Ribonucleic acids Ribosomal

Pestka, S., Studies on transfer ribonucleic acid-ribosome complexes. Effect of antibiotics on peptidyl puromycin synthesis on polyribosomes from Escherichia coU. J. Biol. Chem. 1972, 247, 4669-4678. 

The chemical polymerization of even a moderately sized protein of a hundred amino acids in the laboratory is extremely laborious, and the yields of active product can often be low to zero (Kent and Parker, 1988). Cells accomplish this task by using an intricate mechanism which involves catalytic machinery composed of proteins, nucleic acids and their complexes, and synthesize polypeptide chains that are composed of hundreds of amino acids. This process is depicted in Fig. 2.4, and is described in the sections below. The basic components of the cellular protein synthesis apparatus, in all known biological systems, are ribosomes, which are aggregate structures containing over fifty distinct proteins, and three distinct molecules of nucleic acid known as ribosomal ribonucleic acid (ribosomal RNA or rRNA). The amino acids are brought to the ribosomes, the assembly bench , by an RNA molecule known appropriately as transfer RNA . Each of the twenty amino acids is specifically coupled to a set of transfer RNAs (discussed below) which catalyze their incorporation into appropriate locations in the linear sequence of polypeptide chains. Several other intracellular proteins known as init iation and elongation factors a re also required for protein synthesis. 

See also genetic code messenger RNA oligonucleotide RIBONUCLEIC ACID RIBOSOMAL RNA. 

Pestka S. Studies on the formation of transfer ribonucleic acid-ribosome complexes. VIH. Survey of the effect of antibiotics on N-acetyl-phenylalanyl-puromycin formation Possible mechanism of chloramphenicol action. Atch Biochem Biophys 1970 136 80-88. 

Ofengand, J., Henes, C. The function of pseudouridylic acid in transfer ribonucleic acid II. Inhibition of amino acyl transfer ribonucleic acid-ribosome complex formation by ribothymidylylpseudouridylyl-cytidylyl-guanosine 3 -phosphate, J. biol. Chem. 244, 6241-6253 (1969)... 

McKeehan, W. L., 1974, Regulation of hemoglobin synthesis Effect of concentration of messenger ribonucleic acid, ribosome subunits, initiation factors, and salts on ratio of a and p chains synthesized in vitro, J. Biol. Chem. 249 6517. 

Cellular protein biosynthesis involves the following steps. One strand of double-stranded DNA serves as a template strand for the synthesis of a complementary single-stranded messenger ribonucleic acid (mRNA) in a process called transcription. This mRNA in turn serves as a template to direct the synthesis of the protein in a process called translation. The codons of the mRNA are read sequentially by transfer RNA (tRNA) molecules, which bind specifically to the mRNA via triplets of nucleotides that are complementary to the particular codon, called an anticodon. Protein synthesis occurs on a ribosome, a complex consisting of more than 50 different proteins and several stmctural RNA molecules, which moves along the mRNA and mediates the binding of the tRNA molecules and the formation of the nascent peptide chain. The tRNA molecule carries an activated form of the specific amino acid to the ribosome where it is added to the end of the growing peptide chain. There is at least one tRNA for each amino acid. 

Ribonucleic acid (RNA) Molecules including messenger RNA, transfer RNA, ribosomal RNA, or small RNA. RNA serves as a template for protein synthesis and other biochemical processes of the cell. The structure of RNA is similar to that of DNA except for the base thymidine being replaced by uracil. 

Draper, P.E., and Gold, L. (1980) A method for linking fluorescent labels to polynucleotides Application to studies of ribosome-ribonucleic acid interactions. Biochemistry 19, 1774-1781. 

Odom Jr., O.W., Robins, D.J., Lynch, J., Dottavio-Martin, D., Kramer, G., and Hardesty, B. (1980) Distances between 3 ends of ribosomal ribonucleic acids reassembled into Escherichia coli ribosomes. 

Politz, S.M., Noller, H.F., and McWhirter, P.D. (1981) Ribonucleic acid-protein cross-linking in Escherichia coli ribosomes (4-azidophenyl) glyoxal, a novel heterobifunctional reagent. Biochemistry 20, 372-378. 

The initial conversion of light into chemical energy takes place in the thylakoid membrane. Besides the chlorophylls and series of electron carriers, the thylakoid membrane also contains the enzyme adenosine triphosphate (ATP) synthase. The enzymes that are responsible for the actual fixation of C02 and the synthesis of carbohydrate reside in the stroma that surround the thylakoid membrane. The stroma also contains deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and ribosomes that are essential for protein synthesis [37]. 

Ribosomal synthesis of peptides proceeds through translation of messenger ribonucleic acid (mRNA) and utilizes the 20 primary L-a-amino acids. These amino acids are incorporated with the use of specific transfer ribonucleic acid (tRNA) codons. The 20 primary a-amino acids, with the exception of glycine that is achiral, are characterized by an L-configuration at the a-position (Figure 1). In general, most proteins are found to be composed of these 20 L-a-amino acids, as such they are referred to as protein amino acids. 

Unlike the organelles described above, ribosomes have no membrane but are aggregates of ribonucleic acid (RNA) and protein. Each ribosome consists of two subunits a large and a smaller one (Figure 1.7). 

NAD Oxidized nicotinamide adenine rRNA Ribosomal ribonucleic acid... 

Wilkinson DS, Pitot HC. Inhibition of ribosomal ribonucleic acid maturation in Novikoff hepatoma cells by 5-fluorouracil and 5-fluorouridine. J Biol Chem 1973 248 63-68. 

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