>4u19B (B:) observed residues (from ATOM records)
mgfetlvvtsedgitkimfnrpkkknaintemyheimralkaaskddsiitvltgngdyy
ssgndltnppggveekaknnavllrefvgcfidfpkpliavvngpavgisvtllglfdav
yasdratfhtpfshlgqspegcssytfpkimspakatemlifgkkltageacaqglvtev
fpdstfqkevwtrlkafaklppnalriskevirkrereklhavnaeecnvlqgrwlsdec
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