>TIGR00982 S23_S12_E_A ribosomal protein S23 (S12); InterPro: IPR005680 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 , . 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 of 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 , . 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 family represents the eukaryotic and archaeal homologs of bacterial ribosomal protein S12. This protein is known typically as S23 in eukaryotes and as either S12 or S23 in the Archaea.; GO: 0003735 structural constituent of ribosome, 0006412 translation, 0015935 small ribosomal subunit.

Probab=99.91  E-value=7.8e-25  Score=166.44  Aligned_cols=102  Identities=40%  Similarity=0.692  Sum_probs=86.5

Q ss_pred             CCCCCCCCCCCCCCCCCCCEEEEEEEECCCCCCCCCCCEEEEEEE-CCCCEEEEEECCCC--CCCCCCCEEEEEC--CC-
Q ss_conf             786466667700068621247875675184567442432889996-69969999807888--7546467899953--78-
Q gi|254780266|r   14 GSFRACAKVTALRGNPQKRGVCLRVYTVTPKKPNSALRKVIKARL-TSGVEVIAYVPGEG--HNLQEHSVVMLCG--GR-   87 (124)
Q Consensus        14 k~~~~~~K~~~L~~~PqkkGVclkv~~~~PKKPNSA~RKvarV~L-sng~~v~ayIPGeG--hnlqehs~VLvrG--Gr-   87 (124)
T Consensus        25 r~l~l~~k~dPleGaP~arGivlek~~~ea~qPns~~rk~vrvql~kn~~~~taf~P~dG~i~f~dehdev~~e~iGG~~  104 (139)
T TIGR00982        25 RVLRLKEKADPLEGAPQARGIVLEKVGVEAKQPNSALRKAVRVQLIKNGKVVTAFVPGDGAINFIDEHDEVIVEGIGGPK  104 (139)
T ss_pred             HHHHHHHCCCCCCCCCCCCCEEEEEEEEECCCCCHHHHHEEEEEEEECCCEEEEEECCCCCEEEEECCCEEEEECCCCCC
T ss_conf             43222110576467855352576532210128602331112245652573688870689834454246607884357888


Q ss_pred             ---CCCCCCCEEEEEE--CCCCCCCCCCCCCCC
Q ss_conf             ---3888875478980--400144334200121
Q gi|254780266|r   88 ---VKDLPGVKYRVIR--GVLDAQGVKNRKQAR  115 (124)
Q Consensus        88 ---v~DlPGVry~ivR--G~~D~~gv~~Rk~~R  115 (124)
T Consensus       105 G~smGdiPGvry~v~~vn~~sl~~l~~G~~~k~  137 (139)
T TIGR00982       105 GRSMGDIPGVRYKVVKVNNVSLKELVKGKKEKP  137 (139)
T ss_pred             CCCCCCCCCCEEEEEEECHHHHHHHHHHHHHCC
T ss_conf             873346786037988751036888862232125