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2.
Tuula Torkkeli Tom Krusius Olli Jnne 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,544(3):578-592
Previous studies have shown that several rabbit tissues contain proteins which cross-react in the radioimmunoassay for uteroglobin, a progestin-regulated protein in rabbit uterus (Torkkeli et al. (1977) Mol. Cell. Endocrinol. 9, 101–118). In the present study, a uteroglobin-like protein was purified to an apparent homogeneity from an extra-uterine tissue, rabbit lung, by successive chromatographies on hydroxyapatite, Sephadex G-75, SP-Sephadex, DEAE-cellulose and CM-cellulose. The final preparation behaved homogeneously in various polyacrylamide gel electrophoretic systems and in isoelectric focusing. The uteroglobin-like protein isolated from the lung had very similar physico-chemical and immunological properties to those of uteroglobin present in the rabbit uterine fluid. The two proteins had: (i) the same molecular weight, of approx. 13 000, with a two subunit structure (each approx. Mr 7000); (ii) identical behavior in polyacrylamide gel electrophoresis under non-denaturing and denaturing conditions; (iii) the same isoelectric point at pH 5.4; (iv) absence of carbohydrate in the molecule; (v) very similar amino acid compositions; (vi) lack of tryptophan among the amino acids; (vii) the same N-terminal amino acid (glycine), and (viii) indistinguishable immunological characteristics. Collectively, these data strongly suggest that uterine and lung uteroglobins are identical proteins.In contrast to the induction of the uterine uteroglobin by steroids with progestational activity, the synthesis of extra-uterine uteroglobins was not affected by these steroid hormones to any major extent. In keeping with the concept that lung is a target tissue for glucocorticoid action, cortisol and dexamethasone were capable of increasing the concentration of lung uteroglobin 3-fold (from 3 to 9 μg/mg soluble protein). These compounds did not, however, alter the secretion of the uterine protein. Administration of high doses of testosterone and 5α-dihydrotestosterone elevated significantly the content of both uterine and lung uteroglobin. Only approx. one-fifth of the adult pulmonary uteroglobin levels were present in lungs of newborn rabbits indicating that developmental changes occur in the lung uteroglobin content. 相似文献
3.
The reputedly obligately organotrophic Thiobacillus ferrooxidans KG-4 cultured on glucose contained a small proportion of cells which grew autotrophically on ferrous-iron. 相似文献
4.
The stoichiometric oxidation of uranous-to uranyl-uranium byThiobacllus ferrooxidans is demonstrated. Fixation of14CO2 and the effect of inhibitors demonstrate that energy is conserved during the oxidation and used for energy-dependent reverse electron flow and carbon dioxide fixation.Abbreviations HOQNO
2-heptyl-4-hydroxyquinoline-N-oxide
- 8-HQ
8-hydroxyquinoline
- TTFA
thenoyltrifluoroacetone 相似文献
5.
Hormonal control of uteroglobin secretion in rabbit uterus. Inhibition of uteroglobin synthesis and messenger ribonucleic acid accumulation by oestrogen and anti-oestrogen administration 下载免费PDF全文
Helena T. Kopu Seija M. Hemminki Tuula K. Torkkeli Olli A. J?nne 《The Biochemical journal》1979,180(3):491-500
Investigations were conducted to quantify activity of uteroglobin mRNA and secretion of uteroglobin in rabbit uterus after administration of progesterone and 5alpha-dihydrotestosterone, either alone or concomitantly with oestradiol-17beta and tamoxifen, a non-steroidal anti-oestrogen. Poly(A)-containing mRNA was isolated from the uterine tissue by extraction with phenol/chloroform, precipitation with ethanol and chromatography on oligo(dT)-cellulose. Cell-free translation in vitro of the poly(A)-containing mRNA was carried out in a wheat-germ lysate, and the product isolated by specific immuno-precipitation with anti-uteroglobin antiserum purified by affinity chromatography. Radioimmunoassay was utilized to determine uteroglobin content in the uterine flushings and tissue preparations. When given for 5 days, both progesterone (1mg/kg per day) and 5alpha-dihydrotestosterone (25mg/kg per day) elicited a marked induction of uteroglobin secretion, which was accompanied with accumulation of uteroglobin mRNA in the tissue. Concomitant administration of oestradiol-17beta (50mug/kg per day) or tamoxifen (12.5mg/kg per day) significantly decreased both progesterone- and 5alpha-dihydrotestosterone-induced uteroglobin secretion, with a parallel decrease in the uteroglobin-mRNA activity. The decline in the uteroglobin content of the uterine flushes brought about by oestradiol-17beta or tamoxifen administration was not due to inhibition of secretion of this protein by the endometrial cells, since a simultaneous decrease occurred in the tissue uteroglobin content. After a 5-day pretreatment with progesterone (1mg/kg per day), administration of oestradiol-17beta (50mug/kg per day) during the ensuing 4 days greatly accelerated the decay of the uteroglobin content in the uterine fluid. 相似文献
6.
Chlorophyll fluorescence induction curves of toxic and non-toxic strains of the cyanobacterium Nodularia were measured and compared with fluorescence curves measured from four species of eukaryotic algae. Both cyanobacteria and algae were isolated from the Baltic Sea. The results show that Nodularia strains can be distinguished from the eukaryotes by applying a pattern recognition procedure to the fluorescence induction curves, suggesting that the fluorescence fingerprinting technique might be useful in environmental monitoring of marine algae. The six studied Nodularia strains could not be distinguished from each other from their fluorescence induction kinetics. However, their fluorescence curves fell into two clear categories, the toxic and the non-toxic Nodularia. Emission spectroscopy and differences in the fluorescence induction curves showed that the ratio of the intensity of the Photosystem I emission peak to the Photosystem II peak is higher in non-toxic Nodularia than in the toxic strains, suggesting that the toxicity affects the structure of the photosynthesis machinery. The effect on photosynthesis may be related to the ability of the microcystins to chelate iron. 相似文献
7.
Liisa Carlson E. Brje Lindstrm Kevin B. Hallberg Olli H. Tuovinen 《Applied microbiology》1992,58(3):1046-1049
Bacterial leaching of an As-containing pyrite concentrate produced acidic (pH < 1) leachates. During the leaching, the bacteria solubilized both As and Fe, and these two elements were distributed in solution-phase and solid-phase products. Jarosite and scorodite were the exclusive crystalline products in precipitate samples from the bacterial leaching of the sulfide concentrate. 相似文献
8.
Assessment of the Microbial Community in a Constructed Wetland that Receives Acid Coal Mine Drainage 总被引:8,自引:0,他引:8
Constructed wetlands are used to treat acid drainage from surface or underground coal mines. However, little is known about
the microbial communities in the receiving wetland cells. The purpose of this work was to characterize the microbial population
present in a wetland that was receiving acid coal mine drainage (AMD). Samples were collected from the oxic sediment zone
of a constructed wetland cell in southeastern Ohio that was treating acid drainage from an underground coal mine seep. Samples
comprised Fe(III) precipitates and were pretreated with ammonium oxalate to remove interfering iron, and the DNA was extracted
and purified by agarose gel electrophoresis prior to amplification of portions of the 16S rRNA gene. Amplified products were
separated by denaturing gradient gel electrophoresis and DNA from seven distinct bands was excised from the gel and sequenced.
The sequences were matched to sequences in the GenBank bacterial 16S rDNA database. The DNA in two of the bands yielded matches
with Acidithiobacillus ferrooxidans and the DNA in each of the remaining five bands was consistent with one of the following microorganisms: Acidithiobacillus thiooxidans, strain TRA3-20 (a eubacterium), strain BEN-4 (an arsenite-oxidizing bacterium), an Alcaligenes sp., and a Bordetella sp. Low bacterial diversity in these samples reflects the highly inorganic nature of the oxic sediment layer where high abundance
of iron- and sulfur-oxidizing bacteria would be expected. The results we obtained by molecular methods supported our findings,
obtained using culture methods, that the dominant microbial species in an acid receiving, oxic wetland are A. thiooxidans and A. ferrooxidans. 相似文献
9.
Summary The carotid bifurcation areas of 25 human fetuses aged from 8 to 22 weeks were studied using the formaldehyde-induced fluorescence method. A long process from the sympathetic trunk reached the area at the age of 8 weeks contacting with the carotid body primordium. Brightly fluorescent cells can be seen both in the carotid body and in the ganglionic process. Migration of these cells from the sympathetic trunk to the carotid body is suggested. The connection from the sympathetic trunk to the carotid body totally disappeared after the tenth week, leaving no fluorescent elements between these two. Control electron microscopy and light microscopy were performed to identify the fluorescent and nonfluorescent components of the human fetal carotid body. 相似文献
10.
Photosynthesis Research - Most photosynthetic organisms are sensitive to very high light, although acclimation mechanisms enable them to deal with exposure to strong light up to a point. Here we... 相似文献