Deoxyguanylic acid

Guanine, G Guanylic acid, GMP Deoxyguanylic acid, dGMP... 

DNA contains the bases adenine A), thymine (T), guanine (G), and cytosine (C). These bases are covalently attached to the deoxyribose phosphate to form nucleotides. The respective nucleotides are called dcoxyadenylic add (dA), deoxythy-midylic add (dT), deoxyguanylic acid (dC), and deoxycj tidylic acid (dC). The prefix "deoxy" indicates that the sugar is deoxyribose, rather than ribo e. The word "acid" indicates that the ribose con tains a covalently bound phosphoric acid group. 

Using the same rationale as is used above in the purine section, it can be seen from the results in the Table that an extensive back reaction of the deoxyguanylic acid -(Cl2") radical occurs. The slight radioprotective effect of chloride in acidic solutions of deoxycytidylic acid and deoxyadenylic acid may be caused by the inability of these compounds to react with Cl2". 

The rate constants for reaction of the Cl2" radical with the compounds investigated are much lower than the corresponding OH radical rate constants. The Cl2" rate constants for reaction with this series of compounds vary over a wider range than do their OH radical counterparts. The effect of this range of rate constants will be most evident in the radiolysis of mixtures of compounds. In the radiolysis of a mixture of equal concentrations of the deoxynucleotides, OH radicals cause approximately equal destruction of all four bases (4). Cl2" radicals, on the other hand, will react preferentially with deoxyguanylic acid and only a tenth of these reactions will cause base destruction. Thus, the net effect of conversion of OH radicals to Cl2" radicals, in this system, will be... 

Guanine G Guanylic acid GMP Deoxyguanylic acid dGMP... 

Anthramycin has previously been shown to react preferentially with helical, or native, DNA [6]. The reactive site appears to involve deoxyguanylic acid residues, since only guanine-containing deoxypolynucleotides are reactive [7]. The complex formed is extremely stable and resists dissociation by dialysis, gel filtration, alcohol precipitation, sodium lauryl sulfate and silver ion. In addition, separation of DNA strands by alkali de-naturation fails to dissociate bound anthramycin [8]. 

ECO RI ENDONUCLEASE. Eco RI endonuclease is one of the better studied endonucleases. It is a small protein of 276 amino acid residues (31,065 daltons) of known sequence (6,7). The active enzyme contains two subunits (8,9) and hydrolyzes the phospho-diester bond between the deoxyguanylic and deoxyadenylic acid residues of duplex 5 -GAATTC-3. On hydrolysis, there is an... 

Deoxyribonucleotides Monomeric units of DNA, including deoxyadenylic (dAMP), deoxyguanylic (dGMP), deoxycytidylic (dCMP), and deoxythymidylic (dTMP) acids. 

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