Tinashe Maviza, Anastasiia Zarechenskaia, Olga Dontsova, Petr Sergiev and Ilya Osterman have published a paper “RtcB2-PrfH Operon Protects E. coli ATCC25922 Strain from Colicin E3 Toxin” in International Journal of Molecular Sciences. Several bacteria harbor colicinogenic plasmids which encode toxins that impair the translational apparatus. One of them, colicin E3 ribotoxin, mediates cleavage of the 16S rRNA in the decoding center of the ribosome. A recent study demonstrated the role of PrfH and the RtcB2 module in rescuing a damaged ribosome and the subsequent re-ligation of the cleaved 16S rRNA by colicin E3 in vitro. The researchers demonstrated that the viability of E. coli ATCC25922 strain that is devoid of rtcB2 and prfH genes is impaired upon action of colicin E3, in contrast to the parental strain which has intact rtcB2 and prfH genes. Complementation of the rtcB2 and prfH gene knockout with a high copy number-plasmid encoding either rtcB2 alone or both rtcB2-prfH operon restored resistance to colicin E3. Full text of the paper is available here.