2ANI

Crystal structure of the F127Y mutant of Ribonucleotide Reductase R2 from Chlamydia trachomatis

Summary for 2ANI

• Entry DOI: 10.2210/pdb2ani/pdb
• Related: 1SYY
• Descriptor: Ribonucleoside-diphosphate reductase beta subunit, FE (III) ION, LEAD (II) ION, ... (4 entities in total)
• Functional Keywords: diiron, radical, oxidoreductase
• Biological source: Chlamydia trachomatis
• Total number of polymer chains: 1
• Total formula weight: 40898.21

Authors

Hogbom, M.,Stenmark, P.,Nordlund, P. (deposition date: 2005-08-11, release date: 2006-07-25, Last modification date: 2024-02-14)

Primary citation

Voevodskaya, N.,Galander, M.,Hogbom, M.,Stenmark, P.,McClarty, G.,Graslund, A.,Lendzian, F.
Structure of the high-valent FeIIIFeIV state in ribonucleotide reductase (RNR) of Chlamydia trachomatis--combined EPR, 57Fe-, 1H-ENDOR and X-ray studies.
Biochim.Biophys.Acta, 1774:1254-1263, 2007

PubMed Abstract: A recently discovered subgroup of class I ribonucleotide reductase (RNR) found in the infectious bacterium Chlamydia trachomatis (C. trachomatis) was shown to exhibit a high-valent Fe(III)Fe(IV) center instead of the tyrosyl radical observed normally in all class I RNRs. The X-ray structure showed that C. trachomatis WT RNR has a phenylalanine at the position of the active tyrosine in Escherichia coli RNR. In this paper the X-ray structure of variant F127Y is presented, where the tyrosine is restored. Using (1)H- and (57)Fe-ENDOR spectroscopy it is shown, that in WT and variants F127Y and Y129F of C. trachomatis RNR, the Fe(III)Fe(IV) center is virtually identical with the short-lived intermediate X observed during the iron oxygen reconstitution reaction in class I RNR from E. coli. The experimental data are consistent with a recent theoretical model for X, proposing two bridging oxo ligands and one terminal water ligand. A surprising extension of the lifetime of the Fe(III)Fe(IV) state in C. trachomatis from a few seconds to several hours at room temperature was observed under catalytic conditions in the presence of substrate. These findings suggest a possible new role for the Fe(III)Fe(IV) state also in other class I RNR, during the catalytic radical transfer reaction, by which the substrate turnover is started.

PubMed: 17827077
DOI: 10.1016/j.bbapap.2007.07.001

Experimental method

X-RAY DIFFRACTION (2 Å)