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101.
Yukio Yamagata Atsunori Yamashita Katsuhiko Inomata 《Origins of life and evolution of the biosphere》1980,10(1):47-50
Di-and tri-glycine were synthesized in 1M aqueous solution of glycine by bubbling for 90 hr with oxygen discharged in the path from an oxygen cylinder. The peptides were also produced by an incubation at 37°C of 2M glycine solution prepared with 75% hydrogen peroxide, and the yields were traced for 200 days. The final yields were about 0.25% and 0.01% for di-and tri-glycine, respectively. The solution at 166 days of incubation was applied to a Sephadex G 10 column, and the fractions around the top of the chromatogram were found to increase the intensity of ninhydrin color about 45 times after hydrolysis, indicating an existence of oligo-glycine. The solutions of 1M glycine and 0.5M diglycine prepared with 30% hydrogen peroxide were incubated at 37°C for 38 days, and di-and tetra-glycine were detected in the yields of 0.12% and 0.33%, respectively. 相似文献
102.
Transformation-defective mutants of Rous sarcoma virus with longer sizes of genome RNA and their highly frequent occurrences.
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Transformation-defective (td) mutants with different sizes of genomic RNA were isolated from the Prague strain of Rous sarcoma virus, subgroup C(PR-C). All six td viruses (tdTYPR-C) isolated from a single UV-irradiated stock of PR-C (clone 2 of TYPR-C) had slightly longer RNA than did the ordinary class b RNA of tdB77 and Rous-associated virus-7. td viruses spontaneously segregated in uncloned TYPR-C also contained genomic RNA of a size similar to tdTYPR-C RNA. On the other hand, two td mutants isolated from another stock of PR-C (LAPR-C) had the class b RNA. Fingerprint analysis confirmed that tdTYPR-C and tdLAPR-C were derived by deletion from clone 2 of TYPR-C and LAPR-C, respectively, and also showed that clone 2 of TYPR-C had sequences in its genome RNA different from those of LAPR-C, although it gave a fingerprinting pattern similar to the latter. These results strongly suggest that differences between the nucleotide sequences in TYPR-C and LAPR-C RNA may result in different extents of deletion. 相似文献
103.
Urine of a fucosidosis patient contained a large amount of fucosyl oligosaccharides and fucose-rich glycopeptides. Six major oligosaccharides were purified by a combination of Bio-Gel P-2 and P-4 column chromatographies and paper chromatography. Structural studies by sequential exoglycosidase digestion and by methylation analysis revealed that their structures were as follows: Fucalpha1 leads to 6GlcNAc, Fucalpha1 leads to 2Galbeta1 leads to 4(Fucalpha1 leads to 3)GlcNAcbeta1 leads to 2Manalpha1 leads to 3Manbeta1 leads to 4GlcNAc, Galbeta1 leads to 4(Fucalpha1 leads to 3)GlcNAcbeta1 leads to 4Manalpha1 leads to 4GlcNAc, Galbeta1 leads to 4(Fucalpha1 leads to3)GlcNAcbeta1 leads to 2Manalpha1 leads to 6Manbeta1 leads to 4GlcNAc, and Galbeta1 leads to 4(Fucalpha1 leads to 3)GlcNAcbeta1 leads to 4Manalpha1 leads to 6Manalpha1 leads to 6Manbeta1 leads to 4GlcNAc. In additon, the structure of a minor decasaccharide was found to be Galbeta1 leads to (Fucalpha1 leads to)GlcNAcbeta1 leads to Manalpha1 leads to [Galbeta1 leads to (Fucalpha1 leads to)GlcNAcbeta1 leads to Manalpha1 leads to]Manbeta1 leads to 4GlcNAc. 相似文献
104.
Yamashita Takashi; Inoue Yorinao; Kobayashi Yoshichika; Shibata Kazuo 《Plant & cell physiology》1978,19(5):895-900
The light conditions required for reactivation of the oxygen-evolvingsystem in Tris-treated chloroplasts were studied by means ofrepetitive flashes. Inactive Tristreated chloroplasts were washedwith reduced 2,6-dichlorophenolindophenol, suspended in a reactivationmedium containing Mn2++ and Ca2++ ions, then illuminated withflashes. Flashes at dark intervals of 2 sec were most effectivefor reactivation, while those at shorter or longer intervalswere less effective. It was deduced that more than two sequentiallight reactions with dark reactions in between were involvedin the reactivation. (Received December 28, 1977; ) 相似文献
105.
Kozo Yamamoto Tetsuya Tosa Kiyokazu Yamashita Ichiro Chibata 《Biotechnology and bioengineering》1977,19(8):1101-1114
The kinetics of the reversible fumarase reaction of immobilized Brevibacterium ammoniagenes cells and the decay behavior of enzyme activity were investigated in a plug flow system. The time course of the reaction in the immobilized cell column was well explained by the time-conversion equation including the apparent kinetic constants of the immobilized cell enzyme. The decay rate of fumarase activity was faster in the upper sections of the column (inlet side of the substrate solution) compared with the lower sections when 1M sodium fumarate (pH 7.0) was continuously passed through the column at 37°C. It was shown that the decay rate of the fumarase activity in the immobilized cell column depends on the flow rate of the substrate solution. The effect of flow rate on the decay rate of enzyme activity was considered to be related to the rate of contamination of enzyme with poisonous substances derived from the substrate solution or to the rate of leakage of enzyme stabilizers and/or enzyme itself from the immobilized cells. 相似文献
106.
107.
Yoshiteru Harada Kunio Tanaka Kowa Yamashita Masataka Ishibashi Hiroshi Miyazaki Makoto Katori 《Prostaglandins & other lipid mediators》1983,26(1):79-90
Intrapleural injection of 2% λ-carrageenin caused the accumulation of exudate up to 19 hr. The rate of plasma exudation, measured by the exuded dye amounts for 20 min in the pleural cavity after intravenous injection of pontamine sky blue, showed a peak at 5 hr. Aspirin (100 mg/kg, i. p.) suppressed the dye exudation up to 5 hr, but did not at 7 hr. This inhibition coincided with the decrease of the PG and TXB2 levels, which were measured by gas chromatography-mass spectrometry, in the pleural exudate. In vitro experiments, MK-447, a phenolic compound, stimulates PG endoperoxide biosynthesis at lower doses and inhibits it at higher doses, acting as a tryptophan-like cofactor required by PG endoperoxide synthetase. This drug (0.3, 1.0 and 3.0 mg/kg, i. p.) suppressed the dye exudation dose-dependently up to 5 hr, but did not at 7 hr even at a higher dose, in combination with the dose-dependent decrease of the pleural level of PGE2, which was reported to be a major PG among PGs and TXB2 in the exudate in inducing the plasma exudation (Harada
; Prostaglandins,
: 881, 1982). Thus, the anti-inflammatory action of MK-447 can be explained by inhibition of PGE2 generation, giving no consideration to the role of oxygen-derived free radicals as a prime mediator in inflammation. 相似文献
108.
T Hirai M Yamashita M Yoshikuni Y H Lou Y Nagahama 《Molecular reproduction and development》1992,33(2):131-140
Under the influence of maturation-inducing hormone (MIH) secreted from follicle cells, oocyte maturation is finally triggered by maturation-promoting factor (MPF), which consists of a homolog of the cdc2+ gene product of fission yeast (p34cdc2) and cyclin B. Two species of cyclin B clones were isolated from a cDNA library constructed from mature goldfish oocytes. Sequence comparisons revealed that these two clones are highly homologous (95%) and were found to be similar to Xenopus cyclin B1. Using monoclonal antibodies against Escherichia coli-produced goldfish cyclin B and the PSTAIR sequence of p34cdc2, we examined the levels of cyclin B and p34cdc2 proteins during goldfish oocyte maturation induced in vitro by 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one (17 alpha, 20 beta-DP), a natural MIH in fish. Protein p34cdc2 was found in immature oocyte extracts and did not remarkably change during oocyte maturation. Cyclin B was not detected in immature oocyte extracts and appeared when oocytes underwent germinal vesicle breakdown. Cyclin B that appeared during oocyte maturation was labelled with [35S]methionine, indicating its de novo synthesis. Introduction of E. coli-produced cyclin B into immature oocyte extracts induced p34cdc2 (MPF) activation. Although the possibility that immature goldfish oocytes contain an insoluble cyclin B is not completely excluded, these results strongly suggest that 17 alpha, 20 beta-DP induces oocytes to synthesize cyclin B, which in turn activates preexisting p34cdc2, forming active MPF. 相似文献
109.
K Kawai A Fukamizu Y Kawakami M Matsumura K Mitsui K Murakami K Yamashita 《Endocrinologia japonica》1991,38(6):603-609
A 54-year-old woman was referred to our hospital for the treatment of a tumor of the right chest wall. Clinical examination revealed hypertension, hypokalemia, metabolic alkalosis, hyperaldosteronism and hyperreninemia. Computed tomography and an abdominal echogram indicated a tumor in the right phrenic area and two tumors in the retroperitoneum near the pancreas head. After the surgical resection of these tumors, the primary reninism was diminished. The pathological diagnosis of these tumors was leiomyosarcoma. Plasma active and inactive (trypsin-activated) renin activities (PRA) were 85.7 and 38.9 ng angiotensin I/ml/h, respectively. These PRA did not respond to either postural stimulation or suppression by the volume expansion. Active and inactive renin activities in a right phrenic area tumor were 208 and 32 ng angiotensin I/mg protein /h, respectively. Those of an abdominal tumor were 196 and 30 ng angiotensin I/mg protein/h, respectively. Renin mRNA identical in molecular size to that of the human kidney was identified by northern blot analysis. This is the first case report of renin producing leiomyosarcoma derived from the lung, which is characterized by relatively lower plasma prorenin concentrations. 相似文献
110.
Maturation-promoting factor and a homolog of fission yeast cdc2+ gene product (p34cdc2) were investigated during the final 24 hr of maturation of quail oocytes. Kinase activity of p34cdc2 in the oocyte germinal disk (GD) increased 15 times at maturation. Two bands, at 32 and 34 kDa, were detected in immature oocytes by immunoblotting of SDS-PAGE with anti-p34cdc2 monoclonal antibody. A new band, which is close to the 32-kDa band but with a slightly faster mobility, appeared during maturation. No p34cdc2 could be detected outside the GD. Microinjection of GD extract from mature oocytes caused maturation of Xenopus oocytes. 相似文献