The metY-rimP-nusA-infB-rfbA-truB-rpsO-pnp operon in E. coli contains eight genes involved in the 30S ribosome subunit formation, as well as transcription, translation and tRNA formation. The operon can be activated by DNA-binding protein Fis, which binds to the promoter region and activates transcription of the operon. The operon can also be inactivated by either cAMP-activated global transcriptional regulator CRP or an arginine repressor. When cAMP binds to CRP, it activates it, allowing it to bind to the promoter region, preventing transcription of the operon. Similarly, L-arginine can form a complex with six subunits of the ArgR protein, forming an arginine repressor that binds to and inhibits the transcription of the operon. This operon also has multiple terminators, and if they are formed under certain conditions, can prevent the rest of the operon from being transcribed. The first gene in the operon, metY, encodes a tRNA molecule with the anticodon CAU, which corresponds to the amino acid methionine. The second gene, rimP, encodes the ribosome maturation factor RimP, which is involved in the maturation of the 30S ribosomal subunit. The third gene, nusA, encodes the transcription termination/antitermination protein NusA, which is involved in the termination and antitermination of transcription, as well as having a role in response to DNA damage. The fourth gene, infB, encodes the translation initiation factor IF-2, which is a protein essential for the initiation of protein synthesis, as it ensures the proper binding of N-Formomethionine (fMet), a methionine molecule with a formyl group added to its amino group which is necessary for the initiation of protein synthesis in bacteria. The fifth gene, rbfA, encodes a 30S ribosome-binding factor which is involved in the maturation of the ribosomal 30S subunit. The sixth gene, truB, encodes tRNA pseudouridine synthase B, which synthesizes pseudouridine, which is present in tRNA of E. coli, and allows it to be more thermally stable. The seventh gene, rpsO, encodes the 30S ribosomal protein S15, a protein that makes up the ribosomal 30S subunit, and it directly binds to the 16S rRNA, another component of the 30S subunit and a region widely studied in bacteria. The final gene in the operon, pnp, encodes polyribonucleutode nucleotidyltransferase, an enzyme that degrades mRNA, and is also involved in the maturation and degradation of tRNA.

Operon: Ribosomal Protein rpsO References