Sequence alignment between 1psf(A) and UniProt seq P31969 (PSAE_SYNP2):

P31969 (PSAE_SYNP2): Photosystem I reaction center subunit IV from Picosynechococcus sp. (strain ATCC 27264 / PCC 7002 / PR-6) 
                 10        20        30        40        50        60        70
         ---------+---------+---------+---------+---------+---------+---------+
UniProt: MAIERGSKVKILRKESYWYGDVGTVASIDKSGIIYPVIVRFNKVNYNGFSGSAGGLNTNNFAEHELEVVG
PDB seq: -AIERGSKVKILRKESYWYGDVGTVASIDKSGIIYPVIVRFNKVNYNGFSGSAGGLNTNNFAEHELEVVG
          ---------+---------+---------+---------+---------+---------+---------
                  10        20        30        40        50        60