abstract：:The log kobs vs. pH profiles were determined in the intermediate acidity region for the glycosyl hydrolysis of guanosine and its 8-amino, 8-monomethylamino, 8-dimethylamino and 8-bromo derivatives. The decreased rate of the 8-amino and enhanced rate of the 8-bromo compound compared to guanosine support an A type mecha...

journal_title：Nucleic acids research

authors： Jordan F,Niv H

更新日期：1977-03-01 00:00:00

abstract：:The binding of nine aminoalkyl adenylates to isoleucyl-tRNA synthetase from Escherichia coli MRE 600 was measured and compared with the binding of the cognate amino acids. It was found that they bind rather tightly to the enzyme, the Kd's ranging from 3.1.10(-4) M with glycinol-AMP ester to 3.7.10(-9) M with L-isoleuc...

journal_title：Nucleic acids research

authors： Flossdorf J,Marutzky R,Messer K,Kula MR

更新日期：1977-03-01 00:00:00

abstract：:The effect of temperature and primer concentration on oligonucleotide-primed transcription has been studied using the separated strands of a well-defined natural DNA as template. Results were similar to those obtained in the homopolymer-directed model systems. At high temperature and excess primer concentration mainly...

journal_title：Nucleic acids research

authors： Van Kreijl CF,Beelen RH,Borst P

更新日期：1977-02-01 00:00:00

abstract：:Synchronous plasmodia of cycloheximide-sensitive and cycloheximide-resistant strains of Physarum polycephalum were labelled with 3[H]-deoxyadenosine in pulse and pulse-chase experiments in presence and absence of cycloheximide. The replication products were studied with alkaline sucrose gradient sedimentation analysis...

journal_title：Nucleic acids research

authors： Funderud S,Haugli F

更新日期：1977-02-01 00:00:00

abstract：:The method employed to determine the sequence of a T1 RNase fragment, A-A-A-A-A-U-A-A-C-A-A-U-A-C-A-Gp, from Novikoff rat hepatoma 18S ribosomal RNA is described. This method is applicable to any oligoribonucleotide produced by specific endonucleases that leave the newly cleaved 5'-end free for labeling with polynucle...

journal_title：Nucleic acids research

authors： Fuke M,Busch H

更新日期：1977-02-01 00:00:00

abstract：:The mitochondrial DNA of Neurospora crassa has a heterogeneous intramolecular base distribution. A contiguous piece, representing at least 30% of the total genome, has a G+C content that is 6% lower than the overall G+C content of the DNA. The genes for both ribosomal RNAs are contained in the remaining, relatively G+...

journal_title：Nucleic acids research

authors： Terpstra P,Holtrop M,Kroon A

更新日期：1977-01-01 00:00:00

abstract：:Yeast tRNA Val 1 alkylation with 2', 3'-O-4-(N-2-chloroethyl-N-methylamino) benzylidene d(pC-G)-A proceeds at 20 degrees - 30 degrees C in the complementary complexes which are formed by d(pC-G)-A greater than RC1 binding to 3 sequences of tRNA Val 1 : psi-C-G58 in the T loop, C-G40 at the 3'-side of the anticodon loo...

journal_title：Nucleic acids research

authors： Grineva NI,Karpova GG,Kuznetsova LM,Venkstern TV,Bayev AA

更新日期：1977-01-01 00:00:00

abstract：:DNA swivel (nicking-rejoining) enzyme activity has been studied in various cell fractions of a human lymphoid cell line. Swivel activity is found only in chromatin and in a nuclear membrane fraction containing DNA and possessing endogenous DNA synthesizing activity. Twenty percent of the total swivel activity and less...

journal_title：Nucleic acids research

authors： Yoshida S,Ungers G,Rosenberg BH

更新日期：1977-01-01 00:00:00

abstract：:The thermal stabilities of RNA:DNA hybrids are substantially greater than those of DNA:DNA duplexes in aqueous electrolyte solutions containing high concentrations of formamide. Association rates to form DNA:DNA duplexes and DNA:RNA hybrids have been measured in these solvents. There is a temperature range in which DN...

journal_title：Nucleic acids research

authors： Casey J,Davidson N

更新日期：1977-01-01 00:00:00

abstract：:The discontinuous synthesis of the complementary strands of polyoma DNA in isolated nuclei has been studied by hybridization techniques. The relative amounts of the newly synthesized complementary strands were compared by separately annealing them to denatured HpaII restriction fragments. In every case an excess (1.4-...

journal_title：Nucleic acids research

authors： Flory PJ Jr

更新日期：1977-01-01 00:00:00

abstract：:Superhelical PM2 DNA can be photochemically modified by u.v. irradiation. The variation of S20,w with dose shows the following characteristics. There is a linear increase from 28 to 31s produced by a low dose of u.v. irradiation (4,000 ergs/mm2). A plateau in S20,w occurs between 4,000 and 10,000 ergs/mm2. The S20,w t...

journal_title：Nucleic acids research

authors： Woodworth-Gutai M,Lebowitz J,Kato AC,Denhardt DT

更新日期：1977-01-01 00:00:00

abstract：:DNA bearing lambda operator sequences was methylated by dimethyl sulfate (DMS) in the presence or absence of lambda repressor. Under the experimental conditions, DMS methylates only the purine residues. The presence of lambda repressor affects only the methylation of certain G residues in the operators. Repressor bloc...

journal_title：Nucleic acids research

authors： Humayun Z,Kleid D,Ptashne M

更新日期：1977-01-01 00:00:00

abstract：:The variation of the proton chemical shifts due to the formation intermolecular hydrogen bonds is computed for a number of complexes which can be formed between the bases of the nucleic acids. The shifts expected for the isolated base pairs, in particular for the G-N1 H, T(or U)-N3H protons and the protons of the amin...

journal_title：Nucleic acids research

authors： Giessner-Prettre C,Pullman B,Caillet J

更新日期：1977-01-01 00:00:00

abstract：:We have formed complexes of relaxed closed circular Col E1 DNA with various combinations of histones, and examined the effects of treating the complexes with nicking-closing enzyme. Germond et al (1) have shown that when a mixture of the four core histones of the nucleosome (HIA, H2B, H3 and H4) is used in such an exp...

journal_title：Nucleic acids research

authors： Camerini-Otero RD,Felsenfeld G

更新日期：1977-01-01 00:00:00

abstract：:Synchronized cells of a normal human lymphocytic cell line contain little swiven enzyme activity in G0 and G1 and high activity in Sphase. The level of activity in different growth phase appears to be related to the fraction of the population engaged in DNA replication. No endogenous inhibitor or activator of swiven a...

journal_title：Nucleic acids research

authors： Rosenberg BH,Ungers G,Deutsch JF

更新日期：1976-12-01 00:00:00

abstract：:The binding of anti poly(I). poly (C) Fab fragments to double or triple stranded polynucletides has been studied by fluorescence. Association constants were deduced from competition experiments. The comparison of the association constants leads to the conclusion that several atoms of the base residues do not interact ...

journal_title：Nucleic acids research

authors： Guigues M,Leng M

更新日期：1976-12-01 00:00:00

abstract：:Deproteinated 16S RNA was iodinated at pH 5.0 in an aqueous solution containing TlCl3 plus KI for 1-5 hours at 42 degrees C. Under these conditions 33 moles of iodine are incorporated per mole of RNA. As judged by sucrose gradient sedimentation, the iodinated RNA does not exhibit any large alteration in conformation a...

journal_title：Nucleic acids research

authors： Schendel PL,Craven GR

更新日期：1976-11-01 00:00:00

abstract：:A circular denaturation and restriction map of mitochondrial DNA from Neurospora crassa is presented. The map shows the position of all twelve fragments produced by restriction endonuclease Eco R I and the position of the largest Hin III fragment along the previously established map of AT-rich sequences. The two wild ...

journal_title：Nucleic acids research

authors： Bernard U,Goldthwaite C,Küntzel H

更新日期：1976-11-01 00:00:00

abstract：:A mass spectral method is described for the detection and identification of unusual nucleotide residues present in DNAs. Analysis by this method of intact, underivatized DNA from salmon sperm, calf thymus, mouse L-cells, wheat germ, M. lysodeikticus, E. Coli, and the bacteriophages 0X-174, fd, and lamda, yields diagno...

journal_title：Nucleic acids research

authors： Wiebers JL

更新日期：1976-11-01 00:00:00

abstract：:Detailed models are presented for the triple-stranded polynucleotide helices of poly (U)-poly (A)-poly (U) (two forms), poly (U)-poly d (A) -poly (U), poly d(C)-poly d(I)-poly d(C), poly d(T)-polyd(A)-poly d(T) and poly (I)-poly (A)-poly (I). The models were genrated using a computerized, linked-atom procedure which p...

journal_title：Nucleic acids research

authors： Arnott S,Bond PJ,Selsing E,Smith PJ

更新日期：1976-10-01 00:00:00

abstract：:Phosphorylation of the easily accessible 3',5'-diesters 1a-d with diphenyl phosphorochloridate, followed by selective 5'-deacylation, affords the phosphotriester derivatives 2a-d in good yields. Alkaline treatment of 2a-d results in the formation of the 2',3'-cyclic phosphates (3a-d). The usefulness of the phosphotrie...

journal_title：Nucleic acids research

authors： van Boom JH,Burgers PM,Haasnoot CA

更新日期：1976-10-01 00:00:00

abstract：:Two of the tRNA's found in rabbit reticulocytes are substrates for a post-transcriptional modification leading to the incorporation of guanine into the polynucleotide chain. The major guanylated tRNA was previously identified as tRNA (His). In the present report we show that the minor guanylated tRNA is tRNA (Asn), an...

journal_title：Nucleic acids research

authors： Farkas WR,Chernoff D

更新日期：1976-10-01 00:00:00

abstract：:We studied the interaction of ethidium bromide with rye and calf thymus chromatin. Both types of chromatin have the same dye accessibility, which is about 50% of that of DNA. From this result we conclude that the molecular structure of these two chromatins is similar. For rye, the extraction of H1 produces no change i...

journal_title：Nucleic acids research

authors： LaRue H,Pallotta D

更新日期：1976-09-01 00:00:00

abstract：:The lambdagt clones containing fragments of the Drosophila melanogaster genome were prepared and characterized by hybridization of their DNA with (I) lambdagt-cRNA; (2) lambdaC-cRNA; (3) Dm-cRNA; (4) the mRNA of D.melanogaster culture cells and (5) the stable cytoplasmic poly (A) RNA from the same source. The techniqu...

journal_title：Nucleic acids research

authors： Ilyin YV,Tchurikov NA,Georgiev

更新日期：1976-08-01 00:00:00

abstract：:Poly 2'-azido-2'-deoxyadenylic acid (Poly Az) was synthesized from 2'-azido-2'-deoxyadenosine diphosphate by polynucleotide phosphorylase. Poly (Az) has U.V. absorption properties similar to poly (A) and hypochromicity of 40% at 0.1 M Na+ and neutrality. CD curve also resembled to that of poly (A), but has smaller ell...

journal_title：Nucleic acids research

authors： Ikehara M,Fukui T,Kakiuchi N

更新日期：1976-08-01 00:00:00

abstract：:No analogous nucleoside triphosphate was found which acts as well as ATP in binding to and supporting catalysis of leucyl-tRNA synthetase from Escherichia coli MRE 600. However, there are numerous nucleotides which are able to replace ATP, but with lower efficiency. The 6-amino group of the adenine ring and the 2'-hyd...

journal_title：Nucleic acids research

authors： Marutzky R,Flossdorf J,Kula MR

更新日期：1976-08-01 00:00:00

abstract：:Circular dichroism in the 300-360 nm region and fluorescence induced by intercaltating binding of ethidum bromide to both DNA and RNA components were studied in isolated HeLa nucleoli. Both DNA and RNA compoents contribute to the induced dichroic elliticity. Digestion of nucleoli by RNase or DNase shows that most of t...

journal_title：Nucleic acids research

authors： Huang CH,Baserga R

更新日期：1976-08-01 00:00:00

abstract：:In order to further elucidate the mechanism of tRNA methylase-tRNA intreaction the methylation of some individual tRNAs separately and by pairs was performed. In conditions of tRNA excess the methylation rates of positionally analogous nucleotides in tRNA molecules are not summed up when two substrates are simultaneou...

journal_title：Nucleic acids research

authors： Gambaryan AS,Venkstern TV,Bayev AA

更新日期：1976-08-01 00:00:00

abstract：:A sequence of 89 nucleotides from rabbit beta-globin mRNA has been determined and is shown to code for residues 107 to 137 of the beta-globin protein. In addition, a sequence heterogeneity has been identified within this 89 nucleotide long sequence which corresponds to a known polymorphic variant of rabbit beta-globin...

journal_title：Nucleic acids research

authors： Proudfoot NJ

更新日期：1976-07-01 00:00:00

abstract：:Photoalkylation reactions with 2-propanol, initiated with di-tert-butyl peroxide, of a variety of purine and pyrimidine mononucleotides and dinucleoside monophosphates lead to the substitution of an alpha-hydroxyisopropyl group for the H-8 atom of adenosine and the addition of the alcohol across the 5,6-double bond of...

journal_title：Nucleic acids research

authors： Havron A,Sperling J,Elad D

更新日期：1976-07-01 00:00:00

abstract：:The effects of Mg++, Mn++, and KCl addition, individually and in combination, on the rate of DNA- and RNA-primed DNA synthesis by avian myeloblastosis virus DNA polymerase (reverse transcriptase) using a variety of natural and synthetic template-primer combinations were examined. Optimal divalent cation concentrations...

journal_title：Nucleic acids research

authors： Marcus SL,Modak MJ

更新日期：1976-06-01 00:00:00

abstract：:Molecules of single-stranded ribosomal RNA and double-stranded replicative form of phage f2 RNA (dsRNA) adopt a compact form in solutions, containing sufficiently high concentrations of salt (NaCl) and polymer (PEG). However, only in the cases of native dsRNA molecules the compact particles are characterized by a regu...

journal_title：Nucleic acids research

authors： Evdokimov YM,Pyatigorskaya TL,Kadikov VA,Polyvtsev OF,Doskocil J,Koudelka J,Varshavsky YM

更新日期：1976-06-01 00:00:00

abstract：:Stacking self-association equilibria in aqueous solutions of m3uridine, m34,2',3',5'uridine, 2'-deoxyuridine, m13,4,4cytosine, m14,4,4,5cytosine, s2cytidine and s4thymidine were studied at various temperatures by vapour-pressure osmometry. Equilibrium constants Kst's were computed on the assumption of the isodesmic mo...

journal_title：Nucleic acids research

authors： Plesiewicz E,Stepień E,Bolewska K,Wierzchowski KL

更新日期：1976-05-01 00:00:00

abstract：:Vitamin C breaks DNA only in the presence of oxygen. Superoxide dismutase has no effect on the reaction but catalase suppresses it. Superoxide also gives rise to breaks in DNA suppressible by both superoxide dismutase and catalase. The hydroxyl radical seems to be the agent responsible for strand cleavage itself. ...

journal_title：Nucleic acids research

authors： Morgan AR,Cone RL,Elgert TM

更新日期：1976-05-01 00:00:00

abstract：:Hydroxylapatite chromatographies of mitochondrial and total enzymes from a rho+ yeast, or from the related rho degrees mitochondrial DNA-less mutant, show the occurrence in the mitochondrial enzyme of one Phe-, one Met-, one Leu-tRNA synthetase peak which elutes distinctly from the cytoplasmic counterpart and charges ...

journal_title：Nucleic acids research

authors： Schneller JM,Schneller C,Martin R,Stahl AJ

更新日期：1976-05-01 00:00:00

abstract：:The transfer ribonucleic acids (tRNAs) of B. subtilis at different growth phases are examined for changes in the composition and the methylation of minor constituents. The composition of the tRNAs indicates about equal amounts of adenosine and uridine, and of guanosine and cytidine. About 3-4 residues are present as m...

journal_title：Nucleic acids research

authors： Singhal RP,Vold B

更新日期：1976-05-01 00:00:00

abstract：:We have compared the properties of the poly(rA).oligo(dT) complex with those of the poly(rU).oligo(dA)n complex. Three main differences were found. First, poly(rA) and oligo(dT)n do not form a complex in concentrations of CsCl exceeding 2 M because the poly(rA) is insoluble in high salt. If the complex is made in low ...

journal_title：Nucleic acids research

authors： Mol JN,Borst P

更新日期：1976-04-01 00:00:00

abstract：:Homopolyribonucleotides and E. coli DNA wer spin labeled with an iodoacetamide-nitroxide compound. The extent of labeling is highly dependent upon the nature of the base and the secondary structure of the nucleic acid. This spin label-polymer linkage is unstable at high temperatures and in phosphate buffers. In order ...

journal_title：Nucleic acids research

authors： Caspary WJ,Greene JJ,Stempel LM,Ts'o PO

更新日期：1976-04-01 00:00:00

abstract：:Yeast tRNA Lys2 codes preferentially for AAA and contains a 2-thiouridine derivative (U) at the 5'-position of the anticodon. Removal of the 2-thio group from U by treatment with CNBr did not affect the amino acid accepting activity of the modified tRNA Lys2. CNBr treated tRNA Lys2 was active in protein synthesis but ...

journal_title：Nucleic acids research

authors： Sen GC,Ghosh HP

更新日期：1976-03-01 00:00:00

abstract：:Poly 2'0-ethylcytidylic acid (poly (Ce)) was prepared by polymerization of 2'-0-ethylcytidine-5'-pyrophosphate with Escherichia coli polynucleotide phosphorylase in the presence of Mn++, and its properties compared with those of poly (rC), poly (Cm) and poly (dC). The neutral form of pOLY (Ce) exhibits properties simi...

journal_title：Nucleic acids research

authors： Kielanowska M,Shugar D

更新日期：1976-03-01 00:00:00