A repressor that monitors the supply of DNA building blocks

Ribonucleotide reductase (RNR) is an essential enzyme that catalyzes the synthesis of DNA building blocks. In a new study from Britt-Marie Sjöberg’s and Pål Stenmark’s groups at DBB, they present several cryo-EM structures and the mechanism of action of NrdR. NrdR is the RNR-specific repressor, that controls transcription of RNR genes in bacteria. The repressor uses an unprecedented nucleotide-sensing oligomerization mechanism to control NrdR-dependent transcription of ribonucleotide reductases.