Summary: Ribosomal protein S12/S23
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Ribosomal protein S12/S23 Provide feedback
This protein is known as S12 in bacteria and archaea and S23 in eukaryotes.
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR006032
Ribosomes are the particles that catalyse mRNA-directed protein synthesis in all organisms. The codons of the mRNA are exposed on the ribosome to allow tRNA binding. This leads to the incorporation of amino acids into the growing polypeptide chain in accordance with the genetic information. Incoming amino acid monomers enter the ribosomal A site in the form of aminoacyl-tRNAs complexed with elongation factor Tu (EF-Tu) and GTP. The growing polypeptide chain, situated in the P site as peptidyl-tRNA, is then transferred to aminoacyl-tRNA and the new peptidyl-tRNA, extended by one residue, is translocated to the P site with the aid the elongation factor G (EF-G) and GTP as the deacylated tRNA is released from the ribosome through one or more exit sites [PUBMED:11297922, PUBMED:11290319]. About 2/3 of the mass of the ribosome consists of RNA and 1/3 of protein. The proteins are named in accordance with the subunit of the ribosome which they belong to - the small (S1 to S31) and the large (L1 to L44). Usually they decorate the rRNA cores of the subunits.
Many ribosomal proteins, particularly those of the large subunit, are composed of a globular, surfaced-exposed domain with long finger-like projections that extend into the rRNA core to stabilise its structure. Most of the proteins interact with multiple RNA elements, often from different domains. In the large subunit, about 1/3 of the 23S rRNA nucleotides are at least in van der Waal's contact with protein, and L22 interacts with all six domains of the 23S rRNA. Proteins S4 and S7, which initiate assembly of the 16S rRNA, are located at junctions of five and four RNA helices, respectively. In this way proteins serve to organise and stabilise the rRNA tertiary structure. While the crucial activities of decoding and peptide transfer are RNA based, proteins play an active role in functions that may have evolved to streamline the process of protein synthesis. In addition to their function in the ribosome, many ribosomal proteins have some function 'outside' the ribosome [PUBMED:11290319, PUBMED:11114498].
Ribosomal protein S12 is one of the proteins from the small ribosomal subunit. In Escherichia coli, S12 is known to be involved in the translation initiation step. It is a very basic protein of 120 to 150 amino-acid residues. S12 belongs to a family of ribosomal proteins which are grouped on the basis of sequence similarities. This protein is known typically as S12 in bacteria, S23 in eukaryotes and as either S12 or S23 in the Archaea.
Bacterial S12 molecules contain a conserved aspartic acid residue which undergoes a novel post-translational modification, beta-methylthiolation, to form the corresponding 3-methylthioaspartic acid.
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Cellular component||ribosome (GO:0005840)|
|Molecular function||structural constituent of ribosome (GO:0003735)|
|Biological process||translation (GO:0006412)|
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The OB (oligonucleotide/oligosaccharide binding) was defined by Murzin . The common part of the OB-fold, has a five-stranded beta-sheet coiled to form a closed beta-barrel. This barrel is capped by an alpha-helix located between the third and fourth strands .
The clan contains the following 58 members:BOF BRCA-2_OB1 BRCA-2_OB3 CSD DNA_ligase_A_C DNA_ligase_OB DNA_ligase_OB_2 DUF2110 DUF223 DUF3127 EFP eIF-1a eIF-5a Elong-fact-P_C EutN_CcmL EXOSC1 mRNA_cap_C NlpE_C OB_aCoA_assoc OB_NTP_bind OB_RNB PCB_OB Phage_DNA_bind POT1 RecG_wedge RecO_N RecO_N_2 Rep-A_N Rep_fac-A_3 Rep_fac-A_C REPA_OB_2 Rho_RNA_bind Ribosom_S12_S23 Ribosomal_L2 Ribosomal_S17 Ribosomal_S28e RNA_pol_Rbc25 RNA_pol_Rpb8 RNA_pol_RpbG RsgA_N RuvA_N S1 S1-like S1_2 SSB SSL_OB Stn1 TEBP_beta Ten1 Ten1_2 TOBE TOBE_2 TOBE_3 TRAM tRNA_anti-codon tRNA_anti-like tRNA_anti_2 tRNA_bind
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Curation and family details
|Previous IDs:||S12; Ribosomal_S12;|
|Number in seed:||12|
|Number in full:||2721|
|Average length of the domain:||122.70 aa|
|Average identity of full alignment:||50 %|
|Average coverage of the sequence by the domain:||88.10 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 11927849 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||22|
|Download:||download the raw HMM for this family|
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There are 22 interactions for this family. More...
We determine these interactions using iPfam, which considers the interactions between residues in three-dimensional protein structures and maps those interactions back to Pfam families. You can find more information about the iPfam algorithm in the journal article that accompanies the website.
For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Ribosom_S12_S23 domain has been found. There are 517 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.
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