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91.
Physical and genetic structure of the IncN plasmid R15 总被引:1,自引:0,他引:1
Restriction sites for seven hexanucleotide-specific endonucleases were located on the map of the conjugative IncN plasmid R15 (SmrSurHgr, 62.3 kb). The distribution of the cleavage sites is strongly asymmetric. Twenty-eight of thirty-four sites for BamHI, EcoRI, HindIII, SalI, SmaI, and PstI were located close to or within the sequences of an IS5-like element and the transposons Tn2353 and Tn2354. By analysis of R15::Tn1756 deletion derivatives and recombinant plasmids harboring R15 fragments, the genetic determinants for the streptomycin, sulfonamide, and mercury resistances were mapped, as well as the regions necessary for EcoRII restriction-modification and for plasmid replication and conjugation. The features of physical and genetic structures of the plasmid R15 and other IncN plasmids are discussed. 相似文献
92.
Molecular assembly of meiotic proteins Asy1 and Zyp1 and pairing promiscuity in rye (Secale cereale L.) and its synaptic mutant sy10 下载免费PDF全文
Mikhailova EI Phillips D Sosnikhina SP Lovtsyus AV Jones RN Jenkins G 《Genetics》2006,174(3):1247-1258
Assembly of two orthologous proteins associated with meiotic chromosome axes in Arabidopsis thaliana (Asy1 and Zyp1) was studied immunologically at meiotic prophase of meiosis of wild-type rye (Secale cereale) and its synaptic mutant sy10, using antibodies derived from A. thaliana. The temporal and spatial expression of the two proteins were similar in wild-type rye, but with one notable difference. Unlike A. thaliana, in which foci of the transverse filament protein Zyp1 appear to linearize commensurately with synapsis, linear tracts of Asy1 and Zyp1 protein form independently at leptotene and early zygotene of rye and coalign into triple structures resembling synaptonemal complexes (SCs) only at later stages of synapsis. The sy10 mutant used in this study also forms spatially separate linear tracts of Asy1 and Zyp1 proteins at leptotene and early zygotene, and these coalign but do not form regular triple structures at midprophase. Electron microscopy of spread axial elements reveals extensive asynapsis with some exchanges of pairing partners. Indiscriminate SCs support nonhomologous chiasma formation at metaphase I, as revealed by multi-color fluorescence in situ hybridization enabling reliable identification of all the chromosomes of the complement. Scrutiny of chiasmate associations of chromosomes at this stage revealed some specificity in the associations of homologous and nonhomologous chromosomes. Inferences about the nature of synapsis in this mutant were drawn from such observations. 相似文献
93.
A. N. Eryomin T. V. Semashko R. V. Mikhailova 《Applied Biochemistry and Microbiology》2006,42(2):138-144
Different methods of immobilization of extracellular glucose oxidase (GO) from Penicillium funiculosum 46.1 on gels of aluminum or zinc hydroxides have been compared. GO from the culture liquid filtrate (CLF) associated with Zn(OH)2 but not Al(OH)3 gels. Preparation of samples of immobilized GO does not require isolation of the enzyme (CLF may be used). GO immobilized on Zn(OH)2 gels from CLF was 1.6 times more efficient in catalyzing D-glucose oxidation than the enzyme contained in the original culture liquid. Crosslinking of gel-adsorbed CLF proteins affected the properties of GO adversely and to a considerable extent. Various means of polymerization and immobilization of GO isolated from CLF have been studied. Optimum results were obtained when GO polymeric products were pre-synthesized in solution, followed by adsorption to Al(OH)3, but not Zn(OH)2 gels. The catalytic efficiency of GO immobilized on a Zn(OH)2 gel was significantly lower than that of the enzyme associated with Al(OH)3. 相似文献
94.
Surin AM Bolshakov AP Mikhailova MM Sorokina EG Senilova YE Pinelis VG Khodorov BI 《Biochemistry. Biokhimii?a》2006,71(8):864-870
Maturation of primary neuronal cultures is accompanied by an increase in the proportion of cells that exhibit biphasic increase in free cytoplasmic Ca2+ ([Ca2+]i) followed by synchronic decrease in electrical potential difference across the inner mitochondrial membrane (DeltaPsim) in response to stimulation of glutamate receptors. In the present study we have examined whether the appearance of the second phase of [Ca2+]i change can be attributed to arachidonic acid (AA) release in response to the effect of glutamate (Glu) on neurons. Using primary culture of rat cerebellar granule cells we have investigated the effect of AA (1-20 microM) on [Ca2+]i, DeltaPsim, and [ATP] and changes in these parameters induced by neurotoxic concentrations of Glu (100 microM, 10-40 min). At =10 microM, AA caused insignificant decrease in DeltaPsim without any influence on [Ca2+]i. The mitochondrial ATPase inhibitor oligomycin enhanced AA-induced decrease in DeltaPsim; this suggests that AA may inhibit mitochondrial respiration. Addition of AA during the treatment with Glu resulted in more pronounced augmentation of [Ca2+]i and the decrease in DeltaPsim than the changes in these parameters observed during independent action of AA; removal of Glu did not abolish these changes. An inhibitor of the cyclooxygenase and lipoxygenase pathways of AA metabolism, 5,8,11,14-eicosatetraynoic acid, increased the proportion of neurons characterized by Glu-induced biphasic increase in [Ca2+]i and the decrease in DeltaPsim. Palmitic acid (30 microM) did not increase the percentage of neurons exhibiting biphasic response to Glu. Co-administration of AA and Glu caused 2-3 times more pronounced decrease in ATP concentrations than that observed during the independent effect of AA and Glu. The data suggest that AA may influence the functional state of mitochondria, and these changes may promote biphasic [Ca2+]i and DeltaPsim responses of neurons to the neurotoxic effect of Glu. 相似文献
95.
Clum A Nolan M Lang E Glavina Del Rio T Tice H Copeland A Cheng JF Lucas S Chen F Bruce D Goodwin L Pitluck S Ivanova N Mavrommatis K Mikhailova N Pati A Chen A Palaniappan K Göker M Spring S Land M Hauser L Chang YJ Jeffries CC Chain P Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lapidus A 《Standards in genomic sciences》2009,1(1):38-45
Acidimicrobium ferrooxidans (Clark and Norris 1996) is the sole and type species of the genus, which until recently was the only genus within the actinobacterial family Acidimicrobiaceae and in the order Acidomicrobiales. Rapid oxidation of iron pyrite during autotrophic growth in the absence of an enhanced CO(2) concentration is characteristic for A. ferrooxidans. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the order Acidomicrobiales, and the 2,158,157 bp long single replicon genome with its 2038 protein coding and 54 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
96.
Ivanova N Gronow S Lapidus A Copeland A Glavina Del Rio T Nolan M Lucas S Chen F Tice H Cheng JF Saunders E Bruce D Goodwin L Brettin T Detter JC Han C Pitluck S Mikhailova N Pati A Mavrommatis K Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Chain P Rohde C Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2009,1(2):126-132
Leptotrichia buccalis (Robin 1853) Trevisan 1879 is the type species of the genus, and is of phylogenetic interest because of its isolated location in the sparsely populated and neither taxonomically nor genomically adequately accessed family 'Leptotrichiaceae' within the phylum 'Fusobacteria'. Species of Leptotrichia are large, fusiform, non-motile, non-sporulating rods, which often populate the human oral flora. L. buccalis is anaerobic to aerotolerant, and saccharolytic. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first complete genome sequence of the order 'Fusobacteriales' and no more than the second sequence from the phylum 'Fusobacteria'. The 2,465,610 bp long single replicon genome with its 2306 protein-coding and 61 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
97.
Spring S Lapidus A Schröder M Gleim D Sims D Meincke L Glavina Del Rio T Tice H Copeland A Cheng JF Lucas S Chen F Nolan M Bruce D Goodwin L Pitluck S Ivanova N Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Chain P Saunders E Brettin T Detter JC Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Han C 《Standards in genomic sciences》2009,1(3):242-253
Desulfotomaculum acetoxidans Widdel and Pfennig 1977 was one of the first sulfate-reducing bacteria known to grow with acetate as sole energy and carbon source. It is able to oxidize substrates completely to carbon dioxide with sulfate as the electron acceptor, which is reduced to hydrogen sulfide. All available data about this species are based on strain 5575(T), isolated from piggery waste in Germany. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of a Desulfotomaculum species with validly published name. The 4,545,624 bp long single replicon genome with its 4370 protein-coding and 100 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
98.
T. P. Tourova A. V. Korshunova E. M. Mikhailova D. Sh. Sokolova A. B. Poltaraus T. N. Nazina 《Microbiology》2010,79(3):356-369
The primary structures of the genes encoding the β-subunits of a type II topoisomerase (gyrase, gyrB) and a type IV topoisomerase (parE) were determined for 15 strains of thermophilic bacteria of the genus Geobacillus. The obtained sequences were used for analysis of the phylogenetic similarity between members of this genus. Comparison of
the phylogenetic trees of geobacilli constructed on the basis of the 16S rRNA, gyrB, and parE gene sequences demonstrated that the level of genetic distance between the sequences of the genes encoding the β-subunits
of type II topoisomerases significantly exceeded the values obtained by comparative analysis of the 16S rRNA gene sequences
of Geobacillus strains. It was shown that, unlike the 16S rRNA gene analysis, comparative analysis of the gyrB and parE gene sequences provided a more precise determination of the phylogenetic position of bacteria at the species level. The data
obtained suggest the possibility of using the genes encoding the β-subunits of type II topoisomerases as phylogenetic markers
for determination of the species structure of geobacilli. 相似文献
99.
O. V. Nevzglyadova A. V. Artemov A. G. Mittenberg E. V. Mikhailova I. M. Kuznetsova K. K. Turoverov T. R. Soidla 《Cell and Tissue Biology》2010,4(2):152-166
Amyloid-bound thioflavin T fluorescence was studied in lysates of yeast strains that carry mutations in the ADE1 or ADE2 genes and accumulate red pigment as a result of the polymerization of aminoimidazole ribotide (an intermediate of adenine
biosynthesis). The fluorescence is drastically enhanced in cells grown in media with high concentrations of adenine (100 mg/l),
which suppresses the accumulation of red pigment. Mutations that block the first stages of purine biosynthesis de novo also
impede the accumulation of red pigment and produce the same effect on thioflavin fluorescence. Mutations in ADE1 or ADE2 genes in originally white prototrophic strains considerably suppress fluorescence. The fraction of protein polymers was studied
by agarose gel electrophoresis, which permitted us to conclude that reduced fluorescence intensity was associated with decreased
amyloid content in cells that accumulate red pigment. Model experiments with insulin fibers demonstrate that red pigment binds
fibrils and blocks their interaction with thioflavin T. A comparison of lysate pellet proteins from red and white isogenic
strains separated by 2D electrophoresis followed by MALDI analysis allowed us to identify 23 pigment-dependent proteins. These
proteins mostly belong to functional classes of chaperones and proteins involved in glucose metabolism, which closely correspond
to the prion-dependent proteins that we characterized previously. We suppose that the binding of red pigment with amyloid
fibrils prevents the generation of prion aggregates and impedes prion propagation by blocking fibril contact with chaperones. 相似文献
100.
Pilar del Hoyo Alberto García-Redondo Fernando de Bustos José Antonio Molina Youssef Sayed Hortensia Alonso-Navarro Luis Caballero Joaquín Arenas José AG Agúndez Félix Javier Jiménez-Jiménez 《BMC neurology》2010,10(1):95