Ribosomal ribonucleic acid (rRNA) is a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes. Ribosomal RNA is transcribed from ribosomal DNA (rDNA) and then bound to ribosomal proteins to form small and large ribosome subunits. rRNA is the physical and mechanical factor of the ribosome that forces transfer RNA (tRNA) and messenger RNA (mRNA) to process and translate the latter into proteins. Ribosomal RNA is the predominant form of RNA found in most cells; it makes up about 80% of cellular RNA despite never being translated into proteins itself. Ribosomes are composed of approximately 60% rRNA and 40% ribosomal proteins by mass.
Pseudouridine is an isomer of the nucleoside uridine in which the uracil is attached via a carbon-carbon instead of a nitrogen-carbon glycosidic bond.
Ribonuclease III (RNase III or RNase C)(BRENDA 3.1.26.3) is a type of ribonuclease that recognizes dsRNA and cleaves it at specific targeted locations to transform them into mature RNAs. These enzymes are a group of endoribonucleases that are characterized by their ribonuclease domain, which is labelled the RNase III domain. They are ubiquitous compounds in the cell and play a major role in pathways such as RNA precursor synthesis, RNA Silencing, and the pnp autoregulatory mechanism.
The 5S ribosomal RNA is an approximately 120 nucleotide-long ribosomal RNA molecule with a mass of 40 kDa. It is a structural and functional component of the large subunit of the ribosome in all domains of life, with the exception of mitochondrial ribosomes of fungi and animals. The designation 5S refers to the molecule's sedimentation velocity in an ultracentrifuge, which is measured in Svedberg units (S).
The 23S rRNA is a 2,904 nucleotide long component of the large subunit (50S) of the bacterial/archean ribosome and makes up the peptidyl transferase center (PTC). The 23S rRNA is divided into six secondary structural domains titled I-VI, with the corresponding 5S rRNA being considered domain VII. The ribosomal peptidyl transferase activity resides in domain V of this rRNA, which is also the most common binding site for antibiotics that inhibit translation, making it a target for ribosomal engineering. A well-known member of this antibiotic class, chloramphenicol, acts by inhibiting peptide bond formation, with recent 3D-structural studies showing two different binding sites depending on the species of ribosome. Numerous mutations in domains of the 23S rRNA with Peptidyl transferase activity have resulted in antibiotic resistance. 23S rRNA genes typically have higher sequence variations, including insertions and/or deletions, compared to other rRNAs.
Helix 69 is a hairpin RNA structure containing 19 nucleotides in large subunit of the ribosome. Ribosome consists of large and small subunits joined with inter subunit bridges. Helix 69 interacts with the helix 44 (h44) of the small subunit to form the largest interface of two subunits called inter-subunit bridge B2a, one of the most conserved regions of the ribosome. Helix 69 is proposed to be a good drug target for antibacterial drugs. Many of the recent crystal structures have shown the involvement of this hairpin in different stages of the protein translation process. By targeting bacterial helix 69 specifically, protein synthesis in bacteria could be halted thus killing the bacteria.
23S rRNA (uridine2552-2'-O)-methyltransferase is an enzyme with systematic name S-adenosyl-L-methionine:23S rRNA (uridine2552-2'-O-)-methyltransferase. This enzyme catalyses the following chemical reaction
23S rRNA (adenine1618-N6)-methyltransferase (EC 2.1.1.181, rRNA large subunit methyltransferase F, YbiN protein, rlmF (gene), m6A1618 methyltransferase) is an enzyme with systematic name S-adenosyl-L-methionine:23S rRNA (adenine1618-N6)-methyltransferase. This enzyme catalyses the following chemical reaction
16S rRNA (adenine1518-N6/adenine1519-N6)-dimethyltransferase (EC 2.1.1.182, S-adenosylmethionine-6-N',N'-adenosyl (rRNA) dimethyltransferase, KsgA, ksgA methyltransferase) is an enzyme with systematic name S-adenosyl-L-methionine:16S rRNA (adenine1518-N6/adenine1519-N6)-dimethyltransferase. This enzyme catalyses the following chemical reaction
23S rRNA (uracil1939-C5)-methyltransferase (EC 2.1.1.190, RumA, RNA uridine methyltransferase A, YgcA) is an enzyme with systematic name S-adenosyl-L-methionine:23S rRNA (uracil1939-C5)-methyltransferase. This enzyme catalyses the following chemical reaction
16S rRNA pseudouridine516 synthase (EC 5.4.99.19, 16S RNA pseudouridine516 synthase, 16S PsiI516 synthase, 16S RNA Psi516 synthase, RNA pseudouridine synthase RsuA, RsuA, 16S RNA pseudouridine 516 synthase) is an enzyme with systematic name 16S rRNA-uridine516 uracil mutase. This enzyme catalyses the following chemical reaction
23S rRNA pseudouridine2457 synthase is an enzyme with systematic name 23S rRNA-uridine2457 uracil mutase. This enzyme catalyses the following chemical reaction
23S rRNA pseudouridine2604 synthase is an enzyme with systematic name 23S rRNA-uridine2604 uracil mutase. This enzyme catalyses the following chemical reaction
23S rRNA pseudouridine2605 synthase is an enzyme with systematic name 23S rRNA-uridine2605 uracil mutase. This enzyme catalyses the following chemical reaction
23S rRNA pseudouridine1911/1915/1917 synthase (EC 5.4.99.23, RluD, pseudouridine synthase RluD) is an enzyme with systematic name 23S rRNA-uridine1911/1915/1917 uracil mutase. This enzyme catalyses the following chemical reaction
tRNA pseudouridine55 synthase is an enzyme with systematic name tRNA-uridine55 uracil mutase. This enzyme catalyses the following chemical reaction
tRNA pseudouridine65 synthase is an enzyme with systematic name tRNA-uridine65 uracil mutase. This enzyme catalyses the following chemical reaction
tRNA pseudouridine13 synthase is an enzyme with systematic name tRNA-uridine13 uracil mutase. This enzyme catalyses the following chemical reaction
tRNA pseudouridine32 synthase is an enzyme with systematic name tRNA-uridine32 uracil mutase. This enzyme catalyses the following chemical reaction
23S rRNA pseudouridine746 synthase (EC 5.4.99.29, RluA, 23S RNA PSI746 synthase, 23S rRNA pseudouridine synthase, pseudouridine synthase RluA) is an enzyme with systematic name 23S rRNA-uridine746 uracil mutase. This enzyme catalyses the following chemical reaction
