>1bt1A (A:) observed residues (from ATOM records)
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akfakavelmkalpaddprnfyqqalvhcaycnggydqvnfpdqeiqvhnswlffpfhrw
ylyfyerilgkligdpsfglpfwnwdnpggmvlpdflndstsslydsnrnqshlppvvvd
lgyngadtdvtdqqritdnlalmykqmvtnagtaelflgkayragdapspgagsietsph
ipihrwvgdprntnnedmgnfysagrdiafychhsnvdrmwtiwqqlardytdsdwlnat
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