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91.
The paper represents a further development of our hydrate hypothesis of simplest living matter origination (SLMO) from inorganic and simplest organic mineral substances. It is supposed that the sources of SLMO are simplest aliphatic hydrocarbons, niters, and phosphates. Thermodynamic calculations demonstrating a principal possibility for simultaneous syntheses of different nitrogen bases, d-ribose, and desoxy-d-ribose from these source substances are presented. The most probable principal mechanism of SLMO and the principal conditions necessary for realization of the proposed chemism of SLMO in the framework of the proposed mechanism are considered. A principal means for testing the hypothesis is proposed. 相似文献
92.
Determination of DNA using sodium 9,10-anthraquinone-2-sulfonate as an in situ photochemical fluorescence probe 总被引:2,自引:0,他引:2
Wen-You Li Xiang-Qun Guo Jin-Gou Xu Qing-Zhi Zhu Yi-Bing Zhao 《Analytica chimica acta》1997,340(1-3):291-296
An in situ photochemical fluorescence probe method for the determination of DNA with sodium 9,10-anthraquinone-2-sulfonate (AQS) as a photochemical fluorescence probe was developed. It was based on the conversion of AQS into an intensively fluorescent product by irradiating with UV radiation. The photochemical reaction is retarded by DNA. The determination can be carried out by measuring the fluorescence intensity at a fixed time. The calibration graph was linear in the range 0–80 ng ml−1 calf thymus (CT) DNA (r = 0.9991), the limit of detection was 3.2 ng ml−1 CT DNA (n = 9). The kinetic behaviour of the photochemical reaction and the effects of experimental conditions were investigated and discussed in detail. The results of absorption spectra and competitive binding experiments suggested the interaction between AQS and DNA to be intercalative. 相似文献
93.
E. A. Belousova V. V. Koval N. I. Rechkunova S. Kh. Degtyarev O. S. Fedorova O. I. Lavrik 《Russian Chemical Bulletin》2005,54(5):1306-1310
The interaction of DNA polymerase Tte from Thermus thermophilus B35 with dUTP analog containing a fluorescein residue bound to C(5) of the base (Flu-dUTP) was studied by fluorescence titration.
The dissociation constants of the enzyme—substrate complexes in the absence and in the presence of a DNA duplex containing
an extended template and bivalent metal ions and the kinetic parameters of polymerization by DNA polymerase Tte in the presence of Flu-dUTP were determined.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1268–1272, May, 2005. 相似文献
94.
Fernando Ferreira 《Tetrahedron letters》2004,45(33):6287-6290
Oligonucleotides protected with N-(trimethylsilylethoxycarbonyl) (Teoc) and P-(trimethylsilylethanol) (Tse) groups were synthesized and deprotected by a single ZnBr2 treatment. Teoc group stabilized dA against depurination. This strategy was applied to the synthesis of base-sensitive oligonucleotide prodrugs bearing S-acetyl-2-thioethyl (Sate) phosphotriesters. 相似文献
95.
96.
IDENTIFICATION OF PARTIAL MUTATIONAL SITES IN HUMAN MITOCHONDRIAL DNA IN THE CHINESE AND ITS SIGNIFICANCE 总被引:1,自引:0,他引:1
A simple method for the identification of mutational sites in human mitochondrial DNA (mtDNA) was described. It was based on the human Cambridge sequence as a relative standard sequence and a single base pair substitution in mtDNA as a unique mutational form. The partial mutational sites can be determined using this method which was characterized by combining the restriction mapping with the analysis for the table of human mtDNA potential mutational sites with rapidity and simplicity. In the meanwhile, six mtDNA mutational sites found in Chinese population were identified by means of this method. 相似文献
97.
Weiping Wang Bo Liao Tianming Wang Wen Zhu 《International journal of quantum chemistry》2006,106(9):1998-2005
A 3D graphical representation of DNA sequences, which has no circuit or degeneracy, is derived for mathematical denotation of DNA sequence. Based on this graphical representation, we propose a new sequence distance measure. We make use of the corresponding similarity matrix to construct a phylogenic tree by virtue of the fuzzy theory. The examination of phylogenic tree belong to eight species illustrates the utility of our approach. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 相似文献
98.
99.
Hui Chen 《Analytica chimica acta》2003,478(1):31-36
A high sensitive flow-injection chemiluminescence method for determination of calf thymus DNA and herring sperm DNA has been developed. The method is based on the chemiluminescence reaction of Rhodamine B-cerium(IV)-thermally denatured DNAs in sulfuric acid media. The proposed procedure allows quantitation of DNAs in the range 2.6×10−5 to 0.26 μg ml−1 for calf thymus DNA and 5.0×10−8 to 5.0×10−5 μg ml−1 for herring sperm DNA with correlation coefficients 0.9998 and 0.9996 (both n=11), respectively. The detection limits (3σ) are 6.5×10−6 μg ml−1 for calf thymus DNA and 4.3×10−8 μg ml−1 for herring sperm DNA. The possible mechanism of chemiluminescence in the system is discussed. 相似文献
100.
A resonance light scattering (RLS) imaging method was proposed based on imaging and measuring the RLS features of single suprahelical species of DNA, and its appfication to DNA assay was also investigated. In acidic medium, porphine-5,10,15,20-tetrakis(p-phenyltlimethylaminium) (PTPTMA), could stack along the molecular surface of DNA with the mode of long-range assembly to induce the formation of suprahelical species of DNA, resulting in strong RLS signals in the range of 450-510 nm. Under the excitation of 488 nm fight beam of argon ion laser source, single suprahelical species could be observed with the aid of a common microscope due to the strong scattered fight emitted by the suprahelical species. By capturing the RLS images of the single suprahelical species with a cooled charge coupled device (CCD) camera, and analyzing the RLS data, herein an RLS imaging method of DNA was proposed based on the linear relationship between the counts of suprahelical species in the detection focus plane and the concentration of DNA in nanograms. When 1.8 μmol/L PTPTMA was employed, both calf thymus DNA (ct DNA) and fish sperm DNA (fs DNA) in the range of 25-1100 ng/mL could be detected with the limits of detection lower than 25 ng/mL (3a). Four synthetic samples were detected satisfactorily with relative standard deviations less than 5.1%. 相似文献