Cytosine-5-phosphate

CpG stands for cytosine phosphate guanine dinucleotide in a particular sequence context. CpG motifs are responsible for proliferative effects of antisense oligonucleotides, particularly with respect to B-lymphocytes. Die optimal immune-stimulatory consensus sequence surrounding CpG is R1R2CGY1Y2, where R1 is a purine (mild preference for G), R2 is a purine or T (preference for A), and Y1 and Y2 are pyrimidines (preference for T). 

Cytosine-phosphate- guanine Nucelotide Binding to TLR9 and DC activity Vaccine adjuvant... 

Raman, R., Raguram, S., Venkataraman, G., Paulson, J.C., Sasisekharan, R., 2005. Glycomics an integrated systems approach to structure-function relationships of glycans. Nat. Methods 2,817-824. Rao, C., Tam, J.P., 1994. Synthesis of peptide dendrimer. J. Am. Chem. Soc. 16, 6975—6976. Rattanakiat, S., Nishikawa, M., Funabashi, H., Luo, D., Takakura, Y, 2009. The assembly of a short hnear natural cytosine-phosphate-guanine DNA into dendritic structures and its effect on immunostimulatory activity. Biomaterials 30 (29), 5701-5706. 

Section 28 8 The most common form of DNA is B DNA which exists as a right handed double helix The carbohydrate-phosphate backbone lies on the outside the punne and pyrimidine bases on the inside The double helix IS stabilized by complementary hydrogen bonding (base pairing) between adenine (A) and thymine (T) and guanine (G) and cytosine (C)... 

The primary stmcture of DNA is based on repeating nucleotide units, where each nucleotide is made up of the sugar, ie, 2 -deoxyribose, a phosphate, and a heterocycHc base, N. The most common DNA bases are the purines, adenine (A) and guanine (G), and the pyrimidines, thymine (T) and cytosine (C) (Fig. 1). The base, N, is bound at the I -position of the ribose unit through a heterocycHc nitrogen. 

Cytosine was isolated from hydrolysis of calf thymus in 1894 and by 1903 its structure was known and it had been synthesized from 2-ethylthiopyrimidin-4(3H)-one. The acid hydrolysis of ribonucleic acid gives nucleotides, among which are two cytidylic acids, 2 -and 3 -phosphates of cytidine further hydrolysis gives cytidine itself, i.e. the 1-/3-D-ribofuranoside of cytosine, and thence cytosine. The deoxyribonucleic acids likewise yield deoxyribonucleotides, including cytosine deoxyribose-5 -phosphate, from which the phosphate may be removed to give cytosine deoxyriboside and thence cytosine. 

The steps involved in automated oligonucleotide synthesis illustrate the current use of protective groups in phosphate chemistry (Scheme 1). Oligonucleotide synthesis involves the protection and deprotection of the 5 -OH, the amino groups on adenine, guanine, and cytosine, and -OH groups on phosphorus. 

DNA is made up ot two intertwined strands. A sugar-phosphate chain makes up the backbone of each, and the two strands are joined by way of hydrogen bonds betwen parrs of nucleotide bases, adenine, thymine, guanine and cytosine. Adenine may only pair with thymine and guanine with cytosine. The molecule adopts a helical structure (actually, a double helical stnrcture or double helix ). 

Kinoshita, Imoto etal.11 14) synthesized other anionic models, 5 (APVP), CPVP, UPVP, TPVA, HPVA, THPVA, and 6 (AMPPVA), by the polymer reaction of N-eoupled(2-dihydrogenphosphate)-ethylderivatives of nucleic acid bases (or adenosine-5 -phosphate, AMP) with polyvinylaleohol. A, C, U, T, H, and TH denote adenine, cytosine, uracil, thymin, hypoxanthine, and theophylline, respectively. The authors reported the apparent hypochromities of 3 to 16% for many kinds of mixtures of the models and DNA or RNA, as compiled in Table 1. However, for the mixtures APVA + RNA, HPVA + RNA HPVA + DNA, THPVA + RNA, CPVA + DNA and CPVA + RNA, no hypochromicity was detected. 

Ap4A, diadenosine tetraphosphate BBG, Brilliant blue green BzATP, 2 - 3 -0-(4-benzoyl-benzoyl)-ATP cAMP, cyclic AMP CCPA, chlorocyclopentyl adenosine CPA, cyclopentyl adenosine CTP, cytosine triphosphate DPCPX, 8-cyclopentyl-1,3-dipnopylxanthine IP3, inosine triphosphate lpsl, diinosine penta phosphate a,p-meATP, a,p-methylene ATP p.y-meATP, p.y-meihylene ATP 2-MeSADP, 2-methylthio ADP 2-MeSAMP, 2-methylthio AMP 2-MeSATP, 2-methylthio ATP NECA, 5 -W-ethylcarboxamido adenosine PPADS, pyridoxal-phosphate-6-azophenyl-2, 4 -disulfonic acid PLC, phospholipase C RB2, reactive blue 2 TNP-ATP, 2, 3 -0-(2,4,6-trinitrophenyl) ATP. 

Figure 35-1. A segment of one strand of a DNA molecule in which the purine and pyrimidine bases guanine (G), cytosine (C), thymine (T), and adenine (A) are held together by a phosphodiester backbone between 2 -de-oxyribosyl moieties attached to the nucleobases by an W-glycosidic bond. Note that the backbone has a polarity (ie,a direction). Convention dictates that a single-stranded DNA sequence is written in the 5 to 3 direction (ie, pGpCpTpA, where G, C,T, and A represent the four bases and p represents the interconnecting phosphates).

C13-0120. Draw the stracture of the nucleotide formed from cytosine, ribose, and a phosphate. 

Hydrolytic cleavage of the glycosidic bond holding the DNA bases to the sugar-phosphate backbone is typically a very slow process under physiological conditions (pH 7.4 37°C). Loss of the pyrimidine bases cytosine and thymine occurs with a rate constant of 1.5 X 10 s (ty2 = 14,700 years), while loss of the purine bases guanine and adenine proceeds slightly faster, with a rate constant of 3.0 X... 

Nucleotides can be linked together into oligonucleotides through a phosphate bridge at the 5 position of one ribose unit and the 3 position of another. The purine bases, adenine and guanine, have two heterocyclic rings, while the pyrimidines cytosine, thymine, and uracil have one. The structure of adenosine monophosphate is shown in Figure 11. 

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