Sequence alignment between 2q3c(A) and UniProt seq P9WP55 (CYSK_MYCTU):

P9WP55 (CYSK_MYCTU): O-acetylserine sulfhydrylase from Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv) 
                 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: MSIAEDITQLIGRTPLVRLRRVTDGAVADIVAKLEFFNPANSVKDRIGVAMLQAAEQAGLIKPDTIILEPTSGNTGIALAMVCAARGYRCVLTMPETMSLERRMLLRAYGAELILTPGADGMSGAIAKAEELAKTDQRYFVPQQFENPANPAIHRVTTAEEVWRDTDGKVDIVVAGVGTGGTITGVAQVIKERKPSARFVAVEPAASPVLSGGQKGPHPIQGIGAGFVPPVLDQDLVDEIITVGNEDALNVARRLAREEGLLVGISSGAATVAALQVARRPENAGKLIVVVLPDFGERYLSTPLFADVAD
         ...........................................X..........................................................................................................................................................................................................................................................................
PDB seq: MSIAEDITQLIGRTPLVRLRRVTDGAVADIVAKLEFFNPANSVXDRIGVAMLQAAEQAGLIKPDTIILEPTSGNTGIALAMVCAARGYRCVLTMPETMSLERRMLLRAYGAELILTPGADGMSGAIAKAEELAKTDQRYFVPQQFENPANPAIHRVTTAEEVWRDTDGKVDIVVAGVGTGGTITGVAQVIKERKPSARFVAVEPAASPVLSGGQKGPHPIQGIGAGFVPPVLDQDLVDEIITVGNEDALNVARRLAREEGLLVGISSGAATVAALQVARRPENAGKLIVVVLPDFGERYL----------
         ---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+---------+          
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