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481.
Elevated values of molar growth yield (Yx/s = 14–26 g mol–1) were obtained during exponential growth (μ > 0.4 h–1) of Zymomonas mobilis ATCC 29191 by using reduced concentrations of glucose (6.25–100 mM) and increased oxygen supply (E
h > 300 mV) in the growth medium, as compared to the Yx/s of anaerobic exponential growth (8–10 g mol–1). Aerobically grown cells showed an increased maximum growth rate (μmax), and a reduced specific glucose consumption rate (qs), and specific ethanol formation rate (qp), thus demonstrating a more pronounced energy-coupling growth under oxic conditions. These results can be neither explained
by the concept of a solely operating Entner-Doudoroff pathway as an ATP source in aerobically growing cultures of Z. mobilis nor considered to be consistent with existing data on the lack of the Pasteur effect in this bacterium. Therefore, the results
rather give evidence for the essential contribution of aerobic ATP generation under the reported conditions.
Received: 24 September 1996 / Accepted: 9 December 1996 相似文献
482.
Anca Farkas Florina Mereuti Dorina Podar Carmen Roba Ramona Bălc 《Geomicrobiology journal》2020,37(9):867-876
Abstract The aim of this study was to investigate the extent of heavy metal (HM) pollution and its effect on microorganisms from rhizosphere soil in Baia Mare area (Maramure? County, Romania). Two sites with different contamination degrees were included in the study: one with a long history of mining activities and one within a drinking water safeguard zone. Rhizosphere soil samples were characterized with respect to physico-chemical parameters and the Cd, Cu, Pb and Zn contents. Native bacteria were investigated for HM tolerance and biofilm formation under toxic exposure by the microdilution assay. The most resistant strains were identified and the minimum inhibitory concentrations for HMs were determined. Cd, Cu, Pb and Zn exceeded the intervention threshold in Bozânta tailings site, while Pb content exceeded the intervention level within the area of the drinking water treatment plant. Cd showed a very high potential ecological risk in Bozânta area. The long-term exposure to HMs contributed to the selection of HM-tolerant and weakly adherent strains. Biofouling was significantly reduced under the influence of copper ions. Arthrobacter, Rhodococcus and Acidovorax strains with exceptional resistant profiles were isolated from the tailings site, indicating the important role of native microorganisms in rhizosphere ecosystems of contaminated sites. 相似文献
483.
Soroush Sharbati-Tehrani Barbara Kutz-Lohroff Ramona Bergbauer Jutta Scholven Ralf Einspanier 《BMC molecular biology》2008,9(1):34
Background
MicroRNAs (miRNAs) are small endogenous non-coding interfering RNA molecules regarded as major regulators in eukaryotic gene expression. Different methods are employed for miRNA expression profiling. For a better understanding of their role in essential biological processes, convenient methods for differential miRNA expression analysis are required. 相似文献484.
Silvia Pelucchi Chiara Macchi Laura D'Andrea Paolo Dionigi Rossi Michela Carola Speciani Ramona Stringhi Massimiliano Ruscica Beatrice Arosio Monica Di Luca Matteo Cesari Valeria Edefonti Elena Marcello 《Aging cell》2023,22(9):e13918
Frailty is a geriatric syndrome that results from multisystem impairment caused by age-associated accumulation of deficits. The frailty index is used to define the level of frailty. Several studies have searched for molecular biomarkers associated with frailty, to meet the needs for personalized care. Cyclase-associated protein 2 (CAP2) is a multifunctional actin-binding protein involved in various physiological and pathological processes, that might reflect frailty's intrinsic complexity. This study aimed to investigate the association between frailty index and circulating CAP2 concentration in 467 community-dwelling older adults (median age: 79; range: 65–92 years) from Milan, Italy. The selected robust regression model showed that circulating CAP2 concentration was not associated with chronological age, as well as sex and education. However, circulating CAP2 concentration was significantly and inversely associated with the frailty index: a 0.1-unit increase in frailty index leads to ~0.5-point mean decrease in CAP2 concentration. Furthermore, mean CAP2 concentration was significantly lower in frail participants (i.e., frailty index ≥0.25) than in non-frail participants. This study shows the association between serum CAP2 concentration and frailty status for the first time, highlighting the potential of CAP2 as a biomarker for age-associated accumulation of deficits. 相似文献
485.
Laura Pasquardini Simone Berneschi Andrea Barucci Franco Cosi Ramona Dallapiccola Massimiliano Insinna Lorenzo Lunelli Gualtiero Nunzi Conti Cecilia Pederzolli Simone Salvadori Silvia Soria 《Journal of biophotonics》2013,6(2):178-187
Whispering gallery mode resonators (WGMR), as silica microspheres, have been recently proposed as an efficient tool for the realisation of optical biosensors. In this work we present a functionalization procedure based on the DNA‐aptamer sequence immobilization on WGMR, able to recognize specifically thrombin or VEGF protein, preserving a high Q factor. The protein binding was optically characterized in terms of specificity in buffer solution or in 10% diluted human serum. Simulation of the protein flow was found in good agreement with experimental data. The aptasensor was also chemically regenerated and tested again, demonstrating the reusability of our system. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
486.
487.
Historical time series for average human height exhibit short- and medium-term cycles that can be associated with business cycles in the 19th and 20th century. Using spectral analysis, we calculate the proportion of cyclical fluctuations in height series attributable to economic cycles. We also analyze the extent to which these cyclical phenomena change over time. In the U.S., the association between height cycles and business cycles was weaker among richer segments of the society, and weaker among men than among women. Additionally, the relationship diminished over time, probably with the rich preceding the population at large. 相似文献
488.