Chains and heterogens:
PDB Chain Sequences:
>1xuk_ (-) ivggytcgantvpyqvslnsgyhfcggslinsqwvvsaahcyksgiqvrlgedninvveg neqfisasksivhpsynsntlnndimliklksaaslnsrvasislptscasagtqclisg wgntkssgtsypdvlkclkapilsdsscksaypgqitsnmfcagyleggkdscqgdsggp vvcsgklqgivswgsgcaqknkpgvytkvcnyvswikqtiasn