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A-DNA, double helix

A DNA double helix as pic tured on a 1964 postage stamp issued by Israel... [Pg.5]

FIGURE 28 5 (a) Tube and (b) space filling models of a DNA double helix The carbohydrate-phosphate backbone is on the out side and can be roughly traced in (b) by the red oxygen atoms The blue atoms belong to the purine and pyrimidine bases and he on the inside The base pairing is more clearly seen in (a)... [Pg.1170]

Self-Tesi 13.11 A Consider the following mechanism for the formation of a DNA double helix from its strands A and B ... [Pg.673]

This activity is intended to be performed in conjunction with Experiment 66. Restriction endonucleases, or restriction enzymes, cleave DNA at specific base sequences, fragmenting the DNA into smaller pieces. The two strands of a DNA double helix are cleaved at different places, resulting in uneven fragments called sticky ends. Cleavage of DNA by restriction enzymes is a required first step in various types of DNA analysis, including DNA fingerprinting and recombinant DNA technology. [Pg.484]

The two strands of a DNA double helix are held together by hydrogen bonds between the bases two between A and T, and three between G and C. [Pg.545]

A DNA molecule is said to be supercoiled when the ends of a DNA double helix join to form a closed circle which then winds back upon itself. [Pg.447]

Problem 10-9. Consider two pyrimidine molecules, located in space so that the planes of both molecules are parallel to the y — 2 plane, such that a translahon along the a —axis by 3.4 A and a rotahon by 36° around the a —axis will bring the two into coincidence. (This geometry is an extremely rough model for part of one shand of a DNA double helix). continues... [Pg.99]

FIGURE 4. Typical outer-sphere interaction of [Mg(H20)5] with two GC base pairs in the major groove of a DNA double helix... [Pg.321]

The most striking conformational variant observed for a DNA double helix with Watson-Crick base pairing is referred to as the Z form. In Z DNA the backbone is twisted in the left-handed (counterclockwise) direction. This structure was first detected by Alex Rich and his co-workers (fig. 25.8). The Z form is a considerably slimmer helix than the B form and contains 12 bp/turn rather than 10. In the Z form, the planes of the base pairs are rotated approximately 180° with respect to the helix axis from their orientation in the B form (fig. 25.9). [Pg.635]

Starting at the far left, we see a water molecule, two common amino acids, alanine and tryptophan, a segment of a DNA double helix, a segment of a protein single helix, and the folded polypeptide chain of the enzyme copper, zinc superoxide dismutase or SOD. [Pg.865]

Front cover illustration A DNA double helix chemically modified at the N2 of a guanine residue to possess a y-aminobutyric acid (GABA) group. The molecular model was kindly provided by Dr. George Pack of the University of Illinois College of Medicine at Rockford. [Pg.3]

A simple sketch of mutually interacting DNA structures is given in Fig. 12b, in which star-like constructs are formed by the aggregation of four strands, each partially complementary to two other strands. This yields the formation of DNA stars with four arms, each made by a DNA double helix. Moreover, sequences are such that arms terminate with an overhang of a few unpaired bases, chosen so as to stick with the tips of other arms. In this way, structures of unlimited sizes can in principle be generated. [Pg.245]

The two grooves, major and minor, in a DNA double helix are structural features that can be readily recognized by many compounds. Typically, major groove binders share distinct traits from minor groove binders. [Pg.136]

There are some recent application of a mixed quantum classical description to investigate quantum dynamics in large CC. The absorbance of a photosynthetic light harvesting complex caused by electronic Frenkel-exciton formation has been considered in Ref. [23], and Refs. [24,25] focused on excitation energy transfer in a DNA double helix strand. In both cases, however, the considerations have been restricted to an approximate description based on the use of... [Pg.36]

DNA double helix In a DNA double helix, the two strands of DNA are wound round each other with the bases on the inside and the sugar-phosphate backbones on the outside. The two DNA chains are held together by hydrogen bonds between pairs of bases adenine (A) always pairs with thymine (T) and guanine (G) always pairs with cytosine (C). [Pg.147]

CT, and possible C4 and C5 sugar radicals have been observed in irradiated hydrated DNA at 77K [66], The CT sugar radical was reported by Razskazovskii et al. in a DNA double helix [69]. The C1 was also produced in double stranded DNA at 77 K by photoexcitation of the guanine cation radical [70], The C3 radical was reported to be 4.5% of the total radical yield in the duplex (d(CTCTCGAGAG)), x-irradiated and observed at 4 K [71], It is very likely that the DNA simulations could be improved with the inclusion of a small percentage of these typical sugar radicals. [Pg.517]

Gu J, Wang J, Rak J, Leszczynski L (2007). Findings on die electron-attachment-induced abasic site in a DNA double helix. Angew Chem Int Ed 46 3479—3481. [Pg.666]

Kg. 1 Mechanism of mutation in a DNA double helix, (a) Regular recognition, (b)... [Pg.221]

It has been calculated that the average length of a base pair in a DNA double helix is 3.4 A. The human genome (the complete set of all DNA in the nucleus of a human cell) contains about three billion base pairs of DNA. In centimeters, how long is the DNA in the human genome Assume that the DNA is stretched out and not coiled around proteins as it acmaUy is... [Pg.801]

A false-color scanning tunneling micrograph (STM) of a DNA double-helix molecule adsorbed on a graphite substrate. [Pg.929]


See other pages where A-DNA, double helix is mentioned: [Pg.376]    [Pg.160]    [Pg.15]    [Pg.1204]    [Pg.335]    [Pg.96]    [Pg.958]    [Pg.1552]    [Pg.1610]    [Pg.260]    [Pg.135]    [Pg.169]    [Pg.191]    [Pg.542]    [Pg.660]    [Pg.71]    [Pg.488]    [Pg.497]    [Pg.178]    [Pg.200]    [Pg.270]    [Pg.586]    [Pg.129]    [Pg.135]   
See also in sourсe #XX -- [ Pg.683 ]




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