scholarly journals Inhibition of alternative respiration system of Scheffersomyces stipitis and effect on glucose or xylose fermentation

2021 ◽  
Author(s):  
J A Granados-Arvizu ◽  
M Canizal-Garcia ◽  
L A Madrigal-Perez ◽  
J C González-Hernández ◽  
C Regalado-González
Keyword(s):  
Ethanol Production ◽  
Xylose Fermentation ◽  
Carbon Sources ◽  
Active Role ◽  
Glycolytic Flux ◽  
Alternative Respiration ◽  
Scheffersomyces Stipitis ◽  
Salicylhydroxamic Acid ◽  
Mild Reduction

Abstract Scheffersomyces stipitis is a Crabtree-negative pentose fermenting yeast, which shows a complex respiratory system involving a cytochrome and an alternative salicylhydroxamic acid (SHAM)-sensitive respiration mechanism that is poorly understood. This work aimed to investigate the role of the antimycin A (AA) sensitive respiration and SHAM-sensitive respiration in the metabolism of xylose and glucose by S. stipitis, upon different agitation conditions. Inhibition of the SHAM-sensitive respiration caused a significant (p < 0.05) decrease in glycolytic flux and oxygen consumption when using glucose and xylose under agitation conditions, but without agitation, only a mild reduction was observed. The combination of SHAM and AA abolished respiration, depleting the glycolytic flux using both carbon sources tested, leading to increased ethanol production of 21.05 g/L at 250 rpm for 0.5 M glucose, and 8.3 g/L ethanol using xylose. In contrast, inhibition of only the AA-sensitive respiration, caused increased ethanol production to 30 g/L using 0.5 M glucose at 250 rpm, and 11.3 g/L from 0.5 M xylose without agitation. Results showed that ethanol production can be induced by respiration inhibition, but the active role of SHAM-sensitive respiration should be considered to investigate better conditions to increase and optimize yields.

scholarly journals Role of Hexose Transport in Control of Glycolytic Flux in Saccharomyces cerevisiae

2004 ◽  
Vol 70 (9) ◽  
pp. 5323-5330 ◽  
Author(s):  
Karin Elbing ◽  
Christer Larsson ◽  
Roslyn M. Bill ◽  
Eva Albers ◽  
Jacky L. Snoep ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Glucose Uptake ◽  
Ethanol Production ◽  
Glycolytic Flux ◽  
Glucose Levels ◽  
High Degree ◽  
First Time ◽  
Proportional Decrease ◽  
External Glucose

ABSTRACT The yeast Saccharomyces cerevisiae predominantly ferments glucose to ethanol at high external glucose concentrations, irrespective of the presence of oxygen. In contrast, at low external glucose concentrations and in the presence of oxygen, as in a glucose-limited chemostat, no ethanol is produced. The importance of the external glucose concentration suggests a central role for the affinity and maximal transport rates of yeast's glucose transporters in the control of ethanol production. Here we present a series of strains producing functional chimeras between the hexose transporters Hxt1 and Hxt7, each of which has distinct glucose transport characteristics. The strains display a range of decreasing glycolytic rates resulting in a proportional decrease in ethanol production. Using these strains, we show for the first time that at high glucose levels, the glucose uptake capacity of wild-type S. cerevisiae does not control glycolytic flux during exponential batch growth. In contrast, our chimeric Hxt transporters control the rate of glycolysis to a high degree. Strains whose glucose uptake is mediated by these chimeric transporters will undoubtedly provide a powerful tool with which to examine in detail the mechanism underlying the switch between fermentation and respiration in S. cerevisiae and will provide new tools for the control of industrial fermentations.

Role of spectrin in membrane fusion and in shape change of human erythrocyte ghost

1978 ◽  
Vol 36 (2) ◽  
pp. 328-329
Author(s):  
Hideo Hayashi ◽  
Yoshikazu Hirai ◽  
John T. Penniston
Keyword(s):  
Conformational Changes ◽  
Human Erythrocyte ◽  
Shape Change ◽  
Membrane Surface ◽  
Slight Modification ◽  
Active Role ◽  
Main Role ◽  
Bank Blood ◽  
Human Erythrocyte Ghost

Spectrin is a membrane associated protein most of which properties have been tentatively elucidated. A main role of the protein has been assumed to give a supporting structure to inside of the membrane. As reported previously, however, the isolated spectrin molecule underwent self assemble to form such as fibrous, meshwork, dispersed or aggregated arrangements depending upon the buffer suspended and was suggested to play an active role in the membrane conformational changes. In this study, the role of spectrin and actin was examined in terms of the molecular arrangements on the erythrocyte membrane surface with correlation to the functional states of the ghosts.Human erythrocyte ghosts were prepared from either freshly drawn or stocked bank blood by the method of Dodge et al with a slight modification as described before. Anti-spectrin antibody was raised against rabbit by injection of purified spectrin and partially purified.

Elucidation of block boundaries as the dissolution channels in hydrated cement

1978 ◽  
Vol 36 (1) ◽  
pp. 484-485
Author(s):  
N.V. Belov ◽  
U.I. Papiashwili ◽  
B.E. Yudovich
Keyword(s):  
Liquid Phase ◽  
Grain Boundaries ◽  
Benzoyl Peroxide ◽  
Phase Contrast ◽  
Active Role ◽  
Point Of View ◽  
Hardened Cement ◽  
Hydrated Cement ◽  
Hardened Cement Paste

It has been almost universally adopted that dissolution of solids proceeds with development of uniform, continuous frontiers of reaction.However this point of view is doubtful / 1 /. E.g. we have proved the active role of the block (grain) boundaries in the main phases of cement, these boundaries being the areas of hydrate phases' nucleation / 2 /. It has brought to the supposition that the dissolution frontier of cement particles in water is discrete. It seems also probable that the dissolution proceeds through the channels, which serve both for the liquid phase movement and for the drainage of the incongruant solution products. These channels can be appeared along the block boundaries.In order to demonsrate it, we have offered the method of phase-contrast impregnation of the hardened cement paste with the solution of methyl metacrylahe and benzoyl peroxide. The viscosity of this solution is equal to that of water.

Potential Uses of Vinegar as a Medicine and Related in vivo Mechanisms

2016 ◽  
Vol 86 (3-4) ◽  
pp. 127-151 ◽  
Author(s):  
Zeshan Ali ◽  
Zhenbin Wang ◽  
Rai Muhammad Amir ◽  
Shoaib Younas ◽  
Asif Wali ◽  
...  
Keyword(s):  
Chemical Structure ◽  
Review Paper ◽  
Heart Diseases ◽  
Folk Medicine ◽  
Active Role ◽  
Current Review ◽  
Different Types ◽  
Positive Effect

While the use of vinegar to fi ght against infections and other crucial conditions dates back to Hippocrates, recent research has found that vinegar consumption has a positive effect on biomarkers for diabetes, cancer, and heart diseases. Different types of vinegar have been used in the world during different time periods. Vinegar is produced by a fermentation process. Foods with a high content of carbohydrates are a good source of vinegar. Review of the results of different studies performed on vinegar components reveals that the daily use of these components has a healthy impact on the physiological and chemical structure of the human body. During the era of Hippocrates, people used vinegar as a medicine to treat wounds, which means that vinegar is one of the ancient foods used as folk medicine. The purpose of the current review paper is to provide a detailed summary of the outcome of previous studies emphasizing the role of vinegar in treatment of different diseases both in acute and chronic conditions, its in vivo mechanism and the active role of different bacteria.

Russia’s Market of Mergers and Acquisitions: Stages, Features and Prospects

2009 ◽  
pp. 23-45 ◽  
Author(s):  
A. Radygin
Keyword(s):  
Open Access ◽  
Mergers And Acquisitions ◽  
Corporate Control ◽  
Active Role ◽  
Data Bases ◽  
2008 Financial Crisis ◽  
Legal Norms ◽  
Role Of The State ◽  
Access Data

The article deals with key tendencies in the development of Russia’s market of mergers and acquisitions in the first decade of the 21st century. Quantitative parameters are analyzed by using available in the open access data bases for the years 2003-2008 taking into consideration new tendencies relating to 2008 financial crisis. An active role of the state played in the market of corporate control represents an important factor. Special attention is given to issues of development of Russia’s system of legal norms regulating the market of mergers and acquisitions.

Beyond the Social Determinants of Health

2020 ◽  
Vol 3 ◽  
pp. 1-11
Author(s):  
Laura Hall ◽  
Urpi Pine ◽  
Tanya Shute
Keyword(s):  
Labour Force ◽  
Methodological Approach ◽  
Active Role ◽  
Indigenous Women ◽  
Economic Activities ◽  
The Earth ◽  
The Social ◽  
Weather Changes ◽  
People First

Abstract This paper will reflect on key findings from a Summer 2017 initiative entitled The Role of Culture and Land-Based Healing in Addressing and Ending Violence against Indigenous Women and Two-Spirited People. The Indigenist and decolonizing methodological approach of this work ensured that all research was grounded in experiential and reciprocal ways of learning. Two major findings guide the next phase of this research, complicating the premise that traditional economic activities are healing for Indigenous women and Two-Spirit people. First, the complexities of the mainstream labour force were raised numerous times. Traditional economies are pressured in ongoing ways through exploitative labour practices. Secondly, participants emphasized the importance of attending to the responsibility of nurturing, enriching, and sustaining the wellbeing of soil, water, and original seeds in the process of creating renewal gardens as a healing endeavour. In other words, we have an active role to play in healing the environment and not merely using the environment to heal ourselves. Gardening as research and embodied knowledge was stressed by extreme weather changes including hail in June, 2018, which meant that participants spent as much time talking about the healing of the earth and her systems as the healing of Indigenous women in a context of ongoing colonialism.

Integration of Self-diagnosis in Pascal Law Learning Using STEM Approach

2020 ◽  
Vol 12 (2) ◽  
pp. 104
Author(s):  
Siti Hannah Padliyyah
Keyword(s):  
International Student ◽  
Student Assessment ◽  
Active Role ◽  
Stem Learning ◽  
International Student Assessment ◽  
Science Technology ◽  
Engineering Mathematics ◽  
Post Test ◽  
11Th Grade

Indonesia is ranked 56th out of 65 participating countries in the Program for International Student Assessment (PISA) based on data 2015. According to PISA results, the average science score of Indonesian students is 403, where this number is categorized as low. This is because students are still in the process of understanding and have not yet fully recognized the location of their mistakes. Students can diagnose the location of their mistakes through self-diagnosis activities. Self-diagnosis activities require the active role of students during the learning process. One approach that can increase the active role of students is STEM (Science Technology Engineering Mathematics). However, research at this time is still rarely found self-diagnosis activities that are applied to the STEM approach. Therefore, this research has the aim to find out the increase in mastery of physical concepts and self-diagnosis of students on the STEM learning approach to the theory of poscal law class XI High School.This study uses a One-Group pretest-posttest design with a sample of 30 ini 11th grade highschool from one schools in Bandung. . Based on the findings, there is an increase in mastery of concepts [<g> = 0.51] from pre-test to post-test. In self-diagnosis activities identified that there are differences in scores [z = 1.75; p = 0.9599] student assessment results of researchers and self-scoring results. Deeper self-diagnosis triggers a series of implicit steps that encourage them to rearrange their cognition by correcting the mistakes they make when solving problems. So that learning activities using the STEM approach that involves self-diagnosis activities can improve students' mastery of concepts.

Controlled synthesis of functional Ag, Ag–Au/Au–Ag nanoparticles and their Prussian blue nanocomposites for bioanalytical applications

RSC Advances ◽  
2015 ◽  
Vol 5 (61) ◽  
pp. 49671-49679 ◽  
Author(s):  
Prem. C. Pandey ◽  
Richa Singh ◽  
Yashashwa Pandey
Keyword(s):  
Prussian Blue ◽  
Ag Nanoparticles ◽  
Active Role ◽  
Reducing Agents ◽  
Controlled Synthesis ◽  
Bioanalytical Applications

A facile method for the synthesis of functional AgNPs and bimetallic Ag–Au/Au–Ag are reported, enabling the formation of nanocomposite with prussian blue in a crystalline framework for bioanalytical applications, showing the active role of organic reducing agents and 3-aminopropyltrimethoxysilane.

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