Sequence alignment between 5v2c(I) and UniProt seq P12240 (PSBI_THEVL):

P12240 (PSBI_THEVL): Photosystem II reaction center protein I from Thermostichus vulcanus 
                 10        20        30        
         ---------+---------+---------+--------
UniProt: METLKITVYIVVTFFVLLFVFGFLSGDPARNPKRKDLE
         X.....................................
PDB seq: XETLKITVYIVVTFFVLLFVFGFLSGDPARNPKRKDLE
         ---------+---------+---------+--------
                 10        20        30