Chains and heterogens:
PDB Chain Sequences:
>1xupO (O:) yvmaidqgttssraiifdrngkkigssqkefpqyfpksgwvehnaneiwnsvqsviagaf iesgirpeaiagigitnqrettvvwdkttgqpianaivwqsrqsspiadqlkvdghtemi hektglvidayfsatkvrwlldniegaqekadngellfgtidswlvwkltdgqvhvtdys nasrtmlynihklewdqeildllnipssmlpevksnsevyghtrsyhfygsevpiagmag dqqaalfgqmafekgmikntygtgafivmntgeepqlsdndllttigygingkvyyaleg sifvagsaiqwlrdglrmietspqseelaakakgdnevyvvpaftglgapywdseargav fgltrgttkedfvratlqavayqskdvidtmkkdsgidipllkvdggaakndllmqfqad ildidvqraanlettalgaaylaglavgfwkdldelksmaeegqmftpempaeerdnlye gwkqava
>1xupX (X:) yvmaidqgttssraiifdrngkkigssqkefpqyfpksgwvehnaneiwnsvqsviagaf iesgirpeaiagigitnqrettvvwdkttgqpianaivwqsrqsspiadqlkvdghtemi hektglvidayfsatkvrwlldniegaqekadngellfgtidswlvwkltdgqvhvtdys nasrtmlynihklewdqeildllnipssmlpevksnsevyghtrsyhfygsevpiagmag dqqaalfgqmafekgmikntygtgafivmntgeepqlsdndllttigygingkvyyaleg sifvagsaiqwlrdglrmietspqseelaakakgdnevyvvpaftglgapywdseargav fgltrgttkedfvratlqavayqskdvidtmkkdsgidipllkvdggaakndllmqfqad ildidvqraanlettalgaaylaglavgfwkdldelksmaeegqmftpempaeerdnlye gwkqava