Sequence alignment between 3iqh(X) and UniProt seq P45040 (CYSK_HAEIN):

P45040 (CYSK_HAEIN): Cysteine synthase from Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd)
                 10        20        30        40        50        60        70        80        90       100       110       120       130       140       150       160       170       180       190       200       210       220       230       240       250       260       270       280       290       300       310      
         ---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+------
UniProt: MAIYADNSYSIGNTPLVRLKHFGHNGNVVVKIEGRNPSYSVKCRIGANMVWQAEKDGTLTKGKEIVDATSGNTGIALAYVAAARGYKITLTMPETMSLERKRLLCGLGVNLVLTEGAKGMKGAIAKAEEIVASDPSRYVMLKQFENPANPQIHRETTGPEIWKDTDGKVDVVVAGVGTGGSITGISRAIKLDFGKQITSVAVEPVESPVISQTLAGEEVKPGPHKIQGIGAGFIPKNLDLSIIDRVETVDSDTALATARRLMAEEGILAGISSGAAVAAADRLAKLPEFADKLIVVILPSASERYLSTALFEGIEG
         .........................................X..................................................................................................................................................................................................................................................................................
PDB seq: -AIYADNSYSIGNTPLVRLKHFGHNGNVVVKIEGRNPSYSVXCRIGANMVWQAEKDGTLTKGKEIVDATSGNTGIALAYVAAARGYKITLTMPETMSLERKRLLCGLGVNLVLTEGAKGMKGAIAKAEEIVASDPSRYVMLKQFENPANPQIHRETTGPEIWKDTDGKVDVVVAGVGTGGSITGISRAIKLDFGKQITSVAVEPVESPVISQTLAGEEVKPGPHKIQGIGAGFIPKNLDLSIIDRVETVDSDTALATARRLMAEEGILAGISSGAAVAAADRLAKLPEFADKLIVVILPSASERYLSTALF-----
          --------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+-     
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