Transfer ribonucleic acid structure

Potts, R.O., Ford, Jr., N.C. and Fournier, M.J. (1981) Changes in the solution structure of yeast phenylalanine transfer ribonucleic acid associated with aminoacylation and magnesium binding. Biochemistry, 20, 1653-1659. 

E. Ohtsuka, A. F. Markham, S, Nishikawa, S. Tanaka, T. Tanaka, T. Miyake, E. Nakagawa, and M, Ikehara, in Synthesis, Structure and Chemistry of Transfer Ribonucleic Acids and their Components, M. Wiewiorowski, ed., Polish Academy of Sciences, Poznan, 1976, pp. 173-185. 

Many eucaryotic phenylalanine transfer ribonucleic acids (tRNA ) contain fluorescent components at the position adjacent to the 3 -end of an anticodon. A few related hypermodified nucleosides 1 have been isolated, their structure has been elucidated, and their chemical synthesis been performed. 

The synthesis of a protein requires the mRNA as a template containing the full sequence of codons, including the codon to terminate synthesis. The ribosomes, which orchestrate protein synthesis, read the mRNA in the 5 —>3 direction. (The 5 end has a phosphate group on the 5 -carbon atom of a ribose moiety whereas the 3 end has a phospate group on the 3 -carbon atom of ribose). Protein biosynthesis requires a transfer ribonucleic acid (tRNA) to convey an amino acid to the growing peptide chain. tRNAs are specific for each codon and contain 60-95 nucleotides, a few of which have unusual structures. The 3 end of the tRNA has the sequence... 

Many unusual nucleotides have been found as minor components of nucleic acids, especially in the soluble or transfer ribonucleic acids. Most of these minor components contain methylated aglycons in their structure. A review of these nucleotides has been presented by Dekker, and general techniques for their isolation as nucleosides have been reported by Hall. In addition, 5,6-dihydrouridylic acid (34) has been isolated by enzymic hydrolysis of certain transfer ribonucleic acids from yeast, and 4-thiouridylic acid (35) was obtained from the alkaline hydrolyzate of transfer ribonucleic acid from Escherichia coli. A nucleotide whose ultraviolet absorption spectrum was very similar to that of 2-thiouridine has been reported to be present in transfer ribonucleic acid. Although the a anomer (36) of cytidylic acid has been detected (and identified) in a yeast ribonucleic acid hydrolyzate, it is not certain whether this -cytidylic acid is a minor component of ribonucleic acid or an artifact produced during the alkaline hydrolysis. Among the minor nucleotide components of transfer ribonucleic acid, pseudouridylic acid (37)89-98 jg unique, in that the D-ribosyl moiety is linked to the aglycon... 

RM Reference Material RNA ribonucleic acid (structural element of the cytoplasm and cell nucleus), consisting of D-ribose sugar, the nitrogenous bases adenine, guanine, cytosine and uracil. There are three different types transfer RNA, messenger RNA and ribosomal RNA RNAA radiochemical neutron activation analysis (post irradiation radiochemical separation)... 

Besides BSA, a single, broad peak was observed also for lysozyme, transfer ribonucleic acid (tRNA), and chondroitin sulfate [32,33]. It was concluded that an ordered structure was formed in these solutions at low salt conditions. For... 

In like manner, ribosomal ribonucleic acid (rRNA) and transfer ribonucleic acid (tRNA) are synthesized from their specific genes through the action of DNA-dependent RNA polymerase. And as in the case of mRNA, each of the precursor forms of these nucleotides are also processed until they reach their final forms. The rRNAs and a large variety of ribosomal proteins are assembled to form the ribosome. Ribosomes, the supramolecular structures in which protein synthesis takes place and which functionally resemble multienzyme complexes, are elaborate structures. They are attached, by a binding site on the smaller subribosomal particle, to the endoplasmic reticulum. The tRNAs that are synthesized finally become charged with specific amino acids. 

This chapter describes the application of P-NMR spectroscopy to the study of the conformation of transfer ribonucleic acids (tRNAs). The P-NMR spectrum of pure acceptor tRNA species has been shown to contain considerable fine structure (Figs. 1 and 2). High-resolution ip-NMR spectra by Gueron and Shulman (1975) and later by Salemink et al. (1979) and Gorenstein and Luxon (1979) revealed 16 individual phosphate resonances spread over 7 ppm that were not observed in earlier P tRNA spectra (Gueron, 1971 Weiner et al., 1974 Gorenstein and Kar, 1975). 

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. 

As we said earlier, nucleic acids are the architects and construction contractors for synthesizing proteins. There are two kinds of nucleic acids. DNA, or deoxyribonucleic acid, is the blueprint for synthesis of proteins. RNA, or ribonucleic acid, is the construction contractor. Messenger RNA reads the instructions for synthesis of a protein encoded on a strand of DNA and carries those instructions to the worksite, where transfer RNA brings the amino acids in for incorporation into the polypeptide chain. Now, let s take a closer look at the structures of DNA and RNA. 

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. 

In deoxyribonucleic acid (DNA) the carbohydrate is 2-deoxy-D-ribose, while in ribonucleic acid (RNA) the carbohydrate residue is ribose. Three types of RNA were recognized, and they can be messenger RNA (mRNA), transfer RNA (tRNA), or ribosomal RNA (rRNA), which is the most abundant in cells. Values between 10 and 10 Dalton have been reported for the molecular weight of DNA, and the molecular weight is about 10 for rRNA, 10 for mRNA, and lOMor rRNA. The simplified structures of DNA and RNA are the following ... 

One of the major achievements in all of science has been the identification, at the molecnlar level, of the chemical interactions that are involved in the transfer of genetic information and the control of protein biosynthesis. The substances involved are biological macromolecnles called nucleic acids. Nucleic acids were isolated over 100 years ago, and, as their name implies, they are acidic substances present in the nuclei of cells. There are two major kinds of nucleic acids ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). To understand the complex structure of nucleic acids, we first need to examine some simpler substances, nitrogen-containing aromatic heterocycles called pyrimidines and purines. The parent substance of each class and the numbering system used are shown ... 

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