Molecular biology ribosome

In contrast, RNA occurs in multiple copies and various forms (Table 11.2). Cells contain up to eight times as much RNA as DNA. RNA has a number of important biological functions, and on this basis, RNA molecules are categorized into several major types messenger RNA, ribosomal RNA, and transfer RNA. Eukaryotic cells contain an additional type, small nuclear RNA (snRNA). With these basic definitions in mind, let s now briefly consider the chemical and structural nature of DNA and the various RNAs. Chapter 12 elaborates on methods to determine the primary structure of nucleic acids by sequencing methods and discusses the secondary and tertiary structures of DNA and RNA. Part rV, Information Transfer, includes a detailed treatment of the dynamic role of nucleic acids in the molecular biology of the cell. 

Fitch, D.H.A., Bugaj-gaweda, B. and Emmons, S.W. (1995) 18S ribosomal gene phylogeny for some rhabditidae related to Caenorhabditis elegans. Molecular Biology and Evolution 12, 346-358. 

The electron microscope (EM) has been used extensively in molecular biological research (1). Among its many applications, EM has been used to visualize polyribosomal structure (2), to visualize ribosome substructure (3), and to visualize the elongation factor Tu on the Escherichia... 

Antibiotics can be classified according to their effects on the biochemistry or molecular biology of pathogens. There are ribosomal inhibitors (macrolides), cell wall disrupters 0-lactams), DNA disturbers (fluoroquinolones), and metabolic poisons (trimethoprim-sulfamethoxazole). Antibiotics also can be classified according to whether they are static (inhibitory) or cidal (lethal). The classification of drugs as either static or cidal is based on laboratory assessment of the interaction of pathogen and antibiotic drug. 

Mukha, D. V., Wiegmann, . M. and Schal, C. (2002). Evolution and phylogenetic information content of the ribosomal DNA repeat unit in the Blattodea (Insecta). Insect Biochemistry and Molecular Biology 32 951-960. 

As any elementary textbook on molecular biology will relate, the sequences of proteins are stored in DNA in the form of a triplet code. Each amino acid is encoded by one or more triplet combinations of the four bases A, T, G, and C. For example, tryptophan is coded by the sequence TGG. The sequence of triplets is converted into a protein by a process in which DNA is first transcribed into mRNA. This message is then translated into protein on the ribosomes in conjunction with tRNA and the aminoacyl-tRNA synthetases. In prokaryotes, there is a one-to-one relationship between the sequence of triplets in the DNA. and the sequence of amino acids in the protein. In eukaryotes, the DNA often contains stretches of intervening sequences or introns which are excised from the mRNA after transcription (Chapter 1). 

Krayevsky, A. A., Kukhanova, M. K. The peptidyltransferase center of ribosomes, in Progress in Nucleic Acid Research and Molecular Biology, Vol. 23, p. 1, New York, Academic Press 1979... 

Chapters 11 through 14 deal with aspects of molecular biology in archaea and include, respectively, DNA structure and replication by P. Forterre transcription apparatus by W. Zillig et al. translation apparatus by R. Amils et al. and ribosomal structure and function by A. Matheson et al. 

Vicens, Q. Westhof, E. Crystal Structure of Geneticin Bound to a Bacterial 16 S Ribosomal RNA A Site Oligonucleotide. Journal of Molecular Biology, 326, 1175-1188 (2003). 

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