Ribonucleotide reductases: radical enzymes with suicidal tendencies.
نویسندگان
چکیده
Ribonucleotide reductases catalyze a key step in DNA biosynthesis, using a diverse array of unprecedented metallo-cofactors to generate a transient protein radical that initiates nucleotide reduction. The new understanding of the chemistry and biochemistry of the system has allowed rational design of inhibitors of this process, which function as antitumor and antiviral agents.
منابع مشابه
A dityrosyl-diiron radical cofactor center is essential for human ribonucleotide reductases.
Ribonucleotide reductase catalyzes the reduction of ribonucleotides to deoxyribonucleotides for DNA biosynthesis. A tyrosine residue in the small subunit of class I ribonucleotide reductase harbors a stable radical, which plays a central role in the catalysis process. We have discovered that an additional tyrosine residue, conserved in human small subunits hRRM2 and p53R2, is required for the r...
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Ribonucleotide reductases (RNRs) catalyze the production of deoxyribonucleotides, which are essential for DNA synthesis and repair in all organisms. The three currently known classes of RNRs are postulated to utilize a similar mechanism for ribonucleotide reduction via a transient thiyl radical, but they differ in the way this radical is generated. Class I RNR, found in all eukaryotic organisms...
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ورودعنوان ژورنال:
- Chemistry & biology
دوره 2 12 شماره
صفحات -
تاریخ انتشار 1993