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101.
Simultaneous high-biomass protein production and nutrient removal using Spirulina maxima in sea water supplemented with anaerobic effluents 总被引:1,自引:0,他引:1
E. J. Olguín B. Hernández A. Araus R. Camacho R. González M. E. Ramírez S. Galicia G. Mercado 《World journal of microbiology & biotechnology》1994,10(5):576-578
Maximum protein accumulation (71%, w/w) and nutrient removal by a mutant strain of Spirulina maxima growing on sea water supplemented with anaerobically treated pig slurry was achieved at 30°C with constant illumination (60 to 70 Em-2s-1), using a flow rate of 14.5 cm s-1 (20 rev. min-1 of a paddle wheel). Total phosphates were decreased by 99% and all ammonia-N was removed under these conditions.The authors are with the Department of Environmental Biotechnology, Institute of Ecology, Aptd Postal 63, Xalapa, Ver., Mexico 相似文献
102.
Enzyme IIBcellobiose of the phosphoenol-pyruvate-dependent phosphotransferase system of Escherichia coli: backbone assignment and secondary structure determined by three-dimensional NMR spectroscopy. 总被引:1,自引:1,他引:0 下载免费PDF全文
E. Ab G. K. Schuurman-Wolters M. H. Saier J. Reizer M. Jacuinod P. Roepstorff K. Dijkstra R. M. Scheek G. T. Robillard 《Protein science : a publication of the Protein Society》1994,3(2):282-290
The assignment of backbone resonances and the secondary structure determination of the Cys 10 Ser mutant of enzyme IIBcellobiose of the Escherichia coli cellobiose-specific phosphoenol-pyruvate-dependent phosphotransferase system are presented. The backbone resonances were assigned using 4 triple resonance experiments, the HNCA and HN(CO)CA experiments, correlating backbone 1H, 15N, and 13C alpha resonances, and the HN(CA)CO and HNCO experiments, correlating backbone 1H,15N and 13CO resonances. Heteronuclear 1H-NOE 1H-15N single quantum coherence (15N-NOESY-HSQC) spectroscopy and heteronuclear 1H total correlation 1H-15N single quantum coherence (15N-TOCSY-HSQC) spectroscopy were used to resolve ambiguities arising from overlapping 13C alpha and 13CO frequencies and to check the assignments from the triple resonance experiments. This procedure, together with a 3-dimensional 1H alpha-13C alpha-13CO experiment (COCAH), yielded the assignment for all observed backbone resonances. The secondary structure was determined using information both from the deviation of observed 1H alpha and 13C alpha chemical shifts from their random coil values and 1H-NOE information from the 15N-NOESY-HSQC. These data show that enzyme IIBcellobiose consists of a 4-stranded parallel beta-sheet and 5 alpha-helices. In the wild-type enzyme IIBcellobiose, the catalytic residue appears to be located at the end of a beta-strand. 相似文献
103.
Takeshi Tabira Jun-ichi Inobe Keiichi Nakahara Mitsuhiro Osame Takashi Yamamura 《Neurochemical research》1994,19(8):1067-1071
To understand the immune mechanism suggested in HTLV-I-associated myelopathy (HAM/TSP), we investigated T cell response to proteolipid protein (PLP). Because of high autologous proliferative response (APR) of peripheral blood mononuclear cells (PBMC) in culture, the lymphocyte proliferation assay was not useful in this disease. Unexpectedly, however, APR was profoundly (70–98%) suppressed in 6 of 9 cases when PLP peptide 105-124 was added in the culture. PLP peptide 85-104 or 145-159 also suppressed APR in a few cases. Time course study showed that the peptide-mediated suppression became apparent after day 4 in culture. The results can be interpreted as that suppressor cells recognizing the PLP peptides were present in the PBMC of HAM/TSP patients and suppressed the APR as the consequence of antigen specific response. This may indicate that a T cell response to certain PLP determinants is involved in the pathomechanism of HAM/TSP at least in part. Molecular mimicry between PLP and HTLV-I mayaccount for the T cell sensitization to PLP in HAM/TSP.Special issue dedicated to Dr. Marjorie B. Lees. 相似文献
104.
105.
Yoshihiko Sawa Ken-ichiro Shibata Mamoru Noda Tsuguo Watanabe 《Microbiology and immunology》1994,38(4):257-262
A 90 kDa protein of Mycoplasma salivarium was released from cell membranes of the organism with Triton X-100 and purified by ion-exchange chromatography and chromatofocusing. The protein was eluted at pH 5.5 by chromatofocusing. The protein was shown to react with the Fc fragments of IgG from human and nine different animal species and did not distinguish between IgG from different species, while protein A, tested for comparative purposes, displayed a strong specificity for human and swine IgG. Furthermore, the protein reacted with antigen specific goat IgG (specific for gamma chains of human IgG), sheep red blood cells (SRBC) sensitized with rabbit antiserum to SRBC, that is, the Fc part of rabbit IgG, and concanavalin A as well. These findings may suggest that the protein is a lectin which binds the carbohydrate moiety of the Fc part of IgG. 相似文献
106.
Twenty-four weanling male Wistar rats were divided into four groups fed diets containing adequate or deficient levels of selenium
(0.5 ppm [+ Se] or <0.02 ppm [−Se] and protein (15% [+Pro] or 5% [−Pro]), but adequate levels of all other nutrients for 4
wk to determine the effects of Se deficiency and protein deficiency on tissue Se and glutathione peroxidase (GSHPx) activity
in rats. Plasma, heart, liver, and kidney Se and GSHPx were significantly lower in Se-deficient groups in relation to Se-sufficient
groups. In Se-deficient groups, Se and GSHPx were significantly higher in −Se−Pro rats in heart, liver, and kidney. Data analysis
showed that there were significant interaction effects between dietary Se and protein on Se and GSHPx of rats. It is assumed
that under the condition of Se deficiency. a low level of protein may decrease Se and GSHPx utilization, increase GSHPx synthesis,
and result in Se redistribution. This could account for high levels of Se and GSHPx in the −Se−Pro rats compared to −Se+Pro
rats. 相似文献
107.
Evaluation of the role of State transitions in determining the efficiency of light utilisation for CO2 assimilation in leaves 总被引:2,自引:0,他引:2
Wheat leaves were exposed to light treatments that excite preferentially Photosystem I (PS I) or Photosystem II (PS II) and induce State 1 or State 2, respectively. Simultaneous measurements of CO2 assimilation, chlorophyll fluorescence and absorbance at 820 nm were used to estimate the quantum efficiencies of CO2 assimilation and PS II and PS I photochemistry during State transitions. State transitions were found to be associated with changes in the efficiency with which an absorbed photon is transferred to an open PS II reaction centre, but did not correlate with changes in the quantum efficiencies of PS II photochemistry or CO2 assimilation. Studies of the phosphorylation status of the light harvesting chlorophyll protein complex associated with PS II (LHC II) in wheat leaves and using chlorina mutants of barley which are deficient in this complex demonstrate that the changes in the effective antennae size of Photosystem II occurring during State transitions require LHC II and correlate with the phosphorylation status of LHC II. However, such correlations were not found in maize leaves. It is concluded that State transitions in C3 leaves are associated with phosphorylation-induced modifications of the PS II antennae, but these changes do not serve to optimise the use of light absorbed by the leaf for CO2 assimilation.Abbreviations Fm, Fo, Fv
maximal, minimal and variable fluorescence yields
- Fm, Fv
maximal and variable fluorescence yields in a light adapted state
- LHC II
light harvesting chlorophyll a/b protein complex associated with PS II
- qP
photochemical quenching
- A820
light-induced absorbance change at 820 nm
- PS I, PS II
relative quantum efficiencies of PS I and PS II photochemistry
- CO
2
quantum yield of CO2 assimilation 相似文献
108.
Methenamine-Silver Staining: a Simple and Sensitive Staining Method for Senile Plaques and Neurofibrillary Tangles 总被引:1,自引:0,他引:1
Chie Haga Kenji Ikeda Kiyoshi Iwabuchi Haruhiko Akiyama Hiromi Kondoh Kenji Kosaka 《Biotechnic & histochemistry》1994,69(5):295-300
An improved methenamine-silver impregnation method is presented which exhibits sensitivity for amyloid substances comparable to that of anti-β protein immunostaining. In optimally treated sections, this technique stained both β-amyloid deposits and neurofibrillary tangles, which are known to have a β-pleated structure. This simple procedure allows a large number of sections to be stained for routine examination. 相似文献
109.
K. Pomeroy D. C. W. Brown Y. Takahata 《In vitro cellular & developmental biology. Plant》1994,30(4):196-203
Summary Microspore-derived embryos fromBrassica napus cv. Topas (low erucic acid) and Reston (high erucic acid) were subjected to treatment with abscisic acid (ABA) during late-stage
embryo development and then dried under controlled relative humidities to mature dry seed levels of moisture. Exogenously
medium-supplied ABA arrested growth and development, reduced moisture content, increased total fatty acids on a dry weight
basis, and stimulated systhesis of proteins in microspore-derived embryos. ABA also resulted in a higher proportion of 22∶1
in cv. Reston (high 22∶1) and increased the level of fatty acid unsaturation in cv. Topas (low 22∶1). The accumulation of
two proteins that co-migrated with cruciferin and napin on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional
gels were also promoted by exposure to ABA, and the degree of accumulation was dependent on the concentration and time of
application of ABA. Controlled desiccation of microspore embryos, used to simulate normal maturation and dehydration of zygotic
embryos during seed development, did not seem to cause an increase of either storage proteins, total fatty acids, or 22∶1
(in cv. Reston), suggesting that dehydration is not a prerequisite for these processes, at least in culturedBrassica embryos. 相似文献
110.
Graeme Milligan 《Journal of neurochemistry》1993,61(3):845-851
Abstract: Levels of the guanine nucleotide binding proteins G11α and Gqα, which produce receptor regulation of phosphoinositidase C., were measured immunologically in 13 regions of rat central nervous system. This was achieved by immunoblotting membranes from these regions with antisera (CQ series) that identify these two polypeptides equally, following separation of the membranes using sodium dodecyl sulphate-polyacrylamide gel electrophoresis conditions that can resolve Gqα and G11α. In all regions examined, Gqα was more highly expressed than G11α. Ratios of levels of Gqα to G11α varied between the regions from 5:1 to 2:1. Quantitative measurements of the levels of Gqα and G11α in each region were obtained by comparison with known amounts of purified liver Gqα and G11α and with E. coli expressed recombinant Gqα. Areas that expressed Gqα highly included olfactory bulb (930 ng/ mg of membrane protein), frontal cortex (700 ng/mg of membrane protein), parietal occipital cortex (670 ng/mg of membrane protein), caudate putamen (1,003 ng/mg of membrane protein), hippocampus (1,045 ng/mg of membrane protein), hypothalamus (790 ng/mg of membrane protein), and cerebellum (950 ng/mg of membrane protein). More modest levels were observed in thalamus (450 ng/mg of membrane protein), pituitary (480 ng/mg of membrane protein), optic chiasma (330 ng/mg of membrane protein), and spinal cord (350 ng/mg of membrane protein). Gna was more evenly expressed with values ranging from about 170 ng/mg of membrane protein in spinal cord and optic chiasma to close to 300 ng/mg of membrane protein in regions expressing high levels of Gqα. A third polypeptide could be identified by the CQ antisera in all brain regions. The possibility that this polypeptide is the α subunit of G14 is discussed. 相似文献