2E4L:
reference: Structural, thermodynamic, and mutational analyses of a psychrotrophic RNase HI., Tadokoro T, You DJ, Abe Y, Chon H, Matsumura H, Koga Y, Takano K, Kanaya S, Biochemistry. 2007 Jun 26;46(25):7460-8. Epub 2007 May 31. PMID: 17536836

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