Nucleic Acids Research

http://nar.oxfordjournals.org

List of Papers (Total 27,745)

Isolation and sequence determination of the 3′-terminal regions of isotopically labelled RNA molecules

The method which was developed for the selective Isolation of 3′-terminal polynucleotides from large RNA molecules on columns of cellulose derivatives containing covalently bound dihydroxyboryl groups has been modified and adapted for use on radioactively labelled RNAs. The 3′- terminal polynucleotide fragments which result from specific ribonuclease digestion of Isotopically...

Inducible and constitutive nucleoside-binding sites in Escherichia coli: differential inhibition by nucleoside analogues

Constitutive and inducible nucleoside-binding sites on the surface of the cell s of E. coli B have different patterns of inhibition by nucleoside analogues. 1(β-D-Ribofuranosyl)-4-aminopyrimidine-6-one and isoguanosine preferentially inhibit the inducible binding sites while showdomycin and N4-dimethyl-cytidine interfere more strongly with the constitutive function.

The nucleotide sequence preceding an RNA polymerase initiation site on SV40 DNA. Part 1. The sequence of the late strand transcript

The nucleotide sequence of the transcript of the “late” strand of the region of SV40 DNA preceding the preferred initiation site for Escherichia coli RNA polymerase has been determined to be U-G-U-A-A-C-C-A-U-U-A-U-A-A-G-C-U-G-C-A-A-U-A-A-A-C-A-A-G-U-U-A-A-C-A-A-C-A-A-C-A-A-U-U-G-Cp. Hemophilus influenza restriction endonuclease cleaves this region 30 nucleotides (base pairs...

Fractionation and characterization of satellite DNAs of the kangaroo rat (Dipodomys ordii)

Nuclear DNA from liver cells of the kangaroo rat species Dipodomys ordii was fractionated and characterized with the aid of buoyant density gradients in neutral and alkaline CsCl and in Ag+ -CS2SO4. More than one-half of the DNA was present in three density satellites, a greater proportion than in any other species yet reported; the purified satellite DNAs were denser than...

Synthesis of 1,N6-etheno-2-aza-adenosine (2-aza-ε-adenosine): a new cytotoxic fluorescent nucleoside

1,N6-Etheno-2-aza-adenosine was synthesized by treating 1,N6-etheno-adenosine with alkali, followed bv nitrosation. The mechanism of formation of this novel nucleoside was elucidated using adenosine tritiated at C-8 and C-2, and was found to deformylate exclusively at C-2. This new 2-aza nucleoside fluoresces at 494 nm when excited at 358 nm. Toxicity study showed the compound is...

Inhibition of nucleoside-binding sites by nucleoside analogues in Escherichia coli

Nucleoside analogues modified in heterocyclic bases or sugar moieties were screened for their ability of counter-acting the bacteriostatic effect of showdomycin in E. coli. Pyrimidine ribonucleosides or 2′-deoxyribonucleosides sub-stituted at the position 5 with halogen, atom, methyl or hydroxyl group, 2′-fluoro-, 2′-chloro-2′-deoxyuridine and its 5-methyl homologue, N4...

Polynucleotides. XXIV1. Synthesis and properties of a dinucleoside monophosphate derived from uridine 6,2-cyclonucleoside2

A dinucleoside ncnophosphate, 6,2′-anhydro-6-oxy-1-β-D–arabinofuranosyluracil-phosphoryl-(3′-5′)-6,2′-anhydro-6-oxy-1-β-D-arabinofuranosyluracil (I) was synthesized by the condensation reaction using DCC from 5′-monomethoxy-trityl derivative(VII) and 3′-acetyl-5′-phosphate(X) of the monomer units. Yield was ca.70%. UV of compound I shewed no hypochromicity and its CD spectrum...

A rapidly-banding component of animal DNA preparations that interferes with buoyant density studies

Rapidly-banding components of purified animal cell DNA's have been observed which have abnormal buoyant densities and show anomalous band profiles when centrifuged to equilibrium in cesium salts. These components interfere with the separation of animal DNA fractions and with the analysis of animal cell DNA's by buoyant density techniques. They can be detected by examining...

Template specificity of transcription during sporulation of Bacillus subtilis

Partially purified extracts from sporulating Bacillus subtilis cultures transcribed different natural DNAs with different efficiencies. This template specificity results in an increased or a decreased synthetic activity with respect to extracts from vegetative cells, depending on the template used. With SPP1 DNA a decrease in activity occurs, whereas with T7 DNA an increased...

The molecular complexity of Mu and Pi symbiont DNA of Paramecium aurelia

The molecular size of mu and pi symbionts of Paramecium aurelia has been calculated from renaturation kinetic data. Observed values were 0.78 × 109 daltons for mu particle DNA and 0.81 × 109 daltons for pi particle DNA. Estimates of analytical complexity were 4.45 × 109 and 5.05 × 109 daltons respectively. Based on these data, mu and pi symbionts appear to possess multiple...

Control of transcription of the reovirus genome

The ten double-stranded RNA segments of the reovirus genome are not transcribed at equal frequencies until later times during the course of infection. When an inhibitor of protein synthesis such as cycloheximide was added to infected cells at the beginning of infection, only four of the ten segments were transcribed. By two hr post infection, five and possibly seven of the...

Distribution of repetitious sequences in chick nuclear DNA

By an improved method of hydroxylapatite chromatography, the reassociated sequences of chick nuclear DNA were isolated, and their base composition analysed. By increasing the amount of reassociation, the G + C content of the renatured sequences decreased progressively to reach a mean value corresponding to that of the total DNA. In order to study the distribution of the families...

The purification and properties of hen oviduct form. B DNA-dependent RNA polymerase

Hen oviduct form B DNA-dependent RNA polymerase has been extensively purified and its properties analysed. It seems likely to consist of a mixture of two forms of the type observed in tissues from other species. Furthermore using SI nuclease to digest single-stranded DNA, we show that although form B can transcribe double-stranded DNA template it has a very strong preference for...

Effects of dilute HCl on yeast tRNAPhe and E. coli tRNA1fMet

HCl treatment of yeast tRNAPhe under conditions generally used for excision of ‘Y’ base results in structure and conformation changes as monitored by line widths i n the PMR spectra at 220 MHz and by optical rotation. Like exposure of E. coli causes similar changes in the PMR spectra and optical rotation although no residues are eliminated. Electrophoresis in polyacrylamide gels...

A method for the rapid preparation of 5-vinyluracil in high yield

A method for the rapid preparation of the thymineanalogue, 5-vinyluracil, in 83% yield from 5-(1-hydroxyethyl)uracil via the methanesulnhonyl ester is reported.

Polynucleotides. XXII(1). Synthesis and properties of poly 7-deazainosinic acid

Poly 7-deazainosinic acid has been prepared by the deamination and phosphorylation of tubercidin and the nucleoside diphosphate was polymerised using polynucleotide phosphorylase. The polymer has similar physical properties to poly(I), but has alow thermal stability in the double-stranded complex with poly(C). Poly(7-deaza I), in contrast, forms a more stable triple-stranded...

The selective reaction of methoxyamine with cytidine residues in mammalian initiator transfer ribonucleic acid

Methoxyamine reacts selectively with tRNA molecules at certain exposed cytosine residues usually located in non base-paired regions of the two dimensional clover leaf structure. Here methoxyamine is used for the first time in a study of a mammalian tRNA structure. One of the sequence abnormalities of myeloma initiator tRNA is a cytosine instead of the usual uracil immediately...

2′-O-Methyl ribothymidine: a component of rabbit liver lysine transfer RNA

One of the lysine transfer RNAs of rabbit liver is shown to contain 2′-O-methyl ribothymidine in place of ribothymidine. This represents the first demonstration of the presence of 2′-O- methyl ribothymidine in a nucleic acid.

Aliphatic analogues of nucleotides: synthesis and affinity towards nucleases

DL-1-(2,3-Dihydroxypropyl) thymine waa prepared by Hilbert-Johns on reaction of 2,4-dimethoxy-5-methylpyrimidine with allyl bromide followed by the osmium tetroxide catalyzed hydroxyltion of the l-allyl-4-methoxy-5-methylpyrimidin-2-one obtained as an intermediate. The D-glycero enantiomer, R-1-(2,3-dihydroxypropyl) thymine and the corresponding 1-substituted uracil derivative...

Partial purification and characterization of four endodeoxyribonuclease activities from Escherichia coli K-12

Four hitherto undescribed endodeoxyribonucleases, temporarily designated A1, A2, A3, and B, have been isolated from E. coli K-12. Each requires Mg++ and is not stimulated by ATP or S-adenosylmethionine. A3 is strongly inhibited by Fe+++ and weakly inhibited by ATP, S-adenosylmethionine, and DPN, whereas B is inhibited by caffeine. Each can be purified free of exonuclease or DNA-3...