A novel ER membrane protein Ehg1/May24 plays a critical role in maintaining multiple nutrient permeases in yeast under high-pressure perturbation

AbstractPreviously, we isolated 84 deletion mutants in Saccharomyces cerevisiae auxotrophic background that exhibited hypersensitive growth under high hydrostatic pressure and/or low temperature. Here, we observed that 24 deletion mutants were rescued by the introduction of four plasmids (LEU2, HIS3, LYS2, and URA3) together to grow at 25 MPa, thereby suggesting close links between the genes and nutrient uptake. Most of the highly ranked genes were poorly characterized, including MAY24/YPR153W. May24 appeared to be localized in the endoplasmic reticulum (ER) membrane. Therefore, we designated this gene as EHG (ER-associated high-pressure growth gene) 1. Deletion of EHG1 led to reduced nutrient transport rates and decreases in the nutrient permease levels at 25 MPa. These results suggest that Ehg1 is required for the stability and functionality of the permeases under high pressure. Ehg1 physically interacted with nutrient permeases Hip1, Bap2, and Fur4; however, alanine substitutions for Pro17, Phe19, and Pro20, which were highly conserved among Ehg1 homologues in various yeast species, eliminated interactions with the permeases as well as the high-pressure growth ability. By functioning as a novel chaperone that facilitated coping with high-pressure-induced perturbations, Ehg1 could exert a stabilizing effect on nutrient permeases when they are present in the ER.

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Effect of food processing on the antioxidant activity of flavones from Polygonatum odoratum (Mill.) Druce

Open Life Sciences ◽

10.1515/biol-2021-0010 ◽

2021 ◽

Vol 16 (1) ◽

pp. 92-101

Author(s):

Guanghui Xia ◽

Xinhua Li ◽

Zhen Zhang ◽

Yuhang Jiang

Keyword(s):

Antioxidant Activity ◽

High Pressure ◽

Food Processing ◽

Yeast Fermentation ◽

Pressure Treatment ◽

Processing Methods ◽

High Pressure Treatment ◽

Effect Of Food ◽

The Stability

Abstract Polygonatum odoratum (Mill.) Druce (POD) is a natural plant widely used for food and medicine, thanks to its rich content of a strong antioxidant agent called homoisoflavones. However, food processing methods could affect the stability of POD flavones, resulting in changes to their antioxidant activity. This study attempts to evaluate the antioxidant activity of POD flavones subject to different processing methods and determines which method could preserve the antioxidant activity of POD flavones. Therefore, flavones were extracted from POD samples, which had been treated separately with one of the four processing methods: extrusion, baking, high-pressure treatment, and yeast fermentation. After that, the antioxidant activity of the flavones was subject to in vivo tests in zebrafish embryos. The results show that yeast fermentation had the least disruption to the antioxidant activity of POD flavones, making it the most suitable food processing method for POD. By contrast, extrusion and high-pressure treatment both slightly weakened the antioxidant activity of the flavones and should be avoided in food processing. The research results provide a reference for the development and utilization of POD and the protection of its biological activity.

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Quantum-mechanical hydration plays critical role in the stability of firefly oxyluciferin isomers: State-of-the-art calculations of the excited states

The Journal of Chemical Physics ◽

10.1063/5.0031356 ◽

2020 ◽

Vol 153 (20) ◽

pp. 201103

Author(s):

Yoshifumi Noguchi ◽

Miyabi Hiyama ◽

Motoyuki Shiga ◽

Hidefumi Akiyama ◽

Osamu Sugino

Keyword(s):

Excited States ◽

State Of The Art ◽

Critical Role ◽

Quantum Mechanical ◽

The Stability

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A Genome-Wide Screen in Saccharomyces cerevisiae Reveals a Critical Role for Oxidative Phosphorylation in Cellular Tolerance to Lithium Hexafluorophosphate

Cells ◽

10.3390/cells10040888 ◽

2021 ◽

Vol 10 (4) ◽

pp. 888

Author(s):

Xuejiao Jin ◽

Jie Zhang ◽

Tingting An ◽

Huihui Zhao ◽

Wenhao Fu ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Oxidative Phosphorylation ◽

Cellular Response ◽

Critical Role ◽

Lithium Ion ◽

Deletion Mutants ◽

High Concentration ◽

Genome Wide ◽

A Genome ◽

Lithium Hexafluorophosphate

Lithium hexafluorophosphate (LiPF6) is one of the leading electrolytes in lithium-ion batteries, and its usage has increased tremendously in the past few years. Little is known, however, about its potential environmental and biological impacts. In order to improve our understanding of the cytotoxicity of LiPF6 and the specific cellular response mechanisms to it, we performed a genome-wide screen using a yeast (Saccharomyces cerevisiae) deletion mutant collection and identified 75 gene deletion mutants that showed LiPF6 sensitivity. Among these, genes associated with mitochondria showed the most enrichment. We also found that LiPF6 is more toxic to yeast than lithium chloride (LiCl) or sodium hexafluorophosphate (NaPF6). Physiological analysis showed that a high concentration of LiPF6 caused mitochondrial damage, reactive oxygen species (ROS) accumulation, and ATP content changes. Compared with the results of previous genome-wide screening for LiCl-sensitive mutants, we found that oxidative phosphorylation-related mutants were specifically hypersensitive to LiPF6. In these deletion mutants, LiPF6 treatment resulted in higher ROS production and reduced ATP levels, suggesting that oxidative phosphorylation-related genes were important for counteracting LiPF6-induced toxicity. Taken together, our results identified genes specifically involved in LiPF6-modulated toxicity, and demonstrated that oxidative stress and ATP imbalance maybe the driving factors in governing LiPF6-induced toxicity.

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Stabilizing effect of methylcellulose on the dispersion of multi-walled carbon nanotubes in cementitious composites

Nanotechnology Reviews ◽

10.1515/ntrev-2020-0009 ◽

2020 ◽

Vol 9 (1) ◽

pp. 93-104

Author(s):

Mingrui Du ◽

Yuan Gao ◽

Guansheng Han ◽

Luan Li ◽

Hongwen Jing

Keyword(s):

Carbon Nanotubes ◽

Pore Solution ◽

Cementitious Materials ◽

High Ionic Strength ◽

Cementitious Composites ◽

Uniform Distributions ◽

Stabilizing Effect ◽

Multi Walled Carbon Nanotubes ◽

The Stability ◽

Walled Carbon Nanotubes

AbstractMulti-walled carbon nanotubes (MWCNTs) have been added in the plain cementitious materials to manufacture composites with the higher mechanical properties and smart behavior. The uniform distributions of MWCNTs is critical to obtain the desired enhancing effect, which, however, is challenged by the high ionic strength of the cement pore solution. Here, the effects of methylcellulose (MC) on stabilizing the dispersion of MWCNTs in the simulated cement pore solution and the viscosity of MWCNT suspensions werestudied. Further observations on the distributions of MWCNTs in the ternary cementitious composites were conducted. The results showed that MC forms a membranous envelope surrounding MWCNTs, which inhibits the adsorption of cations and maintains the steric repulsion between MWCNTs; thus, the stability of MWCNT dispersion in cement-based composites is improved. MC can also work as a viscosity adjuster that retards the Brownian mobility of MWCNTs, reducing their re-agglomerate within a period. MC with an addition ratio of 0.018 wt.% is suggested to achieve the optimum dispersion stabilizing effect. The findings here provide a way for stabilizing the other dispersed nano-additives in the cementitious composites.

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Roles of vanes in diffuser on stability of centrifugal compressor

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410019844433 ◽

2019 ◽

Vol 233 (14) ◽

pp. 5380-5392

Author(s):

Wangzhi Zou ◽

Xiao He ◽

Wenchao Zhang ◽

Zitian Niu ◽

Xinqian Zheng

Keyword(s):

High Pressure ◽

Centrifugal Compressor ◽

Dynamic Pressure ◽

Pressure Ratio ◽

Pressure Rise ◽

Rotating Stall ◽

Centrifugal Compressors ◽

Compression System ◽

The Stability ◽

Rotating Instability

The stability considerations of centrifugal compressors become increasingly severe with the high pressure ratios, especially in aero-engines. Diffuser is the major subcomponent of centrifugal compressor, and its performance greatly influences the stability of compressor. This paper experimentally investigates the roles of vanes in diffuser on component instability and compression system instability. High pressure ratio centrifugal compressors with and without vanes in diffuser are tested and analyzed. Rig tests are carried out to obtain the compressor performance map. Dynamic pressure measurements and relevant Fourier analysis are performed to identify complex instability phenomena in the time domain and frequency domain, including rotating instability, stall, and surge. For component instability, vanes in diffuser are capable of suppressing the emergence of rotating stall in the diffuser at full speeds, but barely affect the characteristics of rotating instability in the impeller at low and middle speeds. For compression system instability, it is shown that the use of vanes in diffuser can effectively postpone the occurrence of compression system surge at full speeds. According to the experimental results and the one-dimensional flow theory, vanes in diffuser turn the diffuser pressure rise slope more negative and thus improve the stability of compressor stage, which means lower surge mass flow rate.

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Equation of state studies at SILP by laser-driven shock waves

Laser and Particle Beams ◽

10.1017/s0263034600009915 ◽

1996 ◽

Vol 14 (2) ◽

pp. 157-169 ◽

Cited By ~ 8

Author(s):

Yuan Gu ◽

Sizu Fu ◽

Jiang Wu ◽

Songyu Yu ◽

Yuanlong Ni ◽

...

Keyword(s):

Shock Wave ◽

High Pressure ◽

Equation Of State ◽

Shock Waves ◽

Target Surface ◽

Shock Adiabats ◽

Pressure Shock ◽

Aluminum Target ◽

Laser Illumination ◽

The Stability

The experimental progress of laser equation of state (EOS) studies at Shanghai Institute of Laser Plasma (SILP) is discussed in this paper. With a unique focal system, the uniformity of the laser illumination on the target surface is improved and a laser-driven shock wave with good spatial planarity is obtained. With an inclined aluminum target plane, the stability of shock waves are studied, and the corresponding thickness range of the target of laser-driven shock waves propagating steadily are given. The shock adiabats of Cu, Fe, SiO2 are experimentally measured. The pressure in the material is heightened remarkably with the flyer increasing pressure, and the effect of the increasing pressure is observed. Also, the high-pressure shock wave is produced and recorded in the experimentation of indirect laser-driven shock waves with the hohlraum target.

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DNA Genome Size Affects the Stability of the Adenovirus Virion

Journal of Virology ◽

10.1128/jvi.01644-08 ◽

2008 ◽

Vol 83 (4) ◽

pp. 2025-2028 ◽

Cited By ~ 23

Author(s):

Adam C. Smith ◽

Kathy L. Poulin ◽

Robin J. Parks

Keyword(s):

Genome Size ◽

Critical Role ◽

Heat Stability ◽

Helper Virus ◽

Heat Inactivation ◽

Similar Relationship ◽

Viral Dna ◽

A Genome ◽

The Stability ◽

Replication Defective Adenovirus

ABSTRACT Replication-defective adenovirus (Ad) vectors can vary considerably in genome length, but whether this affects virion stability has not been investigated. Helper-dependent Ad vectors with a genome size of ∼30 kb were 100-fold more sensitive to heat inactivation than their parental helper virus (>36 kb), and increasing the genome size of the vector significantly improved heat stability. A similar relationship between genome size and stability existed for Ad with early region 1 deleted. Loss of infectivity was due to release of vertex proteins, followed by disintegration of the capsid. Thus, not only does the viral DNA encode all of the heritable information essential for virus replication, it also plays a critical role in maintaining capsid strength and integrity.

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Analysis of Urban Effects in Oklahoma City using a Dense Surface Observing Network

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-15-0206.1 ◽

2016 ◽

Vol 55 (3) ◽

pp. 723-741 ◽

Cited By ~ 22

Author(s):

Xiao-Ming Hu ◽

Ming Xue ◽

Petra M. Klein ◽

Bradley G. Illston ◽

Sheng Chen

Keyword(s):

Metropolitan Area ◽

Land Surface ◽

Critical Role ◽

Central Business District ◽

Temperature Inversion ◽

Oklahoma City ◽

Near Surface ◽

Open Questions ◽

The Stability ◽

Business District

AbstractMany studies have investigated urban heat island (UHI) intensity for cities around the world, which is normally quantified as the temperature difference between urban location(s) and rural location(s). A few open questions still remain regarding the UHI, such as the spatial distribution of UHI intensity, temporal (including diurnal and seasonal) variation of UHI intensity, and the UHI formation mechanism. A dense network of atmospheric monitoring sites, known as the Oklahoma City (OKC) Micronet (OKCNET), was deployed in 2008 across the OKC metropolitan area. This study analyzes data from OKCNET in 2009 and 2010 to investigate OKC UHI at a subcity spatial scale for the first time. The UHI intensity exhibited large spatial variations over OKC. During both daytime and nighttime, the strongest UHI intensity is mostly confined around the central business district where land surface roughness is the highest in the OKC metropolitan area. These results do not support the roughness warming theory to explain the air temperature UHI in OKC. The UHI intensity of OKC increased prominently around the early evening transition (EET) and stayed at a fairly constant level throughout the night. The physical processes during the EET play a critical role in determining the nocturnal UHI intensity. The near-surface rural temperature inversion strength was a good indicator for nocturnal UHI intensity. As a consequence of the relatively weak near-surface rural inversion, the strongest nocturnal UHI in OKC was less likely to occur in summer. Other meteorological factors (e.g., wind speed and cloud) can affect the stability/depth of the nighttime boundary layer and can thus modulate nocturnal UHI intensity.

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Synthetic lethality screen identifies a novel yeast myosin I gene (MYO5): myosin I proteins are required for polarization of the actin cytoskeleton.

The Journal of Cell Biology ◽

10.1083/jcb.133.6.1277 ◽

1996 ◽

Vol 133 (6) ◽

pp. 1277-1291 ◽

Cited By ~ 156

Author(s):

H V Goodson ◽

B L Anderson ◽

H M Warrick ◽

L A Pon ◽

J A Spudich

Keyword(s):

Actin Cytoskeleton ◽

Synthetic Lethality ◽

Critical Role ◽

Neck Region ◽

Actin Binding ◽

Cell Physiology ◽

Deletion Mutants ◽

Tail Domain ◽

Amino Terminal ◽

Myosin I

The organization of the actin cytoskeleton plays a critical role in cell physiology in motile and nonmotile organisms. Nonetheless, the function of the actin based motor molecules, members of the myosin superfamily, is not well understood. Deletion of MYO3, a yeast gene encoding a "classic" myosin I, has no detectable phenotype. We used a synthetic lethality screen to uncover genes whose functions might overlap with those of MYO3 and identified a second yeast myosin 1 gene, MYO5. MYO5 shows 86 and 62% identity to MYO3 across the motor and non-motor regions. Both genes contain an amino terminal motor domain, a neck region containing two IQ motifs, and a tail domain consisting of a positively charged region, a proline-rich region containing sequences implicated in ATP-insensitive actin binding, and an SH3 domain. Although myo5 deletion mutants have no detectable phenotype, yeast strains deleted for both MYO3 and MYO5 have severe defects in growth and actin cytoskeletal organization. Double deletion mutants also display phenotypes associated with actin disorganization including accumulation of intracellular membranes and vesicles, cell rounding, random bud site selection, sensitivity to high osmotic strength, and low pH as well as defects in chitin and cell wall deposition, invertase secretion, and fluid phase endocytosis. Indirect immunofluorescence studies using epitope-tagged Myo5p indicate that Myo5p is localized at actin patches. These results indicate that MYO3 and MYO5 encode classical myosin I proteins with overlapping functions and suggest a role for Myo3p and Myo5p in organization of the actin cytoskeleton of Saccharomyces cerevisiae.

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