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1.
2.
The purpose of this study was to examine the possibility of separation and quantification of serum alkaline phosphatase (ALP) isozymes in rats by wheatgerm lectin affinity electrophoresis. Cellulose acetate electrophoresis of the liver and bone ALPs without lectin results in overlapping bands, but in the presence of lectin, the mobility of the band of bone enzyme was retarded and well separated from the liver enzyme band. With this affinity electrophoretic method, we determined the serum ALP isozymes in fed and fasting rats grouped by age. As a result, the absolute activity of bone isozyme showed a downward trend with age in the fed and fasting rats. The serum ALP activity was steadily higher in fed rats than in fasting rats, and the increase was due to intestinal ALP isozyme. There was low activity bordering complete absence in liver isozyme under both nutritional conditions. The affinity electrophoretic method provided a rapid, reproducible, and relatively simple technique for further clinical characterization of ALP isozyme in the rat serum.  相似文献   
3.
Root elongation of Alaska pea seedling was suppressed by higherconcentrations of growth retardants, CCC and ancymidol, thanthose required for shoot elongation. Gibberellic acid (GA3)led to recovery of ancymidol-inhibited elongation, with theconcentration (1 nM) required for roots being lower than thatfor shoots (10 µM). Ancymidol caused swelling of corticalcells in the elongating zone of the root, while GA3 completelycanceled this. These results suggest that roots require muchless gibberellin than shoots for normal elongation growth. Growth kinetics recorded by a computer-regulated rhizometerindicated that the lag periods for growth suppression by ancymidoland growth recovery by GA3 were about 10 h and 7 h, respectively. The composition of the cell wall sugars changed remarkably alongthe root axis from the tip to the base. The arabinose contentwas highest in the tip and rapidly decreased toward the base,whereas galactose complementarily increased toward the base.The thickened zone of ancymidol-treated roots had a higher galactosecontent than GA3-treated slender roots. Other neutral sugarswere not significantly influenced by ancymidol and/or GA3. Theseresults suggest that ancymidol makes cells short and thick withgalactose-rich cell walls while GA3 keeps cells extensible andslender with galactose-poor cell walls. (Received March 3, 1987; Accepted December 4, 1987)  相似文献   
4.
From dilution series in defined mineral medium, a marine iregular coccoid methanogenic bacterium (strain MTP4) was isolated that was able to grow on methanethiol as sole source of energy. The strain also grew on dimethylsulfide, mono-, di-, and trimethylamine, methanol and acetate. On formate the organism produced methane without significant growth. Optimal growth on MT, with doubling times of about 20 h, occurred at 30°C in marine medium. The isolate required p-aminobenzoate and a further not identified vitamin. Strain MTP4 had a high tolerance to hydrogen sulfide but was very sensitive to mechanical forces or addition of detergents such as Triton X-100 or sodium dodecylsulfate. Methanethiol was fermented by strain MTP4 according to the following equation:
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5.
1. CD spectra showed that the fowl protamine, galline, has an unordered structure rich in reverse turns in neutral solution. Eight reverse turns were predicted to be present in the galline molecule on the basis of its amino acid sequence. Spectrophotometric analyses revealed that galline efficiently bound to DNA in 0.25 mM EDTA/10 mM Tricine-HCl, pH 7.4, but hardly so in 30 mM NaCl/3 mM sodium citrate, pH 7.0. Citrate ions bound specifically to the galline molecule, causing a conformational change in it. As a result, galline could not interact with DNA. 2. The concentration of unbound galline in a mixture of DNA and galline in 100 mM NaCl/50 mM Tricine-HCl, pH 7.4, at 37 C was determined by measurement of the intrinsic fluorescence of tyrosine residues of galline in the supernatant after ultracentrifugation of the mixture. The Scatchard plot showed positive co-operativity in the binding of galline to DNA and the binding parameters were determined: the co-operative binding constant (Kc) = 3.3 X 10(7)M-1, the co-operativity factor (q) = 800, and the number of nucleotides of DNA occupied by one galline molecule (n) = 28. The Kc and q values were intermediate between those for clupeine Z from herring sperm and S-methyl protamine from boar sperm. That is, the binding constants of protamine as to DNA decrease in the order of herring, fowl, and boar, while the co-operativities in binding increase in that order.  相似文献   
6.
The complete oxidation of methylmercaptan (MSH) and dimethyl sulfide (DMS) with sulfate or nitrate as electron acceptors was observed in enrichment cultures and dilution series using thermophilic fermentor sludge as the inoculum. Three new strains of thermophilic sulfate reducers were isolated in pure culture (strains MTS5, TDS2, and SDN4). Strain MTS5 grew on MSH and strain TDS2 grew on DMS whereas strain SDN4 grew on either MSH or DMS. The cellular growth yields were 2.57 g (dry weight)/mol of MSH for strain MTS5 and 6.02 g (dry weight)/mol of DMS for strain TDS2. All strains used sulfate, sulfite, or thiosulfate as electron acceptors, but only strain SDN4 used nitrate. DMS and MSH were oxidized to CO2 and sulfide with either sulfate or nitrate as the electron acceptor. Sulfate was stoichiometrically reduced to sulfide while nitrate was reduced to ammonium. All strains were motile rods, required biotin for growth, lacked desulfoviridin, had DNA with G+C contents of 48 to 57 mol% and probably belonged to the genus Desulfotomaculum. This is the first report of the oxidation of MSH and DMS by pure cultures of sulfate-reducing bacteria.  相似文献   
7.
Non-protein-bound iron in human synovial fluid was determined using high-performance liquid chromatography with electrochemical detection. The procedure was based on the separation of the iron—diethylenetriaminepentaacetic acid (DPTA) complex formed directly on a chromatographic column containing an anion-exchange resin followed by electrochemical detection. The method enabled more than 0.1 μM Fe(III) to be determined with an injection volume of 10 μl. A mixture of synovial fluid, 20 μM DTPA and acetate buffer was incubated in the presence and absence of superoxide (O2) generated by a xanthine—xanthine oxidase system and was ultrafiltered through a 30 000 molecular mass cut-off filter. No iron was detected in the ultrafiltrate at physiological pH. However, the presence of iron was observed in the ultrafiltrate at low pH, and O2 and decreased pH, iron may be released into the synovial fluid.  相似文献   
8.
pAD1, a conjugative, 60-kb, hemolysin-bacteriocin plasmid in Enterococcus faecalis, encodes a mating response to a small peptide sex pheromone, cAD1, secreted by potential recipient bacteria. A gene, traC, encoding a 60.7-kDa protein with a typical amino terminal signal peptide, was identified within a region that appears to encode a product that binds to exogenous pheromone. A cloned segment of DNA containing traC resulted in specific binding of cells to synthetic cAD1. The putative traC product has strong similarity to a product of the E. faecalis plasmid pCF10 as well as oligopeptide binding proteins of Escherichia coli, Salmonella typhimurium, and Bacillus subtilis.  相似文献   
9.
Seed dispersal and early revegetation processes were studied in an area devastated by a debris avalanche that occurred on volcano Ontake, Central Japan in 1984. The avalanche was initiated by a volcanic earthquake, and a 3.4 x 107 m3 land mass destroyed the vegetation over 700 ha. The revegetation of the first five years was slow in the area of higher elevation (subalpine area). Both the speed of revegetation and the species richness of trapped seeds varied with the elevation. The post-disturbance vegetation on the deposit with surface soil or plant fragments was richer in species than that without any surface soil. Almost all of the seeds caught by sticky traps and most of the species with frequent occurrence in the vegetation after disturbance were wind dispersed. Wind dispersal was especially important on the deposit without surface soil or plant fragments.  相似文献   
10.
Summary Germination ofBacillus subtilis spores was initiated by L-Ala and competitively inhibited by D-Ala, suggesting the presence of an alanine receptor. The spores showed alanine racemase activity in the spore coat. To investigate the role of alanine racemase (L D) on germination, net racemase activity was determined using diphenylamine as a germination inhibitor and germination was measured using D-penicillamine as a racemase inhibitor. Apparent affinity of L-Ala to the germinant receptor was more than 1000 times higher than that to the racemase. Germination increased in the presence of D-penicillamine, when the concentration of L-Ala was low and that of spores was high. Racemase activity was optimal at 65°C at pH 9.0 and germination at 43°C at pH 7.2. Under unfavorable growth conditions such as high population of spores in limited nutrients, high temperature and high pH, spore alanine racemase converted the germinant actively to the inhibitor and this conversion may regulate germination for survival of the population.  相似文献   
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