DNA storage

The required template is a strand of DNA, for, as it will be recalled, during the process of transcription, the genetic message from the DNA storage form is transferred to the RNA polymer (so-called mRNA). Only one of the two DNA strands serves as a template. However, a RNA primer is not required to initiate synthesis. Instead, the enzyme binds to a specific region of the DNA strand and from this point proceeds with RNA synthesis the so-called promoter region. The reaction catalyzed may be represented as follows ... 

Nucleic acids are acidic substances present m the nuclei of cells and were known long before anyone suspected they were the primary substances involved m the storage transmission and processing of genetic information There are two kinds of nucleic acids ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) Both are complicated biopolymers based on three structural units a carbohydrate a phosphate ester linkage between carbohydrates and a heterocyclic aromatic compound The heterocyclic aro matic compounds are referred to as purine and pyrimidine bases We 11 begin with them and follow the structural thread... 

RNA structures, compared to the helical motifs that dominate DNA, are quite diverse, assuming various loop conformations in addition to helical structures. This diversity allows RNA molecules to assume a wide variety of tertiary structures with many biological functions beyond the storage and propagation of the genetic code. Examples include transfer RNA, which is involved in the translation of mRNA into proteins, the RNA components of ribosomes, the translation machinery, and catalytic RNA molecules. In addition, it is now known that secondary and tertiary elements of mRNA can act to regulate the translation of its own primary sequence. Such diversity makes RNA a prime area for the study of structure-function relationships to which computational approaches can make a significant contribution. 

In retrospect it is easy to see that such structural irregularity is actually required for proteins to fulfill their diverse functions. Information storage and transfer from DNA is essentially linear, and DNA molecules of very different information content can therefore have essentially the same gross structure. In contrast, proteins must recognize many thousands of different molecules in the cell by detailed three-dimensional interactions, which... 

Metabolic Myopathies Glycogen Storage Disease Disorders of Lipid Metabolism Respiratory Chain Disorders Mitochondrial DNA Abnormalities Myotonias, Periodic Paralyses, and Malignant Hyperpyrexia Myotonias... 

Deoxyribonucleic acid (DNA) is a very important biopolymer with the function of storage and transmission of genetic information. In this reason the protection of structural integrity and functional activity of DNA is essential for the viability of living systems, as well as the effectiveness of laboratory DNA-technics. 

DNA and RNA are formed of nucleotides. Each nucleotide or nucleoside is composed of a purine or pyrimidine base linked to the 1-position of a ribose sugar in the case of RNA and a 2 -deoxyribose sugar in the case of DNA.155 The 5 position is phosphorylated in the case of a nucleotide, while the nucleoside is not phosphorylated therefore, nucleotides are nucleoside phosphates. Phosphorylation can include one, two, or three phosphate groups. The most familiar example of a phosphorylated nucleotide is phosphorylated adenosine, which occurs as the mono-, di-, and triphosphate (AMP, ADP, and ATP, respectively) and is a principal means of energy storage in biological systems. 

It has been suggested (Bozzi et ah, 1997 Grant et ah, 1998) that Dps and E. inocua ferritin represent examples of a family of ancestral dodecameric protein which had as function to trap, but not to mineralize, metal ions, and that the ability to oxidize and mineralize iron efficiently and to form fourfold interactions came later. The hollow-cored dodecameric motif exemplified by Dps and E. inocua ferritin has clearly been adapted to a number of functions, since in addition to DNA binding and iron storage, other family members include a novel pilin, a bromoperoxidase and several other proteins of unknown function (Grant et ah, 1998). 

The iron storage protein ferritin is a small 20 kDa a-helical protein that spontaneously assembles into a hollow ball-like homo-24-mer. The outer diameter of the sphere is circa 12 nm and the inner diameter, or core diameter, is circa 8 nm. A smaller version, known as miniferritin or Dps protein (Dps = DNA protecting... 

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