Sequence alignment between 3a0b(M) and UniProt seq P12312 (PSBM_THEVL):

P12312 (PSBM_THEVL): Photosystem II reaction center protein M from Thermostichus vulcanus 
                 10        20        30      
         ---------+---------+---------+------
UniProt: MEVNQLGFIATALFVLVPSVFLIILYVQTESQQKSS
PDB seq: MEVNQLGFIATALFVLVPSVFLIILYVQTESQQKSS
         ---------+---------+---------+------
                 10        20        30