Chains and heterogens:
PDB Chain Sequences:
>1xas_ (-) aestlgaaaaqsgryfgtaiasgrlsdstytsiagrefnmvtaenemkidatepqrgqfn fssadrvynwavqngkqvrghtlawhsqqpgwmqslsgrplrqamidhingvmahykgki vqwdvvneafadgssgarrdsnlqrsgndwievafrtaraadpsaklcyndynvenwtwa ktqamynmvrdfkqrgvpidcvgfqshfnsgspynsnfrttlqnfaalgvdvaiteldiq gapastyanvtndclavsrclgitvwgvrdsdswrseqtpllfnndgskkaaytavlda
>1xas_ (-) lgaaaaqsgryfgtaiasgrlsdstytsiagrefnmvtaenemkidatepqrgqfnfssa drvynwavqngkqvrghtlawhsqqpgwmqslsgrplrqamidhingvmahykgkivqwd vvneafadgssgarrdsnlqrsgndwievafrtaraadpsaklcyndynvenwtwaktqa mynmvrdfkqrgvpidcvgfqshfnsgspynsnfrttlqnfaalgvdvaiteldiqgapa styanvtndclavsrclgitvwgvrdsdswrseqtpllfnndgskkaaytavlda