Sequence alignment between 9is4(F) and UniProt seq Q08363 (PSBF_CHLRE):

Q08363 (PSBF_CHLRE): Cytochrome b559 subunit beta from Chlamydomonas reinhardtii 
                 10        20        30        40    
         ---------+---------+---------+---------+----
UniProt: MTTKKSAEVLVYPIFTVRWLAIHGIAVPTIFFLGAITAMQFIQR
PDB seq: -------------IFTVRWLAIHGIAVPTIFFLGAITAMQFIQR
                      ------+---------+---------+----
                           20        30        40