>2nr4B (B:) observed residues (from ATOM records)
dlssfgiregiseiiastgfehpnaapigivmkgerpfvrlfkgshtwenvlkekclasn
vvydpilfvrstflvpsefeyvdagefkfpvlkeaiawvvfecinlrntslvadlvplna
gfnernikelpvpnrgfnavleatvhatryqylelirhyeslaskcggdaekkamkliye
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