Download MendeleyThe radical site in chlamydial ribonucleotide reductase defines a new R2 subclass.
Hogbom, M., Stenmark, P., Voevodskaya, N., McClarty, G., Graslund, A., Nordlund, P.(2004) Science 305: 245-248
- PubMed: 15247479
- DOI: https://doi.org/10.1126/science.1098419
- Primary Citation of Related Structures:
1SYY - PubMed Abstract:
Ribonucleotide reductase (RNR) synthesizes the deoxyribonucleotides for DNA synthesis. The R2 protein of normal class I ribonucleotide reductases contains a diiron site that produces a stable tyrosyl free radical, essential for enzymatic activity. Structural and electron paramagnetic resonance studies of R2 from Chlamydia trachomatis reveal a protein lacking a tyrosyl radical site. Instead, the protein yields an iron-coupled radical upon reconstitution. The coordinating structure of the diiron site is similar to that of diiron oxidases/monoxygenases and supports a role for this radical in the RNR mechanism. The specific ligand pattern in the C. trachomatis R2 metal site characterizes a new group of R2 proteins that so far has been found in eight organisms, three of which are human pathogens.
Organizational Affiliation:
Department of Biochemistry and Biophysics, Stockholm University, Roslagstullsbacken 15, Albanova University Center, SE-10691 Stockholm, Sweden.
