Search results for "SAC"

How Long-Term Contracts can Mitigate Inefficient Renegotiation Arising Due to Loss Aversion

2021

A loss-averse buyer and seller face an uncertain environment. Should they write a long-term contract or wait until the state of the world is realized? I show that simple long-term contracts perform better than insinuated in Herweg and Schmidt (2015), even though loss aversion makes renegotiation sometimes inefficient. During renegotiation, the outcome induced by the long-term contract constitutes the reference point to which the parties compare gains and losses induced by the renegotiated transaction. Whereas Herweg and Schmidt consider that the long-term contract is always performed, it should not in "bad" states. This alters the threat point in renegotiation, making it easier to renegotia…

First report of postharvest fruit rot caused by fusarium sacchari on lady finger banana in Italy

2020

Role of Solvent on Protein-Matrix Coupling in MbCO Embedded in Water-Saccharide Systems: A Fourier Transform Infrared Spectroscopy Study

2006

AbstractEmbedding protein in sugar systems of low water content enables one to investigate the protein dynamic-structure function in matrixes whose rigidity is modulated by varying the content of residual water. Accordingly, studying the dynamics and structure thermal evolution of a protein in sugar systems of different hydration constitutes a tool for disentangling solvent rigidity from temperature effects. Furthermore, studies performed using different sugars may give information on how the detailed composition of the surrounding solvent affects the internal protein dynamics and structural evolution. In this work, we compare Fourier transform infrared spectroscopy measurements (300–20K) o…

The Saccharomyces cerevisiae zinc finger proteins Msn2p and Msn4p are required for transcriptional induction through the stress response element (STR…

1996

The MSN2 and MSN4 genes encode homologous and functionally redundant Cys2His2 zinc finger proteins. A disruption of both MSN2 and MSN4 genes results in a higher sensitivity to different stresses, including carbon source starvation, heat shock and severe osmotic and oxidative stresses. We show that MSN2 and MSN4 are required for activation of several yeast genes such as CTT1, DDR2 and HSP12, whose induction is mediated through stress-response elements (STREs). Msn2p and Msn4p are important factors for the stress-induced activation of STRE dependent promoters and bind specifically to STRE-containing oligonucleotides. Our results suggest that MSN2 and MSN4 encode a DNA-binding component of the…

Lack of correlation between trehalose accumulation, cell viability and intracellular acidification as induced by various stresses in Saccharomyces ce…

1998

A pma1-1 mutant of Saccharomyces cerevisiae with reduced H+-ATPase activity and the isogenic wild-type strain accumulated high levels of trehalose in response to a temperature upshift to 40 éC and after addition of 10% ethanol, but only modest levels in response to a rapid drop in external pH and after addition of decanoic acid. There was, however, no correlation between the absolute levels of trehalose in the stressed cells and their viability. All these treatments induced a significant decrease in intracellular pH, and surprisingly, this decrease was very similar in both strains, indicating that intracellular acidification could not be the triggering mechanism for trehalose accumulation i…

Engineering of sugar transporters for improvement of xylose utilization during high-temperature alcoholic fermentation in Ogataea polymorpha yeast

2020

Abstract Background Xylose transport is one of the bottlenecks in the conversion of lignocellulosic biomass to ethanol. Xylose consumption by the wild-type strains of xylose-utilizing yeasts occurs once glucose is depleted resulting in a long fermentation process and overall slow and incomplete conversion of sugars liberated from lignocellulosic hydrolysates. Therefore, the engineering of endogenous transporters for the facilitation of glucose-xylose co-consumption is an important prerequisite for efficient ethanol production from lignocellulosic hydrolysates. Results In this study, several engineering approaches formerly used for the low-affinity glucose transporters in Saccharomyces cerev…

Focal Transcriptional Activity of Murine Cytomegalovirus during Latency in the Lungs

1999

ABSTRACT Interstitial pneumonia is a frequent and critical manifestation of human cytomegalovirus (CMV) disease in immunocompromised patients, in particular in recipients of bone marrow transplantation. Previous work in the murine CMV infection model has identified the lungs as a major organ site of CMV latency and recurrence. It was open to question whether the viral genome is transcriptionally silent or active during latency. Transcription could be latency associated and thus be part of the latency phenotype. Alternatively, transcriptional activity could reflect episodes of reactivation. We demonstrate here that transcription of the immediate-early (IE) transcription unit ie1-ie3 selectiv…

Study of supramolecular structures released from the cell wall of Candida albicans by ethylenediamine treatment

1996

Candida albicans cell wall components were analyzed by ethylenediamine (EDA) treatment. Based on their different solubility properties, the cell wall components produced three fractions (A, B, and C). Fractions B (EDA-soluble, water-insoluble) and C (EDA-insoluble) contained glucan, chitin, and protein in different proportions. After zymolyase (mainly a beta-glucanase complex) or chitinase treatment of fractions B and C, more polysaccharides and proteins were solubilized by a second EDA treatment, suggesting that the solubility of the polymers in EDA depends on the degree of polymer interactions. Western blot analysis using two monoclonal antibodies (1B12 and 4C12) revealed electrophoretic …

Immobilisation of yeast cells on the surface of hydroxyapatite ceramics

2011

Hydroxyapatite (HAP) ceramics was tested for the first time for the possibility of being used as a new carrier for the immobilisation of yeast cells that are both model organisms for eukaryotic cell investigations and producers, which is important in classical and modern biotechnological processes. It was shown that under typical immobilisation conditions yeast (Saccharomyces cerevisiae) has no affinity to HAP ceramics. A novel method for yeast immobilisation was developed. This new method includes the joint incubation of a carrier with the cells, the sedimentation and adhesion of cells on the carrier and the dehydration of obtained preparations. It was shown that the sedimentation and adhe…

Proteinaceous and oligosaccharidic elicitors induce different calcium signatures in the nucleus of tobacco cells.

2005

We previously reported elevated cytosolic calcium levels in tobacco cells in response to elicitors [D. Lecourieux, C. Mazars, N. Pauly, R. Ranjeva, A. Pugin, Analysis and effects of cytosolic free calcium elevations in response to elicitors in Nicotiana plumbaginifolia cells, Plant Cell 14 (2002) 2627-2641]. These data suggested that in response to elicitors, Ca2+, as a second messenger, was involved in both systemic acquired resistance (RSA) and/or hypersensitive response (HR) depending on calcium signature. Here, we used transformed tobacco cells with apoaequorin expressed in the nucleus to monitor changes in free nuclear calcium concentrations ([Ca2+](nuc)) in response to elicitors. Two …