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521.
Dragomir Milovanovic Mitja Platen Meike Junius Ulf Diederichsen Iwan A. T. Schaap Alf Honigmann Reinhard Jahn Geert van den Bogaart 《The Journal of biological chemistry》2016,291(15):7868-7876
Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is a minor component of total plasma membrane lipids, but it has a substantial role in the regulation of many cellular functions, including exo- and endocytosis. Recently, it was shown that PI(4,5)P2 and syntaxin 1, a SNARE protein that catalyzes regulated exocytosis, form domains in the plasma membrane that constitute recognition sites for vesicle docking. Also, calcium was shown to promote syntaxin 1 clustering in the plasma membrane, but the molecular mechanism was unknown. Here, using a combination of superresolution stimulated emission depletion microscopy, FRET, and atomic force microscopy, we show that Ca2+ acts as a charge bridge that specifically and reversibly connects multiple syntaxin 1/PI(4,5)P2 complexes into larger mesoscale domains. This transient reorganization of the plasma membrane by physiological Ca2+ concentrations is likely to be important for Ca2+-regulated secretion. 相似文献
522.
Mark K Titulaer Ivar Siccama Lennard J Dekker Angelique LCT van Rijswijk Ron MA Heeren Peter A Sillevis Smitt Theo M Luider 《BMC bioinformatics》2006,7(1):403-16
Background
Statistical comparison of peptide profiles in biomarker discovery requires fast, user-friendly software for high throughput data analysis. Important features are flexibility in changing input variables and statistical analysis of peptides that are differentially expressed between patient and control groups. In addition, integration the mass spectrometry data with the results of other experiments, such as microarray analysis, and information from other databases requires a central storage of the profile matrix, where protein id's can be added to peptide masses of interest. 相似文献523.
Jorge Cubo Meike Köhler Vivian de Buffrénil 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2017,50(4):495-503
Iberosuchus macrodon is a Cenozoic crocodyliform interpreted as a terrestrial, cursorial form. To assess whether this adaptation was accompanied by a high growth rate and an elevated resting metabolic rate (two features commonly attributed to several terrestrial Triassic Crocodylomorpha based on histology), we studied bone histology in the femora of two specimens attributed to I. macrodon. Beyond this question is the broader problem of the possible survival to the Cretaceous‐Palaeogene extinction event of tachymetabolic sauropsids other than birds. At mid‐diaphysis, bone cortices in Iberosuchus are made of a parallel‐fibred tissue that turns locally to true lamellar bone. Cortical vascularization consists of simple longitudinal canals forming a network of medium density. The spacing pattern of conspicuous lines of arrested growth suggests asymptotic growth for Iberosuchus. This general histological structure prevails also in the metaphyseal region of the bones. It is basically similar to that encountered in certain large lizards adapted to active predation, the Varanidae and the Teidae. In one of the two Iberosuchus femora, however, an intracortical meniscus made of a tissue displaying a global radial architecture occurs in the region of the fourth trochanter. Histologically, the latter can be interpreted either as compacted spongiosa or as a fibro‐lamellar complex with a gross radial orientation, a tissue corresponding to fast periosteal apposition. These observations suggest that Iberosuchus basically had a slow, cyclical growth indicative of an ecto‐poikilothermic, lizard‐like, resting metabolic rate. However, it might also have retained a limited capacity for fast periosteal accretion in relation to local morphogenetic requirements as, for instance, the development of crests or trochanters. 相似文献
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Karen Wohlers Astrid Wirtz Alexander Reiter Marco Oldiges Meike Baumgart Michael Bott 《Microbial biotechnology》2021,14(6):2592-2604
5-Ketofructose (5-KF) is a promising low-calorie natural sweetener with the potential to reduce health problems caused by excessive sugar consumption. It is formed by periplasmic oxidation of fructose by fructose dehydrogenase (Fdh) of Gluconobacter japonicus, a membrane-bound three-subunit enzyme containing FAD and three haemes c as prosthetic groups. This study aimed at establishing Pseudomonas putida KT2440 as a new cell factory for 5-KF production, as this host offers a number of advantages compared with the established host Gluconobacter oxydans. Genomic expression of the fdhSCL genes from G. japonicus enabled synthesis of functional Fdh in P. putida and successful oxidation of fructose to 5-KF. In a batch fermentation, 129 g l−1 5-KF were formed from 150 g l−1 fructose within 23 h, corresponding to a space-time yield of 5.6 g l−1 h−1. Besides fructose, also sucrose could be used as substrate for 5-KF production by plasmid-based expression of the invertase gene inv1417 from G. japonicus. In a bioreactor cultivation with pulsed sucrose feeding, 144 g 5-KF were produced from 358 g sucrose within 48 h. These results demonstrate that P. putida is an attractive host for 5-KF production. 相似文献
527.
Construction material plays an increasingly important role in the environmental impacts of buildings. In order to investigate impacts of materials on a building level, we present a bottom‐up building stock model that uses three‐dimensional and geo‐referenced building data to determine volumetric information of material stocks in Swiss residential buildings. We used a probabilistic modeling approach to calculate future material flows for the individual buildings. We investigated six scenarios with different assumptions concerning per‐capita floor area, building stock turnover, and construction material. The Swiss building stock will undergo important structural changes by 2035. While this will lead to a reduced number in new constructions, material flows will increase. Total material inflow decreases by almost half while outflows double. In 2055, the total amount of material in‐ and outflows are almost equal, which represents an important opportunity to close construction material cycles. Total environmental impacts due to production and disposal of construction material remain relatively stable over time. The cumulated impact is slightly reduced for the wood‐based scenario. The scenario with more insulation material leads to slightly higher material‐related emissions. An increase in per‐capita floor area or material turnover will lead to a considerable increase in impacts. The new modeling approach overcomes the limitations of previous bottom‐up building models and allows for investigating building material flows and stocks in space and time. This supports the development of tailored strategies to reduce the material footprint and environmental impacts of buildings and settlements. 相似文献
528.
Jennifer L. St. Sauver Susan A. Weston Elizabeth J. Atkinson Michaela E. Mc Gree Michelle M. Mielke Thomas A. White Amanda A. Heeren Janet E. Olson Walter A. Rocca Allyson K. Palmer Steven R. Cummings Roger A. Fielding Suzette J. Bielinski Nathan K. LeBrasseur 《Aging cell》2023,22(12):e14006
A robust and heterogenous secretory phenotype is a core feature of most senescent cells. In addition to mediators of age-related pathology, components of the senescence associated secretory phenotype (SASP) have been studied as biomarkers of senescent cell burden and, in turn, biological age. Therefore, we hypothesized that circulating concentrations of candidate senescence biomarkers, including chemokines, cytokines, matrix remodeling proteins, and growth factors, could predict mortality in older adults. We assessed associations between plasma levels of 28 SASP proteins and risk of mortality over a median follow-up of 6.3 years in 1923 patients 65 years of age or older with zero or one chronic condition at baseline. Overall, the five senescence biomarkers most strongly associated with an increased risk of death were GDF15, RAGE, VEGFA, PARC, and MMP2, after adjusting for age, sex, race, and the presence of one chronic condition. The combination of biomarkers and clinical and demographic covariates exhibited a significantly higher c-statistic for risk of death (0.79, 95% confidence interval (CI): 0.76–0.82) than the covariates alone (0.70, CI: 0.67–0.74) (p < 0.001). Collectively, these findings lend further support to biomarkers of cellular senescence as informative predictors of clinically important health outcomes in older adults, including death. 相似文献
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Rubén García-Martínez Nekane Marín-Moratalla Xavier Jordana Meike Köhler 《Comptes Rendus Palevol》2011,10(5-6):489-498
Though bone histology has become a powerful tool to reconstruct life history strategies and physiology in living and extinct reptiles and amphibians, it is of limited use in mammals. Dormice (Myoxidae) are good candidates for assessing the relation between bone microstructure and life history due to their long life span, marked physiological cycles and negligible bone remodelling. We carried out the most comprehensive study so far analyzing 16 wild individuals of unknown age belonging to two different species of dormice, Glis glis and Eliomys quercinus. Our study shows a high degree of consistency in the number of resting lines present in bones of the same individual, with femora providing the most accurate age estimations. Moreover, the presence of a single LAG in some juveniles allows discerning between offspring from different reproductive events (early or late litters). 相似文献