>1bt2B (B:) observed residues (from ATOM records)
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ylyfyerilgkligdpsfglpfwnwdnpggmvlpdflndstsslydsnrnqshlppvvvd
lgyngadtdvtdqqritdnlalmykqmvtnagtaelflgkayragdapspgagsietsph
ipihrwvgdprntnnedmgnfysagrdiafychhsnvdrmwtiwqqlardytdsdwlnat
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