scholarly journals Investigation of the impact of a broad range of temperatures on the physiological and transcriptional profiles of Zymomonas mobilis ZM4 for high-temperature-tolerant recombinant strain development

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Runxia Li ◽  
Wei Shen ◽  
Yongfu Yang ◽  
Jun Du ◽  
Mian Li ◽  
...  
Keyword(s):  
High Temperature ◽  
Ethanol Production ◽  
Heat Tolerance ◽  
Zymomonas Mobilis ◽  
Glucose Utilization ◽  
Effect Of Temperature ◽  
Rna Seq ◽  
Transcriptional Profiles ◽  
Different Temperatures ◽  
The Impact

AbstractThe model ethanologenic bacterium Zymomonas mobilis has many advantages for diverse biochemical production. Although the impact of temperature especially high temperature on the growth and ethanol production of Z. mobilis has been reported, the transcriptional profiles of Z. mobilis grown at different temperatures have not been systematically investigated. In this study, Z. mobilis wild-type strain ZM4 was used to study the effect of a broad range of temperatures of 24, 30, 36, 40, and 45 °C on cell growth and morphology, glucose utilization and ethanol production, as well as the corresponding global gene expression profiles using RNA-Seq-based transcriptomics. In addition, a recombinant Z. mobilis strain expressing reporter gene EGFP (ZM4_EGFP) was constructed to study the effect of temperature on heterologous protein expression at different temperatures. Our result demonstrated that the effect of temperature on the growth and morphology of ZM4 and ZM4_EGFP were similar. The biomass of these two strains decreased along with the temperature increase, and an optimal temperature range is needed for efficient glucose utilization and ethanol production. Temperatures lower or higher than normal temperature investigated in this work was not favorable for the glucose utilization and ethanol production as well as the expression of exogenous protein EGFP based on the results of flow cytometry and Western blot. Temperature also affected the transcriptional profiles of Z. mobilis especially under high temperature. Compared with ZM4 cultured at 30 °C, 478 genes were up-regulated and 481 genes were down-regulated at 45 °C. The number of differentially expressed genes of ZM4 cultured at other temperatures (24, 36 or 40 °C) was relatively small though compared with those at 30 °C. Since temperature usually increases during the fermentation process, and heat tolerance is one of the important robustness traits of industrial strains, candidate genes related to heat resistance based on our RNA-Seq result and literature report were then selected for genetics study using the strategies of plasmid overexpression of candidate gene or replacement of the native promoter of candidate gene by an inducible Ptet promoter. The genetics studies indicated that ZMO0236, ZMO1335, ZMO0994, operon groESL, and cspL, which encodes Mrp family chromosome partitioning ATPase, flavoprotein WrbA, an uncharacterized protein, chaperonin Cpn10 and GroEL, and an exogenous cold shock protein, respectively, were associated with heat tolerance, and recombinant strains over-expressing these genes can improve their heat tolerance. Our work thus not only explored the effects of temperature on the expression of exogenous gene EGFP and endogenous genes, but also selected and confirmed several genes associated with heat tolerance in Z. mobilis, which provided a guidance on identifying candidate genes associated with phenotypic improvement through systems biology strategy and genetics studies for other microorganisms.

scholarly journals Effect of temperature, CO2 and O2 on motility and mobility of Anisakidae larvae

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aiyan Guan ◽  
Inge Van Damme ◽  
Frank Devlieghere ◽  
Sarah Gabriël
Keyword(s):  
Enzymatic Digestion ◽  
Infected Fish ◽  
Effect Of Temperature ◽  
Video Recordings ◽  
Different Temperatures ◽  
Semi Solid ◽  
Zoonotic Parasites ◽  
The Impact ◽  
Phosphate Buffered Saline

AbstractAnisakidae, marine nematodes, are underrecognized fish-borne zoonotic parasites. Studies on factors that could trigger parasites to actively migrate out of the fish are very limited. The objective of this study was to assess the impact of different environmental conditions (temperature, CO2 and O2) on larval motility (in situ movement) and mobility (migration) in vitro. Larvae were collected by candling or enzymatic digestion from infected fish, identified morphologically and confirmed molecularly. Individual larvae were transferred to a semi-solid Phosphate Buffered Saline agar, and subjected to different temperatures (6 ℃, 12 ℃, 22 ℃, 37 ℃) at air conditions. Moreover, different combinations of CO2 and O2 with N2 as filler were tested, at both 6 °C and 12 °C. Video recordings of larvae were translated into scores for larval motility and mobility. Results showed that temperature had significant influence on larval movements, with the highest motility and mobility observed at 22 ℃ for Anisakis spp. larvae and 37 ℃ for Pseudoterranova spp. larvae. During the first 10 min, the median migration of Anisakis spp. larvae was 10 cm at 22 ℃, and the median migration of Pseudoterranova spp. larvae was 3 cm at 37 ℃. Larval mobility was not significantly different under the different CO2 or O2 conditions at 6 °C and 12 ℃. It was concluded that temperature significantly facilitated larval movement with the optimum temperature being different for Anisakis spp. and Pseudoterranova spp., while CO2 and O2 did not on the short term. This should be further validated in parasite-infected/spiked fish fillets.

scholarly journals The modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo, China

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Rui Zhang ◽  
Yujie Meng ◽  
Hejia Song ◽  
Ran Niu ◽  
Yu Wang ◽  
...  
Keyword(s):  
Air Pollution ◽  
High Temperature ◽  
Air Pollutants ◽  
Meteorological Data ◽  
Effect Of Temperature ◽  
Distributed Lag ◽  
Modification Effect ◽  
Incidence Risk ◽  
The Impact ◽  
The Relationship

Abstract Background Although exposure to air pollution has been linked to many health issues, few studies have quantified the modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo, China. Methods The data of daily incidence of influenza and the relevant meteorological data and air pollution data in Ningbo from 2014 to 2017 were retrieved. Low, medium and high temperature layers were stratified by the daily mean temperature with 25th and 75th percentiles. The potential modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo was investigated through analyzing the effects of air pollutants stratified by temperature stratum using distributed lag non-linear model (DLNM). Stratified analysis by sex and age were also conducted. Results Overall, a 10 μg/m3 increment of O3, PM2.5, PM10 and NO2 could increase the incidence risk of influenza with the cumulative relative risk of 1.028 (95% CI 1.007, 1.050), 1.061 (95% CI 1.004, 1.122), 1.043 (95% CI 1.003, 1.085), and 1.118 (95% CI 1.028, 1.216), respectively. Male and aged 7–17 years were more sensitive to air pollutants. Through the temperature stratification analysis, we found that temperature could modify the impacts of air pollution on daily incidence of influenza with high temperature exacerbating the impact of air pollutants. At high temperature layer, male and the groups aged 0–6 years and 18–64 years were more sensitive to air pollution. Conclusion Temperature modified the relationship between air pollution and daily incidence of influenza and high temperature would exacerbate the effects of air pollutants in Ningbo.

The effect of temperature on the kinetics of ethanol production by strains of Zymomonas mobilis

1981 ◽  
Vol 3 (6) ◽  
pp. 291-296 ◽  
Author(s):  
K. J. Lee ◽  
M. L. Skotnicki ◽  
D. E. Tribe ◽  
P. L. Rogers
Keyword(s):  
Ethanol Production ◽  
Zymomonas Mobilis ◽  
Effect Of Temperature ◽  
Kinetics Of

Mechanical Response of T300/BMP350 Composites under Tensile Loading at Room and Elevated Temperatures

2014 ◽  
Vol 1035 ◽  
pp. 138-143
Author(s):  
Ping Zhou ◽  
Pu Rong Jia ◽  
Wen Ge Pan
Keyword(s):  
High Temperature ◽  
Failure Modes ◽  
Elevated Temperatures ◽  
Mechanical Response ◽  
Effect Of Temperature ◽  
Matrix Composites ◽  
Stress Strain ◽  
Damage And Failure ◽  
Different Temperatures ◽  
Static Tensile

In this paper, the effect of elevated temperature on the behavior of carbon fiber-reinforced T300/BMP350 unidirectional laminates was studied by loading static tensile on 0°, 90°and ±45° lay-up. The stress-strain relationships of the laminates under different temperatures were obtained. The effect of temperature on the mechanical properties of materials was systematically studied. The damage and failure mechanisms of the material were studied by analyzing the material stress-strain curves and the failure modes. Results show that the T300/BMP350 polyimide matrix composites have a strong resistance to high temperature. For 0° and 90° lay-up, the retentions of tensile strength and modulus are more than 80% and 50%, respectively. High temperature has little effect on the material failure modes. Finally, based on the test results, an empirical formula which relates strength and temperature of the material was fitted.

scholarly journals Effect of Change in Ambient Temperature on Creep of Concrete

2021 ◽  
Vol 2 (1) ◽  
pp. 17-22
Author(s):  
Zainab Kammouna
Keyword(s):  
High Temperature ◽  
Ambient Temperature ◽  
Constant Temperature ◽  
Effect Of Temperature ◽  
The Impact

This article reviews the studies on the effect of temperature on the creep of concrete. Indeed, the temperature is one of the most important factors, as its rise leads to an acceleration of creep of concrete and thus an increase in its value compared to concrete under normal temperature. However, creep increases significantly if concrete under load is exposed to a high temperature. Thus, the creep value becomes higher than that of concrete exposed to a constant temperature (of the same level). Unfortunately, some of the codes for predicting creep of concrete (for instance the Eurocode) do not take into account the effect of high temperature on the creep of concrete under load. To clarify the impact of heating concrete under load (on creep) and distinguish it from its effect where it is constant, this study was carried out.

scholarly journals Design of High Temperature Ti–Al–Cr–V Alloys for Maximum Thermodynamic Stability Using Self-Organizing Maps

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 537 ◽  
Author(s):  
Rajesh Jha ◽  
George S. Dulikravich
Keyword(s):  
High Temperature ◽  
Metallic Alloys ◽  
Effect Of Temperature ◽  
Large Dataset ◽  
Self Organizing Maps ◽  
Young’S Moduli ◽  
Starting Point ◽  
Different Temperatures ◽  
Effect Of The Composition ◽  
Self Organizing

Data generated for the Ti–Al–Cr–V system of metallic alloys from our previous publication, where the composition of 102 alloys were computationally Pareto optimized with the objective of simultaneously maximizing the Young’s modulus and minimizing density for a range of temperatures, was the starting point of the current research, where compositions at different temperatures of these alloys were analyzed for phase stability in order to generate new data for compositions and volume fractions of stable phases at various temperatures. This resulted in a large dataset where a lot of data were still missing as all the phases are not stable at a given temperature for all the compositions. The concept of Self-Organizing Maps (SOM) was then applied to determine correlations between alloy compositions, stabilities of desired phases at various temperatures, associated Young’s moduli and densities, and the effect of the composition of phases on these properties. This work should help alloy designers to determine the required chemical composition of a new alloy with reference to the temperature of application of that alloy and see the effect of temperature and composition on stable phases and associated properties of alloys.

scholarly journals Characterization of a thermo-adapted strain of Zymomonas mobilis for ethanol production at high temperature

3 Biotech ◽  
2018 ◽  
Vol 8 (11) ◽  
Author(s):  
Jatupat Samappito ◽  
Mamoru Yamada ◽  
Preekamol Klanrit ◽  
Pornthap Thanonkeo
Keyword(s):  
High Temperature ◽  
Ethanol Production ◽  
Zymomonas Mobilis

The Effect of Temperature Elevation on Microwave-Transmitting Property of Organosilicone-Matrix Radome

2016 ◽  
Vol 848 ◽  
pp. 174-178
Author(s):  
Qian Wang
Keyword(s):  
High Temperature ◽  
Theoretical Model ◽  
Operating Temperature ◽  
Dielectric Spectrum ◽  
Effect Of Temperature ◽  
Matrix Composites ◽  
Temperature Elevation ◽  
Gradient Distribution ◽  
Spectrum Measurement ◽  
Different Temperatures

In this paper, both the permittivity and the microwave transmittance properties of organosilicon-matrix composites under different temperatures have been studied. In order to investigate the reason for the changing of dielectric property, both TGA and high-temperature dielectric spectrum measurement have been carried out. A theoretical model of radome, with a temperature gradient distribution, has been built to analyze the dependence of microwave transmittance property on temperature. Based on the experimental results, we can optimize the effective operating temperature of this kind of organosilicone-matrix composites.

Effect of Temperature on Impact Properties of ZA27 Alloy

2012 ◽  
Vol 476-478 ◽  
pp. 75-80 ◽  
Author(s):  
Li Ping Zhong ◽  
Jia Yong Si ◽  
Zi Qiao Zheng
Keyword(s):  
Impact Toughness ◽  
Fracture Surface ◽  
Impact Energy ◽  
Impact Testing ◽  
Impact Fracture ◽  
Impact Behavior ◽  
Effect Of Temperature ◽  
Za27 Alloy ◽  
Different Temperatures ◽  
The Impact

The impact toughness of ZA27 alloy at different temperatures is investigated by pendulum impact testing. In addition, the morphology of impact fracture surface observed by SEM. The results indicate that impact energy of ZA27 alloy is reduced with the temperature rising when the temperature is lower than 100°C. At 100°C to 200°C, impact energy increase as the temperature rising. And when the temperature reaches to 250°C, impact energy suddenly descend. Impact energy is the highest and reaches to 72.768J at 20°C. At impact fracture surface, it is mostly tear ridges and dimples. The higher the impact energy is, the more obvious the characteristic of tear ridges is. Furthermore, dimples are small and distribute more uniformly. Lower the impact energy, the less distinct of tear ridges. Dimples are larger and deeper, their distribution are not uniform. Impact behavior of material could be evaluated by the width of impact curve. The wider the peak of impact curve, the higher the impact toughness. But impact toughness is worse while peak is narrow.

Research on High Temperature Compression and Creep Properties of Porous Copper Alloy

2016 ◽  
Vol 853 ◽  
pp. 122-126 ◽  
Author(s):  
Li Chen ◽  
Jian Chen ◽  
Wei Li ◽  
Cong Li ◽  
Xiong Fei Li ◽  
...  
Keyword(s):  
High Temperature ◽  
Sintering Process ◽  
Creep Properties ◽  
Powder Sintering ◽  
Porous Copper ◽  
Deformation Stages ◽  
Different Temperatures ◽  
Microscopic Deformation ◽  
Resistance Performance ◽  
The Impact

The powder sintering process is adopted for preparing the porous Cu-35Ni-15Al alloy.The microstructure was observed by using scanning electron microscopy. Mechanical properties were tested and compared at different temperatures and stress conditions. This thesis also studied the impact of stress on creep properties of Cu-35Ni-15Al alloy,The results show there are roughly three deformation stages of high temperature compression deformation.The microscopic deformation was mainly the curved, collapsed and folded holes.The creep resistance performance of porous Cu-35Ni-15Al alloys weakens with the increasing pressure.

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