Importance of the E. coli DinJ antitoxin carboxy terminus for toxin suppression and regulated proteolysis.

摘要: Toxin-antitoxin genes play important roles in the regulation of bacterial growth during stress. One response to stress is selective proteolysis antitoxin proteins which releases their cognate toxin partners causing rapid inhibition growth. The features toxin-antitoxin complexes that are inhibit activity as well release active remain elusive. Furthermore, it unclear how antitoxins selected for by cellular proteases. Here, we test minimal structural requirements Escherichia coli DinJ suppress its partner, YafQ. We find DinJ-YafQ complex formation critically dependent on last ten C-terminal residues DinJ. However, deletion these 10 has little effect transcriptional autorepression suggesting YafQ not a critical component repression contrast other systems. further demonstrate loop 5 preceding Lon-mediated proteolysis. These results provide insights into interactions between pairs necessary and regulated antitoxins.