1GAM:
reference: The X-ray structures of two mutant crystallin domains shed light on the evolution of multi-domain proteins., Norledge BV, Mayr EM, Glockshuber R, Bateman OA, Slingsby C, Jaenicke R, Driessen HP, Nat Struct Biol 1996 Mar;3(3):267-74. PMID: 8605629

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