2R0G: Chromopyrrolic Acid-Soaked Rebc With Bound 7-Carboxy-K252c

The biosynthesis of rebeccamycin, an antitumor compound, involves the remarkable eight-electron oxidation of chlorinated chromopyrrolic acid. Although one rebeccamycin biosynthetic enzyme is capable of generating low levels of the eight-electron oxidation product on its own, a second protein, RebC, is required to accelerate product formation and eliminate side reactions. However, the mode of action of RebC was largely unknown. Using crystallography, we have determined a likely function for RebC as a flavin hydroxylase, captured two snapshots of its dynamic catalytic cycle, and trapped a reactive molecule, a putative substrate, in its binding pocket. These studies strongly suggest that the role of RebC is to sequester a reactive intermediate produced by its partner protein and to react with it enzymatically, preventing its conversion to a suite of degradation products that includes, at low levels, the desired product.
PDB ID: 2R0GDownload
MMDB ID: 59597
PDB Deposition Date: 2007/8/19
Updated in MMDB: 2012/11
Experimental Method:
x-ray diffraction
Resolution: 2.37  Å
Source Organism:
Similar Structures:
Biological Unit for 2R0G: monomeric; determined by author and by software (PISA)
Molecular Components in 2R0G
Label Count Molecule
Protein (1 molecule)
Molecule annotation
Chemicals (2 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB