Stress, Multi-cellularity, and the Generation of the Quorum Sensing Peptide EDF.

Bacterial communication via quorum sensing (QS) molecules, as well as toxin-antitoxin (TA) gene modules located on bacterial chromosomes are well-studied mechanisms. is a stress-induced TA system mediating cell death requiring a QS extracellular death factor (EDF), the pentapeptide NNWNN. MazF is an endoribonuclease specific for ACA sites.

Intracellular Localization of the Proteins Encoded by Some Type II Toxin-Antitoxin Systems in Escherichia coli.

Bacterial toxin-antitoxin (TA) systems encode a toxin and an antitoxin that counteracts the toxin. Such TA systems are found abundantly on bacterial chromosomes and on extrachromosomal genetic elements. The toxin is always a protein.

A Bias in the Reading of the Genetic Code of is a Characteristic for Genes that Specify Stress-induced MazF-mediated Proteins.

Background: Escherichia coli (E. coli) mazEF, a stress-induced toxin-antitoxin (TA) system, has been studied extensively. The MazF toxin is an endoribonuclease that cleaves RNAs at ACA sites.

Stress-Induced MazF-Mediated Proteins in Escherichia coli.

is an extensively studied stress-induced toxin-antitoxin (TA) system. The toxin MazF is an endoribonuclease that cleaves RNAs at ACA sites. By that means, under stress, the induced MazF generates a stress-induced translation machinery (STM) composed of MazF-processed mRNAs and selective ribosomes that specifically translate the processed mRNAs.

Quorum Sensing Extracellular Death Peptides Enhance the Endoribonucleolytic Activities of MazF Toxins.

is a toxin-antitoxin module located on chromosomes of most bacteria. MazF toxins are endoribonucleases antagonized by MazE antitoxins. Previously, we characterized several quorum sensing peptides called "xtracellular eath actors" (EDFs).

A Stress-Induced Bias in the Reading of the Genetic Code in Escherichia coli.

Unlabelled: Escherichia coli mazEF is an extensively studied stress-induced toxin-antitoxin (TA) system. The toxin MazF is an endoribonuclease that cleaves RNAs at ACA sites. Thereby, under stress, the induced MazF generates a stress-induced translation machinery (STM), composed of MazF-processed mRNAs and selective ribosomes that specifically translate the processed mRNAs.

Escherichia coli Quorum-Sensing EDF, A Peptide Generated by Novel Multiple Distinct Mechanisms and Regulated by trans-Translation.

Unlabelled: Eshcerichia coli mazEF is a stress-induced toxin-antitoxin module mediating cell death and requiring a quorum-sensing (QS) extracellular death factor (EDF), the pentapeptide NNWNN. Here we uncovered several distinct molecular mechanisms involved in its generation from the zwf mRNA encoding glucose-6-phosphate dehydrogenase. In particular, we show that, under stress conditions, the endoribonuclease MazF cleaves specific ACA sites, thereby generating a leaderless zwf mRNA which is truncated 30 codons after the EDF-encoding region.

Yet another way that phage λ manipulates its Escherichia coli host: λrexB is involved in the lysogenic-lytic switch.

The life cycle of phage λ has been studied extensively. Of particular interest has been the process leading to the decision of the phage to switch from lysogenic to lytic cycle. The principal participant in this process is the λcI repressor, which is cleaved under conditions of DNA damage.

Escherichia coli antitoxin MazE as transcription factor: insights into MazE-DNA binding.

Toxin-antitoxin (TA) modules are pairs of genes essential for bacterial regulation upon environmental stresses. The mazEF module encodes the MazF toxin and its cognate MazE antitoxin. The highly dynamic MazE possesses an N-terminal DNA binding domain through which it can negatively regulate its own promoter.

The SOS response is permitted in Escherichia coli strains deficient in the expression of the mazEF pathway.

The Escherichia coli (E. coli) SOS response is the largest, most complex, and best characterized bacterial network induced by DNA damage. It is controlled by a complex network involving the RecA and LexA proteins.

Quorum sensing peptides mediating interspecies bacterial cell death as a novel class of antimicrobial agents.

mazEF is a toxin-antitoxin stress-induced module which is abundant on the chromosome of most bacteria including pathogens and most extensively studied in Escherichia coli. E. coli mazEF mediated cell death is a population phenomenon requiring the quorum-sensing (QS) 'Extracellular Death Factor' (EDF), the E.

Apoptosis-like death, an extreme SOS response in Escherichia coli.

In bacteria, SOS is a global response to DNA damage, mediated by the recA-lexA genes, resulting in cell cycle arrest, DNA repair, and mutagenesis. Previously, we reported that Escherichia coli responds to DNA damage via another recA-lexA-mediated pathway resulting in programmed cell death (PCD). We called it apoptosis-like death (ALD) because it is characterized by membrane depolarization and DNA fragmentation, which are hallmarks of eukaryotic mitochondrial apoptosis.

Novel quorum-sensing peptides mediating interspecies bacterial cell death.

ABSTRACT Escherichia coli mazEF is a toxin-antitoxin stress-induced module mediating cell death. It requires the quorum-sensing signal (QS) "extracellular death factor" (EDF), the penta-peptide NNWNN (EcEDF), enhancing the endoribonucleolytic activity of E. coli toxin MazF.

Selective translation during stress in Escherichia coli.

The bacterial stress response, a strategy to cope with environmental changes, is generally known to operate on the transcriptional level. Here, we discuss a novel paradigm for stress adaptation at the post-transcriptional level, based on the recent discovery of a stress-induced modified form of the translation machinery in Escherichia coli that is generated by MazF, the toxin component of the toxin-antitoxin (TA) module mazEF. Under stress, the induced endoribonuclease MazF removes the 3'-terminal 43 nucleotides of the 16S rRNA of ribosomes and, concomitantly, the 5'-untranslated regions (UTRs) of specific transcripts.

Two programmed cell death systems in Escherichia coli: an apoptotic-like death is inhibited by the mazEF-mediated death pathway.

In eukaryotes, the classical form of programmed cell death (PCD) is apoptosis, which has as its specific characteristics DNA fragmentation and membrane depolarization. In Escherichia coli a different PCD system has been reported. It is mediated by the toxin-antitoxin system module mazEF.

Selective translation of leaderless mRNAs by specialized ribosomes generated by MazF in Escherichia coli.

Escherichia coli (E. coli) mazEF is a stress-induced toxin-antitoxin (TA) module. The toxin MazF is an endoribonuclease that cleaves single-stranded mRNAs at ACA sequences.

The Escherichia coli extracellular death factor EDF induces the endoribonucleolytic activities of the toxins MazF and ChpBK.

Escherichia coli (E. coli) mazEF is a toxin-antitoxin (TA) stress-induced module that mediates cell death requiring the quorum-sensing pentapeptide NNWNN designated EDF (extracellular death factor). E.