Nucleic Acids in Chemistry and Biology: RSC
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The structure, function and reactions of nucleic acids are central to molecular biology and are crucial for the understanding of complex biological processes involved. Revised and updated Nucleic Acids in Chemistry and Biology 3rd Edition discusses in detail, both the chemistry and biology of nucleic acids and brings RNA into parity with DNA. Written by leading experts, with extensive teaching experience, this new edition provides some updated and expanded coverage of nucleic acid chemistry, reactions and interactions with proteins and drugs. A brief history of the discovery of nucleic acids is followed by a molecularly based introduction to the structure and biological roles of DNA and RNA. Key chapters are devoted to the chemical synthesis of nucleosides and nucleotides, oligonucleotides and their analogues and to analytical techniques applied to nucleic acids. The text is supported by an extensive list of references, making it a definitive reference source. This authoritative book presents topics in an integrated manner and readable style. It is ideal for graduate and undergraduates students of chemistry and biochemistry, as well as new researchers to the field.
cleavage of DNA strands at a specific base residue. Consequently, all attention came to focus on the secondary structure of DNA. Two independent experiments in biophysics showed that DNA possesses an ordered secondary structure. Using a sample of DNA obtained from Hammarsten in 1938, Astbury obtained an X-ray diffraction pattern Introduction and Overview 5 HO NH2 N O P O N O HO N OH P O O NH2 HO deoxyadenylic acid [dAMP] deoxyguanylic acid [dGMP] (as enolic tautomer) H3C NH2
in a greater hydrophobic surface area of the bases being exposed in A-DNA per base pair. From this, it has been argued that B-DNA will have the lesser energy of solvation, explaining its greater stability at high humidity (95%) and that this hydrophobic effect may well tip the balance between the A- and B-form helices. Other B-DNA structures have much lower significance. C-DNA is obtained from the lithium salt of natural DNA at rather low humidity.2 It has 28 bases and three full turns of the
same strand and this leads to increased stacking stability in the double-helix. However, there is a penalty! The larger purine bases occupy the centre of the helix so that in alternating purine–pyrimidine sequences they overlap with neighbouring purines in the opposite strand. Consequently, propeller twist causes a clash between such pairs in adjacent purines in opposite strands. For pyrimidine-(3→5Ј)–purine steps, these purine–purine clashes take place in the minor groove where they involve
from C-1 of an aldose derivative by a nucleophilic nitrogen (or carbon) atom of the heterocyclic base. Second, the double disconnection B identifies the process of building a heterocyclic base onto a preformed nitrogen or carbon substituent at C-1 of the I NH2 O NH2 N N N HO O N HO N O N OH OH HO HO ara-adenosine ara-cytidine NH N HO O O HO O OH 5-iodouridine Figure 3.1 Modified nucleosides of biological importance C N O B HO O B N A HO HO O NH + HO N
TRANSLATION: The ability of E. coli DNA polymerase I to use a nick as a starting point from which one strand of a duplex DNA can be degraded and replaced by resynthesis of new material; is used to introduce radioactively labelled nucleotides into DNA in vitro. NONSENSE CODON: Any one of three triplets (UAG, UAA, UGA) that cause termination of protein synthesis (UAG is known as amber, UAA as ochre, UGA as opal). NORTHERN BLOTTING: A technique for transferring RNA from an agarose gel to a