Uncharacterized protein; Belongs to the YeeT/YkfH/YpjJ family.

Toxin YkfI; Toxic component of a type IV toxin-antitoxin (TA) system. Acts as a toxin inhibitor that blocks cell division and cell elongation via FtsZ and possibly also MreB (although no interaction with MreB has been proven). Overexpression results in inhibition of growth in liquid cultures and a decrease in colony formation. These effects are overcome by concomitant expression of cognate antitoxin YafW, which leads to toxin loss by an unknown mechanism. Overexpression leads to formation of lemon-shaped cells and cell lysis; inactivated by overexpression of cognate antitoxin YafW but [...]

Uncharacterized protein YfjX; Pseudogene, CP4-57 putative prophage remnant;Phage or Prophage Related; Belongs to the antirestriction protein family.

DLP12 prophage; Necessary for host cell lysis. It is believed to code for an endopeptidase that cleaves the amino-carboxyl cross-link between the diaminopimelic acid and D-alanine residues in the murein component of the bacterial cell wall (By similarity).

CP4-44 prophage; Toxic component of a type IV toxin-antitoxin (TA) system. Acts as a dual toxin inhibitor that blocks cell division and cell elongation in genetically separable interactions with FtsZ and MreB. Interacts with cytoskeletal proteins FtsZ and MreB; inhibits FtsZ GTP-dependent polymerization and GTPase activity as well as MreB ATP-dependent polymerization. Binds to both the N- and C-terminus of FtsZ, likely blocking its polymerization and localization, leading to blockage of cell division. Overexpression results in inhibition of growth in liquid cultures and decrease in col [...]

Antitoxin of the RelE-RelB toxin-antitoxin syste; Antitoxin component of a type II toxin-antitoxin (TA) system. Counteracts the effect of cognate toxin RelE via direct protein-protein interaction, preventing RelE from entering the ribosome A site and thus inhibiting its endoribonuclease activity. An autorepressor of relBE operon transcription. 2 RelB dimers bind to 2 operator sequences; DNA- binding and repression is stronger when complexed with toxin/corepressor RelE by conditional cooperativity. Increased transcription rate of relBE and activation of relE is consistent with a lower l [...]

CP4-57 prophage; Putative DNA repair protein; Belongs to the UPF0758 family.

Qin prophage; Toxic component of a type II toxin-antitoxin (TA) system. A sequence-specific, ribosome-dependent mRNA endoribonuclease that inhibits translation during amino acid starvation (the stringent response). In vitro acts by cleaving mRNA with high codon specificity in the ribosomal A site between positions 2 and 3. The stop codon UAG is cleaved at a fast rate while UAA and UGA are cleaved with intermediate and slow rates. In vitro mRNA cleavage can also occur in the ribosomal E site after peptide release from peptidyl- tRNA in the P site as well as on free 30S subunits. In vivo [...]

CP4-57 prophage; Positive regulator of the expression of the slpA gene. When overexpressed, leads to suppression of the capsule overproduction and UV sensitivity phenotypes of cells mutant for the Lon ATP-dependent protease. Part of the cryptic P4-like prophage CP4-57. Overexpression of AlpA leads to excision of the CP4-57 prophage by IntA. This inactivates ssrA (the gene upstream of the prophage) that encodes tmRNA which is required to rescue stalled ribosomes in a process known as trans- translation.