4DQV:
reference: Nonprocessive [2 + 2]e- off-loading reductase domains from mycobacterial nonribosomal peptide synthetases., Chhabra A, Haque AS, Pal RK, Goyal A, Rai R, Joshi S, Panjikar S, Pasha S, Sankaranarayanan R, Gokhale RS, Proc Natl Acad Sci U S A. 2012 Apr 10;109(15):5681-6. Epub 2012 Mar 26. PMID: 22451903

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