DNA-directed RNA polymerase subunit beta (bacterial) (RNAP β)

The DNA-directed RNA polymerase subunit beta is a core catalytic subunit of the bacterial DNA-dependent RNA polymerase (RNAP), responsible for RNA synthesis from a DNA template[2][4][5]. Encoded by the rpoB gene, the β subunit forms part of the enzymatic center, directly contributing to the catalysis of ribonucleotide polymerization and binding of nucleic acids[2][5][7]. The β subunit is integral to the core enzyme's structure, associating with β', two α subunits, and ω to form the RNAP core, which associates with sigma factors for promoter recognition[4][2][5]. The β subunit is the main binding site for rifampin and other antibiotics, making it a critical drug target in antimicrobial therapy[3][4]. Mutations in the β subunit confer resistance to rifampin, an important consideration in the treatment of tuberculosis and other bacterial infections[2][4].

Other names

RNA polymerase beta subunitRNAP β subunitrpoB gene productBacterial RNA polymerase β

Inhibition of RNA synthesis by binding β subunit and blocking the transcription initiation or elongation process (e.g., rifampin binds β subunit to inhibit RNA chain elongation) - Allosteric inhibition of transcription initiation or elongation (drug-dependent)