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mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species 总被引:4,自引:0,他引:4
Reconstructions of the human-African great ape phylogeny by using
mitochondrial DNA (mtDNA) have been subject to considerable debate. One
confounding factor may be the lack of data on intraspecific variation. To
test this hypothesis, we examined the effect of intraspecific mtDNA
diversity on the phylogenetic reconstruction of another Plio- Pleistocene
radiation of higher primates, the fascicularis group of macaque (Macaca)
monkey species. Fifteen endonucleases were used to identify 10 haplotypes
of 40-47 restriction sites in M. mulatta, which were compared with similar
data for the other members of this species group. Interpopulational,
intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of
divergence time and branching order incorporating this variation were
substantially different from those based on single representatives of each
species. We conclude that intraspecific mtDNA diversity is substantial in
at least some primate species. Consequently, without prior information on
the extent of genetic diversity within a particular species, intraspecific
variation must be assessed and accounted for when reconstructing primate
phylogenies. Further, we question the reliability of hominoid mtDNA
phylogenies, based as they are on one or a few representatives of each
species, in an already depauperate superfamily of primates.
相似文献
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The Mg,ATP-dependent serine proteinase (Mr = 50 kD; pH optimum 8.0) was isolated and purified 750-fold. The substrate specificity of the enzyme to some protein substrates (catalase, aldolase, uratoxidase, superoxide dismutase, albumin, cytochrome c, insulin) was investigated. The proteinase shows an affinity for proteins whose molecular mass is more than 100 kD. Some quantitative parameters of the enzyme metabolism, e.g., rate constants for synthesis and degradation of serine proteinase and the time of functioning of the de novo synthesized protein, were investigated. 相似文献
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I. Yu. Strelkova S. A. Abdullaev G. P. Snigireva V. G. Bezlepkin A. I. Gaziev 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2011,5(1):88-93
Quantitative and qualitative changes in circulating extracellular DNA (ec-DNA) of blood plasma are considered as markers for
diagnosis and prognosis of tumor pathology. We have investigated the content of mutant copies of the circulating mitochondrial
DNA (ec-mtDNA) in blood plasma in 8 patients with lung cancer before and after radiotherapy as well as in healthy young and
elderly donors. It was found that in plasma of healthy elderly donors the proportion of ec-mtDNA with mutations (in the total
circulating DNA) is much higher than in young donors. Before radiotherapy the proportion of ec-mtDNA with mutations was higher
in plasma of lung cancer patients (aged 70–76 years) than that of healthy elderly donors. After radiotherapy of lung cancer
patients a twofold increase in the proportion of ec-mtDNA with mutations was observed in total circulating plasma DNA. This
may be attributed to release of mutant DNA copies from dying tumor cells and also from normal cells injured by the radiation
treatment. 相似文献
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M V Strelkova 《Parazitologiia》1975,9(6):532-534
The development of the infection process during cutaneous leishmaniosis was traced in one midday gerbil (Meriones meridianus Pall). The gerbil fell ill with cutaneous leishmaniosis after the feeding of san flies of Phlebotomus papatasi and Ph. mongolensis on it. The incubation process of the disease was less than 23 days. Leishmaniosic process began at the base of the concha auriculae and caused the destruction of ear tissues. The complete recover set in 67 days after the infection. Thus, the insignificant duration of the disease does not allow leishmaniae to be preserved in midday gerbils from one season to another. 相似文献
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Jane L Wagstaff Jonathan N Pruneda Stefan MV Freund David Komander 《The EMBO journal》2017,36(24):3555-3572
The Ser/Thr protein kinase PINK1 phosphorylates the well‐folded, globular protein ubiquitin (Ub) at a relatively protected site, Ser65. We previously showed that Ser65 phosphorylation results in a conformational change in which Ub adopts a dynamic equilibrium between the known, common Ub conformation and a distinct, second conformation wherein the last β‐strand is retracted to extend the Ser65 loop and shorten the C‐terminal tail. We show using chemical exchange saturation transfer (CEST) nuclear magnetic resonance experiments that a similar, C‐terminally retracted (Ub‐CR) conformation also exists at low population in wild‐type Ub. Point mutations in the moving β5 and neighbouring β‐strands shift the Ub/Ub‐CR equilibrium. This enabled functional studies of the two states, and we show that while the Ub‐CR conformation is defective for conjugation, it demonstrates improved binding to PINK1 through its extended Ser65 loop, and is a superior PINK1 substrate. Together our data suggest that PINK1 utilises a lowly populated yet more suitable Ub‐CR conformation of Ub for efficient phosphorylation. Our findings could be relevant for many kinases that phosphorylate residues in folded protein domains. 相似文献
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A.?E.?IvanovaEmail author I.?A.?Borzenkov E.?A.?Strelkova Nguen?Thu?Hoai Do?Ngok?Lan S.?S.?Belyaev V.?A.?Karpov 《Microbiology》2012,81(2):233-243
The dominant species and abundance of the cultured aerobic organotrophic bacteria were determined in the clean soils of the
Republic of Vietnam. The total number of organotrophs varied from 2.0 × 105 to 5.8 × 108 CFU/g soil. A considerable fraction of the bacterial population (1.1 × 105–9.5 × 106 CFU/g soil) was able to utilize petroleum hydrocarbons as the sole carbon and energy source. Most of the organisms obtained
in pure cultures were gram-positive bacteria; over 70% were hydrocarbon-oxidizing organisms. Analysis of 16S rRNA gene sequences
resulted in tentative determination of the taxonomic position of 22 strains, with 12 belonging to the Firmicutes, 4, to the Proteobacteria, and 6 to the Actinobacteria. The most common bacteria capable of hydrocarbon oxidation belonged to the genera Acinetobacter, Bacillus, Brevibacillus, Chromobacterium, Cupriavidus, Gordonia, Microbacterium, Mycobacterium, and Rhodococcus. Some of the isolated Bacillus and Staphylococcus strains, as well as one Pseudomonas and one Sinomonas strain, did not utilize hydrocarbons. Gram-positive degraders, especially members of the order Actinomycetales, which exhibited high hydrocarbon-oxidizing activity, gained competitive advantage in the presence of hydrocarbons. This
microbial group probably plays an important role in hydrocarbon degradation in tropical soils. Thus, Vietnamese soils, which
had no history of petroleum contamination, support numerically significant and taxonomically diverse populations of h ydrocarbon-oxidizing
bacteria. 相似文献
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N. V. Kirillova A. I. Spasenkov O. M. Spasenkova M. A. Strelkova 《Applied Biochemistry and Microbiology》2009,45(3):262-265
The content of nucleic acids in the cell culture of fern-leaf aralia Polyscias filicifolia (Moore ex Fournter) Bailey (Araliaceae) exposed to heat shock (3 h at 45°C) decreased significantly (by 20–30%). The decrease in DNA and RNA contents was even larger (30–40%) after longer heat shock (24 h). Cold (24 h at 7°C) caused an even more dramatic decrease in DNA (by 34.2%) and total RNA (by 48%) contents. To judge from the DNA production rate, the presence of hydrogen peroxide and phenazine methosulfate in the culture exerted a dose-dependent and differently directed action on cell proliferation. 相似文献