2KS6:
reference: NMR structure determination for larger proteins using backbone-only data., Raman S, Lange OF, Rossi P, Tyka M, Wang X, Aramini J, Liu G, Ramelot TA, Eletsky A, Szyperski T, Kennedy MA, Prestegard J, Montelione GT, Baker D, Science. 2010 Feb 19;327(5968):1014-8. Epub 2010 Feb 4. PMID: 20133520

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