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51.
Crude extracts of mycelia and basidiocarp primordia in the basidiomycete Coprinus cinereus were resolved on sodium dodecyl sulfate--polyacrylamide gels, and ubiquitin and several proteins were detected by immunoblotting with anti-ubiquitin antibody. The molecular masses of the proteins detected were 30,900, 28,600, 27,800, 26,300, 22,500, and 15,400 daltons, respectively. Relative levels of ubiquitin and most of the ubiquitin-immunoreactive proteins in basidiocarp primordium formation increased and in basidiocarp maturation decreased in cap and upper stipe, while in lower stipe became high except for the 27,800 dalton protein and ubiquitin. During sporulation, ubiquitin and all the ubiquitin-immunoreactive proteins tended to decrease in the cap of the young wild-type basidiocarp. The levels of 30,900 and 15,400 dalton proteins increased transiently at 6-10 h after the beginning of the last light period, while ubiquitin decreased markedly. No correlation was observed between changes in levels of the ubiquitin-immunoreactive proteins and the blocked stages in sporulation-deficient mutants. 相似文献
52.
Anaerobic bacteria degrading 2-methoxyethanol were enriched from freshwater sediments, and three strains were isolated in pure culture. Two of them were Grampositive non-spore-forming rods and grew strictly anaerobically by acetogenic fermentation. Optimal growth occurred at 30°C, initial pH 7.5–8.0. 2-Methoxyethanol and 2-ethoxyethanol were fermented to acetate and corresponding alcohols. Hydrogen plus carbon dioxide, formate, acetoin, l-malate, lactate, pyruvate, fructose, and methoxyl groups of 3,4,5-trimethoxybenzoate and 3,4,5-trimethoxycinnamate were fermented to acetate. 1,2-Propanediol was fermented to acetate, propionate, and propanol. Strain MuME1 was described as a new species, Actetobacterium malicum. It had a DNA base composition of 44.1 mol% guanine plus cytosine. The third strain, which was identified as Pelobacter venetianus, fermented 2-methoxyethanol to methanol, ethanol, and acetate. 相似文献
53.
The complete nucleotide sequence of the gene for batroxobin, a thrombin-like snake venom enzyme. 总被引:1,自引:0,他引:1
N Itoh N Tanaka I Funakoshi T Kawasaki S Mihashi I Yamashina 《Nucleic acids research》1988,16(21):10377-10378
54.
gamma-Aminobutyric acid (GABA) content was measured, and the release of GABA was studied in the synovial membrane of the rat knee joint. GABA content of the synovial membrane was 20.1 nmol/g tissue. Ten days after unilateral dissection of the sciatic nerve, femoral nerve or both nerves, the GABA contents of the ipsilateral membrane were 13.8, 14.6 and 7.8 nmol/g tissue, respectively. High K+ evoked the Ca2+-dependent release of [3H] GABA from the synovial membranes of intact rats preloaded with [3H] GABA, but did not evoke release from the membrane ipsilateral to the dissection of both sciatic and femoral nerves. Evoked release of [3H] GABA was obtained in the synovial membrane preloaded with [3H] GABA in the presence of beta-alanine, but not in the presence of 2,4-L-diaminobutyric acid. These results indicate that GABA is present in the neuronal elements of the synovial membrane of the rat knee joint. 相似文献
55.
Anti-idiotypic antibodies against UV-induced tumor-specific CTL clones. Preparation in syngeneic combination 总被引:2,自引:0,他引:2
K Kuribayashi C Tanaka Y Matsubayashi T Masuda H Udono M Abe E Nakayama H Shiku 《Journal of immunology (Baltimore, Md. : 1950)》1988,141(11):4074-4080
In this study, we first established several CTL clones of (BALB/c x C57BL/6)F1 origin that were specific for either syngeneic UV female 1 or UV male 1 fibrosarcoma cell lines. All the CTL clones had Thy-1+ Lyt-2+ L3T4- phenotypes and showed Kd restriction when lysing the corresponding target cells. Sera obtained from syngeneic animals immunized with three CTL clones, 10B-5 for UV female 1, and CTL9 and CTL10 for UV male 1, showed specific inhibition of target cell lysis with the corresponding CTL clones. The inhibitory activities were found in sera of the majority of immunized animals. Because the inhibitory activity resides in protein A-binding fraction, mAb were produced by hybridizing spleen cells of hyperimmune animals. N1-56 was thus obtained from a mouse immunized with 10B-5 CTL clone reactive with UV female 1. N1-56 was clonotype specific, reacting with 10B-5 but not with other CTL lines or leukemia cell lines. No N1-56+ cells were detectable in thymocytes, lymph node cells, or spleen cells of either naive or UV female 1-immune CB6F1 mice. Immunoprecipitation showed that N1-56 reacts with 90,000 Mr molecules on 10B-5 CTL clone under nonreducing conditions and 45,000 Mr molecules under reducing conditions, indicating its reactivities with idiotypic determinants of TCR on the CTL clone. N1-56 inhibited lytic activity of 10B-5, but neither N1-56 nor alpha-10B-5 hyperimmune serum inhibited that of alpha-UV female 1 mixed lymphocyte tumor cell culture cells. N1-56 induced proliferation of 10B-5 without addition of Ag. 相似文献
56.
Breathing pattern and steady-state CO2 ventilatory response during mouth breathing were compared with those during nose breathing in nine healthy adults. In addition, the effect of warming and humidification of the inspired air on the ventilatory response was observed during breathing through a mouthpiece. We found the following. 1) Dead space and airway resistance were significantly greater during nose than during mouth breathing. 2) The slope of CO2 ventilatory responses did not differ appreciably during the two types of breathing, but CO2 occlusion pressure response was significantly enhanced during nose breathing. 3) Inhalation of warm and humid air through a mouthpiece significantly depressed CO2 ventilation and occlusion pressure responses. These results fit our observation that end-tidal PCO2 was significantly higher during nose than during mouth breathing. It is suggested that a loss of nasal functions, such as during nasal obstruction, may result in lowering of CO2, fostering apneic spells during sleep. 相似文献
57.
The heterogeneity and differential expression of protein kinase C in nervous tissues 总被引:1,自引:0,他引:1
58.
Kiyoshi Akeo Yasuhiko Tanaka Tatsuji Fujiwara 《In vitro cellular & developmental biology. Plant》1988,24(7):705-710
Summary The endocytotic process in cultured human RPE cells was observed after 1 min, 20 min, and 2 h incubation with cationized ferritin.
Within 1 min the ferritin particles were seen to attach to the cell membrane, especially between microvilli. Uncoated and
coated pits could be recognized on the cell membranes, and uncoated and coated endocytotic vesicles were found in the cytoplasm
after 20 min of incubation. These vesicles were surrounded by abundant microfilaments and had no visible membranes. Loss of
membrane may be an initial step in the process of developing into the irregular clumps of ferritin particles found inside
the plasma membrane. With time, more irregular clumps of ferritin, smaller than the particles introduced during incubation,
appeared just beneath the cell membrane. Lysosomes were adjacent to the clumps of ferritin particles associated with microtobules
and finally degraded these particles. The phagolysosomes containing many particles were surrounded by many microtubules. Small
ferritin particles surrounded but had not entered the rough endoplasmic reticulums, and no particles were seen either around
or in the Golgi apparatus.
Presented at the 7th International Congress of Eye Research, Nagoya, Japan, 27 September 1986. 相似文献
59.
cDNA cloning of a novel heterogeneous nuclear ribonucleoprotein gene homologue in Caenorhabditis elegans using hamster prion protein cDNA as a hybridization probe. 下载免费PDF全文
The mammalian prion protein (PrPc) is a cellular protein of unknown function, an altered isoform of which (PrPsc) is a component of the infectious particle (prion) thought to be responsible for spongiform encephalopathies in humans and animals. The evolutionary conservation of the PrP gene has been reported in the genomes of many vertebrates as well as certain invertebrates. In the genome of nematode Caenorhabditis elegans, the sequence capable of hybridizing with the mammalian PrP cDNA probe has been demonstrated, predicting the presence of the PrP gene homologue in C.elegans. In this study, Southern analysis with the hamster PrP cDNA (HaPrP) probe confirmed the previous observation. Moreover, Northern analysis revealed that the sequence is actively transcribed in adult worms. Thus, we screened C.elegans cDNA libraries with the HaPrP probe and isolated a cDNA that hybridizes to the same sequence in C.elegans that hybridized with the HaPrP probe in the Southern and Northern analyses. The deduced amino acid sequence of this cDNA, however, is substantially homologous with heterogeneous nuclear ribonucleoprotein (hnRNP) core proteins rather than mammalian PrPc. The hnRNPs contain the glycine-rich domain in the C-terminal half of the molecule, which also seemed to be in PrPc at the N-terminal half of the molecule. Both of the glycine-rich domains are composed of tracts with high G + C content, indicating that these tracts may due to the hybridizing signals. These results suggest that this cDNA clone is derived from a novel hnRNP gene homologue in C.elegans but not from a predicted PrP gene homologue. 相似文献
60.
T Masaki T Tanaka S Tsunasawa F Sakiyama M Soejima 《Bioscience, biotechnology, and biochemistry》1992,56(10):1604-1607
Z-Val-, Z-Pro-, Z-Leu-Leu-, and Z-Leu-Pro-lysinals and BZ-DL-lysinal were chemically synthesized and tested as novel inhibitors for Achromobacter protease I (API), a lysine-specific serine protease. Among the lysinal derivatives tested, Z-Val-lysinal was the most potent competitive inhibitor, its Ki being estimated as 6.5 nM in an esterolytic assay with Tos-Lys-OMe. In an amidolytic assay, Z-Leu-Leu-lysinal was the most potent inhibitor and the apparent mode of inhibition was non-competitive. The Kis of the other lysinal derivatives in both esterolytic and amidolytic assays were more than 10(3) times lower than that of leupeptin. Z-Val-lysinol, lacking the aldehyde group, was a poor competitive inhibitor. These results suggest that acyl-, acylaminoacyl-, and acylpeptidyllysinals function as a transition-state inhibitor for Achromobacter protease I. 相似文献