ; Miyamoto, Yokota, Tsuneda, Noda et al. ; Nariya & Inouye, ; Rothenbacher et al., ; Schifano et al., ; Schuster et al., ; Verma & Bhatnagar, ; Yamaguchi & Inouye, ; Yamaguchi, Nariya, Park, & Inouye, ; Zhang et al., ; Zhu et al., , , ). Thus, microbes may reprogram their translation by shutting down most translation processes or by eliminating specific transcripts to cope with unfavorable surroundings.…”

Toxin-Antitoxin Systems on the Large Defense Plasmid pSYSA of Synechocystis sp. PCC 6803

“…HigB falls in this category (21), but interferases of the widespread RelE and MazF family are particularly well studied. RelE cleaves mRNAs in the ribosomal A site (22), whereas MazF cleaves single-stranded RNAs sequence specifically at ACA sites (23) or is even more selective, cleaving at UACAU, as in the case of the Clostridium difficile and Staphylococcus equorum MazF toxins (24,25).…”