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