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1.
Hong-Ju Yin An-Guo Zhang Li-Hua Gao Hua Zhao 《Nucleosides, nucleotides & nucleic acids》2020,39(4):592-614
AbstractDNA groove binders have been poorly studied as compared to the intercalators. A novel Ru(II) complex of [Ru(aeip)2(Haip)](PF6)2 {Haip?=?2-(9-anthryl)-1H-imidazo[4,5-f][1,10]phenanthroline and aeip = 2-(anthracen-9-yl)-1-ethyl-imidazo[4,5-f][1, 10]phenanthroline} is synthesized and characterized by elemental analysis, 1H NMR spectroscopy and mass spectrometry. The complex is evidenced to be a calf-thymus DNA groove binder with a large intrinsic binding constant of 106 M?1 order of magnitude as supported by UV–visible absorption spectral titrations, salt effects, DNA competitive binding with ethidium bromide, DNA melting experiment, DNA viscosity measurements and density functional theory calculations. The acid-base properties of the complex studied by UV–Vis spectrophotometric titrations are reported as well. 相似文献
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4.
Takashi Horiuchi Masumi Hidaka Masahiro Akiyama Hideo Nishitani Mutsuo Sekiguchi 《Molecular & general genetics : MGG》1987,210(3):394-398
Summary A 4.32 kb DNA fragment, on which the DNA replication terminus (terR) site of plasmid R 6K was located, was inserted into the unique EcoRI site of plasmid pUC9. To detect replication intermediate molecules with a replication fork halted at the terR site, a cell DNA extract was digested with EcoRI, electrophoresed through an agarose gel and stained with ethidium bromide. In addition to two major bands, one derived from vector DNA and the other from the ter insert fragment, two extra minor bands were detected. Following DNA-DNA hybridization and electron microscopic observation we concluded that the two minor bands corresponded to the two Y-shaped molecules, produced from the -shaped intermediate molecules by EcoRI digestion.Abbreviations Ap
ampicillin
- kb
kilobase pair(s)
- EtBr
ethidium bromide 相似文献
5.
Summary Germinating spores of the fungus Botryodiplodia theobromae incorporated guanine-8-C14 into both the nuclear DNA and mitochondrial DNA fractions. Ethidium bromide inhibited the synthesis of mitochondrial DNA without having a significant effect on nuclear DNA synthesis or on the rate and extent of spore germination. Rates of leucine and uracil incorporation and of oxygen uptake were not significantly affected by ethidium bromide until germination was nearly completed. Mitochondrial DNA synthesis is apparently not required for germination of the spores of B. theobromae but is probably essential to continued vegetative growth.Abbreviations DNA
deoxyribonucleic acid
- mit-DNA
mitochondrial DNA
- nuc-DNA
nuclear DNA
- RNA
ribonucleic acid
- EB
ethidium bromide
- Tris
tris (hydroxymethyl)aminomethane
Published with the approval of the Director as Paper No. 3331, Journal Series, Nebraska Agricultural Experiment Station. Research reported was conducted under Project No. 21-17. Paper No. 7877, Scientific Journal Series, Minnesota Agricultural Experiment Station. 相似文献
6.
Luis M. Mateos Gustavo del Real Alfredo Aguilar Juán F. Martín 《Molecular & general genetics : MGG》1987,206(3):361-367
Summary Five DNA fragments carrying the thrB gene (homoserine kinase E.C. 2.7.1.39) of Brevibacterium lactofermentum were cloned by complementation of Escherichia coli thrB mutants using pBR322 as vector. All the cloned fragments contained a common 3.1 kb DNA sequence. The cloned fragments hybridized among themselves and with a 9 kb BamHI fragment of the chromosomal DNA of B. lactofermentum but not with the DNA of E. coli. None of the cloned fragments were able to complement thrA and thrC mutations of E. coli. Plasmids pULTH2, pULTH8 and pULTH11 had the cloned DNA fragments in the same orientation and were very stable. On the contrary, plasmid pULTH18 was very unstable and showed the DNA inserted in the opposite direction. E. coli minicells transformed with plasmids pULTH8 or pULTH11 (both carrying the common 3.1 kb fragment) synthesize a protein with an M
r of 30,000 that is similar in size to the homoserine kinase of E. coli.Abbreviations SSC
0.15 M NaCl, 0.015 M sodium citrate
- SDS
sodium dodecyl sulphate
- TSB
tripticase soy broth
- m-DAP
meso-diaminopimelic acid
- Smr, Cpr, Kmr, Amr, Apr, Tcr, MA15r
resistance to streptomycin, cephalotin, kanamycin, amykacin, ampicillin, tetracycline and microcin A 15, respectively 相似文献
7.
Nina V Prokazova Irina A Mikhailenko Sergey N Preobrazhensky Vadim O Ivanov Sergey N Pokrovsky Natalia G Timofeeva Maria A Martinova Vadim S Repin Lev D Bergelson 《Glycoconjugate journal》1986,3(3):273-286
The role of gangliosides in the reception of low density lipoproteins (LDL) was studied using as targets mouse ascites hepatoma 22a (MAH) cells which bind LDL through a specific high affinity receptor. Low density lipoprotein binding and uptake by MAH cells decreased after brief treatment of the cells with neuraminidase to partially remove surface sialic acid residues. The LDL uptake capability of the neuraminidasetreated MAH cells was fully restored after incorporation of exogeneous GM1- and GD1a-gangliosides into the cell surface. In contrast, free (extracellular) gangliosides inhibited LDL uptake by native MAH cells. This inhibitory effect was seen at ganglioside concentrations corresponding to the ganglioside content of serum and was most pronounced with gangliosides whose sialic acids were linked to a terminal galactose residue (GM3, GD1a, GT1b) but was smaller or absent with gangliosides whose sialic acids were attached to an internal galactose (GM1, GM2). The binding of gangliosides to LDL was structure and concentration dependent, saturable and trypsin sensitive. The LDL-ganglioside interaction was further investigated by steady state fluorescence spectroscopy. Changes in the LDL fluorescence polarization were observed with as little as 0.01 M concentrations of the gangliosides. The magnitude and nature of the effect depended on the type of ganglioside. We conclude that the LDL surface possesses sites recognizing specific carbohydrate sequences of glycoconjugates and that changes in the cell surface concentrations of sialic acids significantly modulate the LDL uptake. It is postulated that shedding of gangliosides into the blood stream may be a factor involved in regulation of cholesterol homeostasis.Abbreviations MAH
mouse ascites hepatoma 22a
- LDL
low density lipoprotein
- ASM
anthrylvinyl-labeled sphingomyelin [N-12-(9-anthryl-trans-dodecanoyl-sphingosine-1-phosphocholine]
- RITC
rhodamine isothiocyanate. The designation of gangliosides follows the IUPAC-IUB recommendation [1]: GM3, II3NeuAc-LacCer, II3-N-acetylneuraminosyllactosylceramide
- GM2
II3-NeuAc-GgOse3Cer, II3-N-acetylneuraminosylgangliotriaosylceramide
- GM1
II3-NeuAc-GgOse4Cer, II3-N-acetylneuraminosylgangliotetraosylceramide
- GD1a, II3
IV3(NeuAc)2-GgOse4Cer, II3, IV3-di(N-acetylneuraminosyl)gangliotetraosylceramide
- GT1b
II3(NeuAc)2, IV3 NeuAc-GgOse4Cer, II3-di-N-acetylneuraminosyl, IV3-N-acetylneuraminosylgangliotetraosylceramide 相似文献
8.
K. P. Singh R. K. Jaiswal Niranjan Kumar 《World journal of microbiology & biotechnology》2007,23(2):291-294
Summary
Catenaria anguillulae parasitized and killed the eggs and second stage juveniles (J2) of Meloidogyne graminicola under natural conditions. The percentage of infection in eggs was higher than J2 of M.␣graminicola, which ranged between 0–50.3% and 0–18.9% in 2004 and 0–46.6% and 0–21.7% in 2005, respectively. The higher parasitism of
eggs and J2 was recorded from those fields in which plants were severely infected with M. graminicola. The degree of parasitism of eggs and J2 by C. anguillulae varied with severity of root knot disease. The fields with a higher root gall index recorded a higher percentage of infection
in eggs and J2 of M. graminicola. In general, old galls when teased and incubated, recorded higher parasitism of eggs and juveniles than young galls. 相似文献
9.
DNA of eight endosymbiotic dinoflagellates (zooxanthellae) from seven different host species has been analyzed as to its thermal characteristics and base composition by means of spectrophotometry and high performance liquid chromatography. All algae under investigation contain both methylcytosine and hydroxymethyluracil in addition to the bases typical of nuclear DNA. As a result, melting temperatures are decreased, suggesting lower contents of guanine plus cytosine than actually present. True percentages of guanine plus cytosine plus methylcytosine range from about 43 to 54 mol%. They are unique for the symbionts from different hosts, indicating phylogenetic separation of the taxa comparised within the genus Symbiodinium.Abbreviations dA
deoxyadenosine
- dC
deoxycytidine
- dG
deoxyguanosine
- dT
deoxythymidine
- m5dC
5-methyldeoxycytidine
- hmdU
5-hydroxymethyldeoxyuridine
- rC
ribocytidine
- Br8G
bromine-80guanosine
- A
adenine
- C
cytosine
- G
guanine
- T
thymine
- m5C
5-methylcytosine
- hmU
5-hydroxymethyluracil
- G+C
guanine plus cytosine plus 5-methylcytosine
- HPLC
high performance liquid chromatography
-
T
m
temperature at the midpoint of hyperchromic shift
- CTAB
N-cetyl-N,N,N-trimethyl-ammonium bromide
- EDTA
ethylenediamine-tetraacetic acid, disodium salt
- TRIS
tris-(hydroxymethyl)-aminomethane
- 1×SSC
standard saline citrate (0.15 M NaCl+0.015 M trisodium citrate, pH 7.0) 相似文献
10.
Identification of sulphate-reducing ectosymbiotic bacteria from anaerobic ciliates using 16S rRNA binding oligonucleotide probes 总被引:4,自引:0,他引:4
The identity of ectosymbiotic bacteria of some marine, free-living anacrobic ciliates (Metopus contortus, Caenomorpha levanderi and Parablepharisma sp.) was studied using fluorescent-dye-conjugated oligonucleotides complementary to short sequence elements of 16S ribosomal RNA. The ectosymbiotic bacteria of all species hybridized with a eubacterial probe and those of the two former mentioned species hybridized with a general probe for sulphate-reducing bacteria, but not to a probe specific for Desulfobacter. The results support indirect evidence suggesting that ectosymbiotic bacteria of anaerobic ciliates are sulphate-reducers which depend on host metabolites for substrates.Abbreviations DMSO
dimethyl sulfoxide
- PBS
phosphate-buffered saline, 137 mM NaCl, 2.7 mM KCl, 4.3 mM Na2HPO4, 1.4 mM KH2PO4, pH: 7.3
- TEAA
triethylamonium acetate
- 1 x SSC
standard sodium citrate buffer, 150 mM NaCl, 15 mM Na2 citrate, pH: 7.0
- 1 x Denh
Denhardts solution, 0.02% ficoll, 0.02% bovine serum albumine, 0.02% polyvinol-pyralidone 相似文献
11.
Akira Tanaka Yoshiaki Yamano Hideya Fukuzawa Kanji Ohyama Tohru Komano 《Bioscience, biotechnology, and biochemistry》2013,77(5):1239-1244
Lysate of chloroplasts prepared from liverwort Marchantia polymorpha L. cell suspension cultures incorporated [3H]-dTTP into acid insoluble materials when DNA was added exogenously as a template. The incorporation was highly dependent on the addition of template DNA, four deoxynucleoside triphosphates and magnesium ions (maximum incorporation at 5mM). Magnesium ions could be replaced by manganese ions. DNA synthesis inhibitors, N-ethylmaleimide (NEM) and ethidium bromide (EtBr), strongly inhibited the incorporation. Dideoxythymidine triphosphate (ddTTP), an inhibitor of DNA polymerases β and γ, inhibited the incorporation at the concentration of 50 μM (molar ratio of ddTTP/dTTP = 17). On the other hand, the incorporation by the chloroplast lysate was resistant to arabinofuranosyl cytosine triphosphate (araCTP) and aphidicolin as well as the RNA polymerase inhibitors, rifampicin and α-amanitin. The chloroplast lysate highly utilized denatured calf thymus DNA and bacteriophage ?X174 single-stranded DNA as templates when added exogenously, while a synthetic homopolymer, poly(rA)-oligo(dT)12 ~ 18, did not stimulate the incorporation at all. Autoradiographic analysis of DNA synthesized in isolated chloroplasts showed that the chloroplast DNA synthesis took place at several specific sites on the chloroplast DNA from cells of the liverwort, Marchantia polymorpha. 相似文献
12.
The viability ofMycobacterium leprae, maintained within 33B Schwannoma cells, was estimated in terms of incorporation of [14C] acetate into its specific phenolic glycolipid-1. This measure of viability was correlated with two other assays,viz., fluorescein diacetate/ethidium bromide staining and mouse footpad growth. Observation of a 2-fold increase in the number
of intracellularMycobacterium leprae over an experimental period of 12 days also corroborated this contention. Furthermore, on addition of anti-leprosy drugs
to these intracellularMycobacterium leprae there was significant decrease in phenolic glycolipid-1 synthesis indicative of loss of viability of the organisms. This
study also established the importance of the host cell for active bacillary metabolism, asMycobacterium leprae maintained in cell-free conditions showed no incorporation into phenolic glycolipid-1. Moreover, compromising the host’s
protein synthesis capacity with cycloheximide, also led to reduction in bacillary metabolism. As this system measures the
metabolic synthesis of a uniqueMycobacterium leprae component, it would be useful for development and screening of compounds acting against specific bacillary targets. 相似文献
13.
Time correlated Single Photon Counting study (TCSPC) was performed for the first time to evaluate the effect of resveratrol
(RES) and genistein (GEN) at 10–100 μM and 10–150 μM respectively, in modulating the DNA conformation and the variation induced
due to intercalation by the dyes, ethidium bromide (EtBr) and acridine orange (AO). It is demonstrated using UV-absorption
and fluorescence spectroscopy that RES and GEN, at 50 μM and 100 μM respectively can bind to DNA resulting in significant
de-intercalation of the dyes, preventing their further intercalation within DNA. Hyperchromicity with red/blue shifts in DNA
when bound to dyes was reduced upon addition of RES and GEN. DNA-dependent fluorescence of EtBr and AO was quenched in the
presence of RES by 87.97% and 79.13% respectively, while similar quenching effect was observed for these when interacted with
GEN (85.52% and 83.85%). It is found from TCSPC analysis that the higher lifetime component or constituent of intercalated
dyes (τ2, A
2) decreased with the subsequent increase in smaller component or constituent of free dye (τ1, A
1) after the interaction of drugs with the intercalated DNA. Thus these findings signify that RES and GEN can play an important
role in modulating DNA intercalation, leading to the reduction in DNA-directed toxicity. 相似文献
14.
Annemarie Neuner Holger W. Jannasch Shimshon Belkin Karl. O. Stetter 《Archives of microbiology》1990,153(2):205-207
We describe a new species, Thermococcus litoralis, which is different from the type species Thermococcus celer in molecular, morphological and physiological characteristics.Abbreviations 3 x SSC
(standard saline citrate)
- 0.45 M NaCl
0.045 M Na3-citrate 相似文献
15.
SYNOPSIS. DNA-dependent RNA polymerases have been solubilized from homogenates of Crithidia fasciculata using gentle extraction procedures. RNA polymerase I and II are separated on DEAE cellulose at 0.07M (NH4)2SO4 and 0.13M (NH4)2SO4 respectively. RNA polymerase II is inhibited 80% by α-amanitin (25 μg/ml). Both RNA polymerases require DNA as a template, ribonucleoside triphosphates and Mn2+. The synthesis of RNA as a product is inhibited by DNase. RNase, pronase and actinomycin D. Purified kinetoplast and nuclear DNA can serve as templates for the RNA polymerases. Denatured DNA templates are preferred. The synthesis of RNA continues for at least an hour and is inhibited by trypanocidal drugs including suramin. antrycide, acriflavine, ethidium bromide and berenil. Complementary RNA synthesized in vitro from C. fasciculata kinetoplast DNA hybridizes with C. fasciculata kinetoplast DNA but not with C. fasciculata nuclear DNA or Blastocrithidia culicis kinetoplast DNA, Escherichia coli, T4 or calf thymus DNAs. The complementary RNA synthesized in vitro from C.fasciculata kinetoplast DNA sediments at 4–5S. 相似文献
16.
Conformational transitions in several individual tRNAs (tRNA
inff
supMet
, tRNAPhe from E. coli, tRNA
inf1
supVal
, tRNASer, tRNAPhe from yeast) have been studied under various environmental conditions. The binding isotherms studies for dyes-tRNA complexes exhibited similarities in conformational states of all tRNAs investigated at low ionic strength (0.01 M NaCl). By contrast, at high ionic strength (0.4 M NaCl or 2×10-4 M Mg2+) a marked difference is found in structural features of tRNA
inff
supMet
as compared with other tRNAs used. The tRNA
inff
supMet
is the only tRNA species that does not reveal the strong type of complexes with ethidium bromide, acriflavine and acridine orange. 相似文献
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18.
Alcoholic extract of Plumbago zeylanica (root) was tested against multidrug-resistant clinical isolates of bacteria (Salmonella paratyphi, Staphylococcus aureus, Escherichia coli, Shigella dysenteriae and a R-plasmid-harbouring standard strain, E.coli x+). The extract exhibited strong antibacterial activity against all test bacteria irrespective of their antibiotic resistance
behaviour. Phytochemical analysis of crude extract revealed the presence of flavonoids, saponins and naphthoquinone. A comparative
evaluation of R-plasmid elimination from E. coli x+ (pUK 651) by the plant extract, DNA intercalating dyes (acridine orange and ethidium bromide) and a DNA gyrase antagonizing
drug (pefloxacin) were made. All these agents could cure R-plasmid effectively at their respective sub-MIC concentrations.
Maximum plasmid curing was observed by pefloxacin (88%), followed by ethidium bromide (36%), acridine orange (14%) and alcoholic
extract of P. zeylanica (14%). Curing of plasmid pUK651 from E. coli x+ was confirmed by determining the loss of resistance markers in the cured derivative culture.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
19.
New bis‐macrocyclic complexes of CoIII, 1 , NiII, 2 , and CuII, 3 , containing pyridyl bridges between 13‐membered macrocyclic subunits, have been synthesized via an in situ one‐pot template condensation reaction (IOPTCR). The proposed structures of these new dinuclear complexes are consistent with the data obtained from elemental analysis, molar conductance, IR, EPR, UV/VIS, 1H‐ and 13C‐NMR, and ESI‐MS. The complexes 2 and 3 possess square‐planar geometry with four secondary N‐atoms coordinated to the metal ion, while complex 1 reveals octahedral geometry in solution due to coordinated H2O molecules. DNA‐Binding properties of the complexes 1 and 3 were investigated by absorption and emission titrations, cyclic voltammetry, and viscosity measurements. Complexes 1 and 3 are strong DNA binders with binding constants, Kb, of 1.64×105 and 2.05×105 M ?1, respectively. Hyperchromism, decrease in emission intensity of DNA‐bound ethidium bromide (EB), and changes observed in the viscosity and cyclic voltammograms in the presence of added metal complexes reveals that the complexes bind to DNA predominantly by electrostatic attraction, substantiated by absorption titration with 5′‐GMP. 相似文献
20.
G. Zellner K. Bleicher E. Braun H. Kneifel B. J. Tindall E. Conway de Macario J. Winter 《Archives of microbiology》1988,151(1):1-9
The isolation and characterization of a new methanogen from a peat bog, Methanobacterium palustre spec. nov., strain F, is described. Strain F grew on H2/CO2 and formate in complex medium. It also grew autotrophically on H2/CO2. Furthermore, growth on 2-propanol/CO2 was observed. Methane was formed from CO2 by oxidation of 2-propanol to acetone or 2-butanol to 2-butanone, but growth on 2-butanol plus CO2 apparently was too little to be measurable. Similarly, Methanobacterium bryantii M. o. H. and M. o. H. G formed acetone and 2-butanone from 2-propanol and 2-butanol, but no growth was measurable.On the basis of morphological and biochemical features strain F could be excluded from the genus Methanobrevibacter. Due to its cell morphology, lipid composition and polyamine pattern it belonged to the genus Methanobacterium. From known members of this genus strain F could be distinguished either by a different G+C content of the DNA, low DNA-DNA homology with reference strains, lacking serological reactions with anti-S probes and differences in the substrate spectrum.An alcohol dehydrogenase activity, specific for secondary alcohols and its substrate specificity was determined in crude extracts of strain F. NADP+ was the only electron carrier that was utilized. No reaction was found with NAD+, F420, FMN and FAD.Abbreviations NAD+
nicotinamide adenine dinucleotide
- NADH2
reduced form of NAD+
- NADP+
nicotinamide adenine dinucleotide phosphate
- NADPH2
reduced form of NADP+
- FMN
flavin adenine mononucleotide
- FAD
flavin adenine dinucleotide
- ADH
alcohol dehydrogenase
- F420
8-hydroxy-7,8-didemethyl-5-deazaflavin
- SSC
standard saline citrate (0.15 M NaCl, 0.015 M trisodium citrate, pH 7.5) 相似文献