3STQ:
reference: Crystal structure of Pseudomonas aeruginosa Tsi2 reveals a stably folded superhelical antitoxin., Zou T, Yao X, Qin B, Zhang M, Cai L, Shang W, Svergun DI, Wang M, Cui S, Jin Q, J Mol Biol. 2012 Apr 6;417(4):351-61. Epub 2012 Jan 30. PMID: 22310046

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