Protein
Dichlorochromopyrrolate synthase
Organism
Lechevalieria aerocolonigenes
Function
Involved in the biosynthesis of the indolocarbazole antitumor agent rebeccamycin. Catalyzes the hydrogen peroxide-dependent dimerization of two L-tryptophan-derived molecules (imine form of indole 3-pyruvate (IPA)), to form dichlorochromopyrrolic acid (CPA), the precursor for the six-ring bisindolopyrrolocarbazole scaffold of the rebeccamycin. The hydrogen peroxide is provided together with iminoindolpropanoate by RebO. Due to the instability of indole 3-pyruvate (IPA), which is hydrolyzed in solution and exits in equilibrium with the predominant ketone form of IPA, the concerted functioning of the RebO/RebD system appears to prevent the buildup of significant amounts of IPA and its imine in solution, effectively shepherding the imine further down the biosynthetic chain.
Similarity
Belongs to the RebD family.
Sequence
MSVFDLPRLHFAGTATTRLPTGPRNGLVDLSTHSVVMDGERFPASRPAAEYHAYLDRVGGKGTAFAGNGYFAIDAGITAVERAAGEVDTGDLLVGRAVDVWGHYNEYLATTFNRARIFDVDPSSSWTSTVMIGQFGFGRLGRSHDVGYVFTGGVHGMQPPRWHEDGRVLHQFTVPAGEDMTWFGSAADSPAAARLRELVESGEADGLVVQLALSDAGPAPMPHAQQWRLRGTIAPWHAGEPRTCPAGRLLTPHNLTADLRGDHVSLNLISFRPPTGISGLELRTADTDRFIARVPADDPHGVVTVPAAEGGDEALCVVGTTAAGERIVVSREREVTVHVDDASVFLEHPRGPGDSDQDAEIAVRTYVRGEPAAATIHIGQYFNPRAFPLDEHATAASATPEDLDVVALCVDGTRWSRHCVISTDENGDGRFLLRGARPGATRLLLSAEGATPFDGLTAAAAYDNDDSLGLWSGLASVAVRVLPDHWWMDDIPRDKVTFDLLYREVFAFYELLYSFMGEEVFSLADRFRVETHPRLIWQMCDPRNRAKTYYMPPTRDLTGPQARLLLAYLRAQNSDVVVPVIEPSHTRSGTPISTRTDLVRALRHGVAIELAVMLQYLYAAFSIPTHGAGQELVSRGDWTPEQLRLMCGDGGETTDGGVRGSLLGVAREEMIHFLVVNNVLMAVGEPFHVPDLDFGTINDTLMVPLDFSLEALGLGSVQRFIQIEQPEGLTGAVRLGDLPVPVREAEDFHYASLSELYGDIREGLQRVPGLFLVERGRGGGEHHLFLRESVNAVHPDYQLEVDDLSSALFAIDFVTEQGEGHVLTDEDTGEESHYDTFVRVADLLMKERLTAADTRRAQWSPAYPVARNPTVHGGGQSKELVTSPVARELMVLFNKSYFMMLQLMVQHFGGSPDASLRRSKLMNAAIDVMTGVMRPLAELLVTVPSGRHGRTAGPSFELDEKPAFIPRADVARRAISLRFRHLAESARTCALVPDKVVRNLDFLADQFATEGPR