Biomaterial Database

Mapping of 23-S rRNA at the ribosomal peptidyl-transferase center by photo-affinity labeling. 1977

N Sonenberg, and M Wilchek, and A Zamir

Photo-sensitive peptidyl-tRNA's were used to scan the environment of the peptidyl-transferase center of the ribosome. The specificity of the previously described labeling in the 18-S fragment of 23-S rRNA by Boc-Phe(N3)-Phe-tRNA (4-azido-N-t-butoxycarbonyl-phenylalanyl-phenylalanyl-tRNA) was demonstrated by the ability of the covalently anchored molecule to serve as donor substrate in peptide bond formation. Labeling patterns were also obtained with Boc-Phe(N3)-Phe-Phe-tRNA bound at the acceptor site and with Boc-Phe(N3)-(Gly)n-Phe-tRNA (n = 2,4). The results indicate that subsequences within the 18-S fragment of 23-S rRNA are located close to the acceptor site as well as along the path where the peptide moiety adheres to the ribosome. Identification of the labeled sequences is expected to shed light on the spatial arrangement as well as functional role of rRNA in the peptidyl transferase center.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D010458	Peptidyl Transferases	Acyltransferases that use AMINO ACYL TRNA as the amino acid donor in formation of a peptide bond. There are ribosomal and non-ribosomal peptidyltransferases.	Peptidyl Transferase,Peptidyl Translocase,Peptidyl Translocases,Peptidyltransferase,Transpeptidase,Transpeptidases,Peptidyltransferases,Transferase, Peptidyl,Transferases, Peptidyl,Translocase, Peptidyl,Translocases, Peptidyl
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D000217	Acyltransferases	Enzymes from the transferase class that catalyze the transfer of acyl groups from donor to acceptor, forming either esters or amides. (From Enzyme Nomenclature 1992) EC 2.3.	Acyltransferase
D000345	Affinity Labels	Analogs of those substrates or compounds which bind naturally at the active sites of proteins, enzymes, antibodies, steroids, or physiological receptors. These analogs form a stable covalent bond at the binding site, thereby acting as inhibitors of the proteins or steroids.	Affinity Labeling Reagents,Labeling Reagents, Affinity,Labels, Affinity,Reagents, Affinity Labeling
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D012270	Ribosomes	Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.	Ribosome
D012335	RNA, Ribosomal	The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)	Ribosomal RNA,15S RNA,RNA, 15S