4U5P: Crystal Structure Of Native Rhcc (yp_702633.1) From Rhodococcus Jostii Rha1 At 1.78 Angstrom

The vast majority of characterized oxygenases use bound cofactors to activate molecular oxygen to carry out oxidation chemistry. Here, we show that an enzyme of unknown activity, RhCC from Rhodococcus jostii RHA1, functions as an oxygenase, using 4-hydroxyphenylenolpyruvate as a substrate. This unique and complex reaction yields 3-hydroxy-3-(4-hydroxyphenyl)-pyruvate, 4-hydroxybenzaldehyde, and oxalic acid as major products. Incubations with H2(18)O, (18)O2, and a substrate analogue suggest that this enzymatic oxygenation reaction likely involves a peroxide anion intermediate. Analysis of sequence similarity and the crystal structure of RhCC (solved at 1.78 A resolution) reveal that this enzyme belongs to the tautomerase superfamily. Members of this superfamily typically catalyze tautomerization, dehalogenation, or decarboxylation reactions rather than oxygenation reactions. The structure shows the absence of cofactors, establishing RhCC as a rare example of a redox-metal- and coenzyme-free oxygenase. This sets the stage to study the mechanistic details of cofactor-independent oxygen activation in the unusual context of the tautomerase superfamily.
PDB ID: 4U5PDownload
MMDB ID: 127299
PDB Deposition Date: 2014/7/25
Updated in MMDB: 2015/02
Experimental Method:
x-ray diffraction
Resolution: 1.78  Å
Source Organism:
Similar Structures:
Biological Unit for 4U5P: trimeric; determined by author and by software (PISA)
Molecular Components in 4U5P
Label Count Molecule
Proteins (3 molecules)
Molecule annotation
Chemicals (5 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB