Escherichia coli MazEF toxin-antitoxin system does not mediate programmed cell death.
Toxin-antitoxins systems (TAS) are prokaryotic operons containing two small overlapping genes which encode two components referred to as toxin and antitoxin. Involvement of TAS in bacterial programmed cell death (PCD) is highly controversial. MazEF, a typical type II TAS, is particularly implicated in mediating PCD in Escherichia coli. Hence, we compared the metabolic fitness and stress tolerance of E. coli strains (MC4100 and its mazEF-derivative) which were extensively used by proponents of mazEF-mediated PCD. We found that both the strains are deficient in relA gene and that the ΔmazEF strain has lower fitness and stress tolerance compared to wild type MC4100. We could not reproduce mazEF mediated PCD which emphasizes the need for skeptic approach to the PCD hypothesis.
School of Chemical and Biotechnology, SASTRA University, Thirumalaisamudram, Thanjavur, India.
Bhaskar Chandra Mohan
BC
Ramisetty
School of Chemical and Biotechnology, SASTRA University, Thirumalaisamudram, Thanjavur, India.
Swati
S
Raj
School of Chemical and Biotechnology, SASTRA University, Thirumalaisamudram, Thanjavur, India.
Dimpy
D
Ghosh
D017209:Apoptosis; D001427:Bacterial Toxins / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D004722:Endoribonucleases / Q000235:genetics* / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism*; D005798:Genes, Bacterial; D009876:Operon; D009997:Osmotic Pressure; D010641:Phenotype; D013312:Stress, Physiological
D001427:Bacterial Toxins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C422954:MazE protein, E coli; C422955:MazF protein, E coli; D004722:Endoribonucleases
Biofilm; Metabolic fitness; Toxin-antitoxin systems; mazG