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31.
Summary For the protein upgrading of sugar-beet pulp in solid state fermentation byTrichoderma reesei andFusarium oxysporum, serveral conditions were studied to prepare an economical preculture for large scale process. The best performance was shown by a preculture obtained in 24 h from 1.5 % molasses solution at pH 4.5–5.0 with 1.0 % milled beet pulp.  相似文献   
32.
It needs three factors to build an industry: market demand, product vision and capital. White biotechnology already produces high volume products such as feed additive amino acids and specialty products like enzymes for enantioselective biocatalysis. It serves large and diverse markets in the nutrition, wellness, pharmaceutical, agricultural and chemical industry. The total volume adds up to $ 50 billion worldwide. In spite of its proven track record, white biotechnology so far did not attract as much capital as red and even green biotechnology. However, the latest finance indicators confirm the continuously growing attractiveness of investment opportunities in white biotechnology. This article discusses white biotechnology's position and potential in the finance market and success factors.  相似文献   
33.
Human non-hairy (glabrous) skin of the fingers, palms and soles wrinkles after prolonged exposure to water. Wrinkling is a sympathetic nervous system-dependent process but little is known about the physiology and potential functions of water-induced skin wrinkling. Here we investigated the idea that wrinkling might improve handling of wet objects by measuring the performance of a large cohort of human subjects (n = 40) in a manual dexterity task. We also tested the idea that skin wrinkling has an impact on tactile acuity or vibrotactile sensation using two independent sensory tasks. We found that skin wrinkling did not improve dexterity in handling wet objects nor did it affect any aspect of touch sensitivity measured. Thus water-induced wrinkling appears to have no significant impact on tactile driven performance or dexterity in handling wet or dry objects.  相似文献   
34.
Cells from glucose-limited chemostat cultures of Cytophaga johnsonae were subjected to a sudden relaxation of substrate limitation by injecting the cells into fresh batch cultures. Starvation experiments were carried out by injecting glucose-limited cells into batch cultures lacking glucose. Transient responses of biomass, glucose uptake and mineralization, ATP content, and viability on different agar media were monitored during these nutrient-shift experiments. Cells reacted differently depending on growth rate and time spent in the chemostat. Fast-growing cells showed an immediate adaptation to the new growth conditions, despite some initial overshoot reactions in ATP and uptake potential. In contrast, slowly growing cells and long-term-adapted cells showed extensive transient growth responses. Glucose uptake and mineralization potentials changed considerably during the transient growth phase before reaching new levels. During the starvation experiments, all cell types displayed a fast decrease in ATP, but the responses of the substrate uptake and mineralization potentials were strongly dependent upon the previous growth rate. Both potentials decreased rapidly in cells with high growth rates. On the other hand, cells with low growth rates maintained 80% of their uptake and mineralization potentials after 8 h of starvation. Thus, slowly growing cells are much better adapted for starvation than are fast-growing cells.  相似文献   
35.
Urinary tract infection (UTI) is the most common bacterial infection leading to substantial morbidity and considerable health care expenditures across all ages. Here we present an exploratory UPLC-MS study of human urine in the context of febrile, complicated urinary tract infection aimed to reveal and identify possible markers of a host response on infection. A UPLC-MS based workflow, taking advantage of Ultra High Resolution (UHR) Qq-ToF-MS, and multivariate data handling were applied to a carefully selected group of 39 subjects with culture-confirmed febrile Escherichia coli UTI. Using a combination of unsupervised and supervised multivariate modeling we have pinpointed a number of peptides specific for UTI. An unequivocal structural identification of these peptides, as O-glycosylated fragments of the human fibrinogen alpha 1 chain, required MS2 and MS3 experiments on two different MS platforms: ESI-UHR-Qq-ToF and ESI-ion trap, a blast search and, finally, confirmation was achieved by matching experimental tandem mass spectra with those of custom synthesized candidate-peptides.In conclusion, exploiting non-targeted UPLC-MS based approach for the investigation of UTI related changes in urine, we have identified and structurally characterized unique O-glycopeptides, which are, to our knowledge, the first demonstration of O-glycosylation of human fibrinogen alpha 1-chain.  相似文献   
36.

Introduction  

Improvement of rheumatoid arthritis (RA) during pregnancy has been causatively associated with increased galactosylation of immunoglobulin G (IgG) N-glycans. Since previous studies were small, did not include the postpartum flare and did not study sialylation, these issues were addressed in the present study.  相似文献   
37.
McDonald KL  Auer M 《BioTechniques》2006,41(2):137, 139, 141 passim
Structural cell biology, which we define as electron microscopic analysis of intact cells, suffered a loss of interest and activity following the advances in light microscopy beginning in the 1990s. Interestingly, it is the wealth of detailed observation in the light microscope that is one of the driving forces for the current renewed interest in electron microscopy (EM). A great many cellular details are simply beyond the resolving power of the light microscope. In this article, we describe how electron microscopists are responding to the demands for better preservation of cells and for ways to view cell ultrastructure in three dimensions at high resolution. We discuss how low temperature methods, especially high-pressure freezing and freeze substitution, reduce the artifacts of conventional EM specimen preparation. We also give a brief introduction to cellular electron tomography, a powerful analytical method that can give near-atomic resolution of cell ultrastructure in three-dimensional (3-D) models.  相似文献   
38.
An improved method for the isolation of rubella virus-like particles (RVLP) from cell culture supernatant of transfected Chinese hamster ovary (CHO24S) cells is described. It employs a combination of membrane filtration with sucrose gradient ultracentrifugation. It was found that staining the RVLP band with Coomassie brilliant blue G (CBB) resulted in the CBB crystals adsorbing RVLP. After ultracentrifugation (25,000 rpm, 3h, 4 degrees C) a sharp blue band with crystals (diameter 30-40 microm) was observed (at a density of 1.250 g/ml at 25 degrees C) in a 30-60% sucrose gradient. Using a combination of SDS-PAGE and Western blotting techniques, E1 rubella virus structural protein was detected only in the solutions derived from the sharp blue band. A decrease in crystal concentration a few millimeters above or below the main band was associated with a decrease in protein concentration. By dilution with a saturated ice-cold 30% sucrose solution it was possible to pellet the crystals by centrifugation (15,000 rpm, 10 min). SDS-PAGE showed a much higher concentration of RVLP structural protein in the pellet than in the supernatant. This RVLP-containing material is especially suitable for the preparation of rubella virus immunoblot stripes.  相似文献   
39.
Cell lines (COLO 320 DM and COLO 320 HSR), established from a human neuroendocrine tumor, contain an amplified cellular oncogene (c-myc). We have previously shown that the homogeneously staining regions (HSRs) of a marker chromosome in the COLO 320 HSR cells that evolved in culture from COLO 320 DM cells contain amplified c-myc. Molecular hybridization in situ has now been used to demonstrate that the HSRs are on both arms of what was once an X chromosome. We also show that amplified c-myc copies are present in the isolated double minute chromosomes (DMs) of the COLO 320 DM cells that were characteristic of the tumor cells initially established from the patient. The results suggest that the amplified c-myc appeared first as DMs and was subsequently transposed to engender HSRs on an X chromosome. The initial COLO 320 tumor cell may have acquired two early replicating (i.e., active) X chromosomes and lost the late replicating (i.e., inactive) X.  相似文献   
40.
Knott JM  Römer P  Sumper M 《FEBS letters》2007,581(16):3081-3086
Polyamines are involved in many fundamental cellular processes. Common polyamines are putrescine, spermidine and spermine. Spermine is synthesized by transfer of an aminopropyl residue derived from decarboxylated S-adenosylmethionine to spermidine. Thermospermine is an isomer of spermine and assumed to be synthesized by an analogous mechanism. However, none of the recently described spermine synthases was investigated for their possible activity as thermospermine synthases. In this work, putative spermine synthases from the diatom Thalassiosira pseudonana and from Arabidopsis thaliana could be identified as thermospermine synthases. These findings may explain the previous result that two putative spermine synthase genes in Arabidopsis produce completely different phenotypes in knock-out experiments. Likely, part of putative spermine synthases identifiable by sequence comparisons represents in fact thermospermine synthases.  相似文献   
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