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PubMed · 3290201

Colicin E8, a DNase which indicates an evolutionary relationship between colicins E2 and E3.

M Toba·H Masaki·T Ohta
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Abstract

Colicin E8-J and its immunity protein were characterized with regard to their activities and gene structures. Colicin E8 is a complex of proteins A and B; protein A (the naked E8) exhibits an apparently nonspecific DNase activity that is inhibited by protein B (the immunity protein), as in the case of colicin E2. The nucleotide sequence of the downstream half of the colicin operon of ColE8-J was determined to be highly homologous to that of ColE2-P9, with the exception of the hot spot region of the 3'-terminal segment of the colicin gene and the adjacent immunity gene. The immE2-like gene of ColE3-CA38 was, as assumed previously, extensively homologous to the immE8 gene of ColE8-J, and thus, ColE8-J was shown to be situated between ColE2-P9 and ColE3-CA38 in the evolution of the E-group Col plasmids.

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Amino Acid SequenceBacterial ProteinsBacteriocin PlasmidsBase SequenceBiological EvolutionColicinsDNA, BacterialDeoxyribonucleasesEscherichia coliEscherichia coli ProteinsGenes, BacterialMolecular Sequence DataOperonPlasmidsSequence Homology, Nucleic AcidJournal ArticleResearch Support, Non-U.S. Gov't

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M Toba, H Masaki, T Ohta. 1988. Colicin E8, a DNase which indicates an evolutionary relationship between colicins E2 and E3.. https://doi.org/10.1128/jb.170.7.3237-3242.1988

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