Chains and heterogens:
PDB Chain Sequences:
>1cex_ (-) rttrddlingnsascadvifiyargstetgnlgtlgpsiasnlesafgkdgvwiqgvgga yratlgdnalprgtssaairemlglfqqantkcpdatliaggysqgaalaaasiedldsa irdkiagtvlfgytknlqnrgripnypadrtkvfcntgdlvctgslivaaphlaygpdar gpapefliekvravrgs