scholarly journals Application of Adaptive Evolution to Improve the Stability of Bacteriophages during Storage

Viruses ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 423
Author(s):  
Kelvin K. Kering ◽  
Xiaoxu Zhang ◽  
Raphael Nyaruaba ◽  
Junping Yu ◽  
Hongping Wei
Keyword(s):  
Heat Treatment ◽  
Adaptive Evolution ◽  
Antibacterial Agents ◽  
Critical Factor ◽  
Wild Type ◽  
The Stability ◽  
Tubular Proteins ◽  
Thermal Stability Of ◽  
General Method

Phage stability is important for the successful application of bacteriophages as alternative antibacterial agents. Considering that temperature is a critical factor in phage stability, this study aimed to explore the possibility of improving long-term phage stability through adaptive evolution to elevated temperature. Evolution of three wild-type ancestral phages (Myoviridae phage Wc4 and Podoviridae phages CX5 and P-PSG-11) was induced by subjecting the phages to heat treatment at 60 °C for five cycles. The adapted phages showed better stability than the wild-type ancestral phages when subjected to heat treatment at 60 °C for 1 h and after 60 days of storage at 37 °C. However, the adapted phages could not withstand thermal treatment at 70 °C for 1 h. The infectivity and the lytic properties of the phages were not changed by the evolution process. Whole-genome sequencing revealed that single substitutions in the tail tubular proteins were the only changes observed in the genomes of the adapted phages. This study demonstrates that adaptive evolution could be used as a general method for enhancing the thermal stability of phages without affecting their lytic activity. Sequencing results showed that bacteriophages may exist as a population with minor heterogeneous mutants, which might be important to understand the ecology of phages in different environments.

scholarly journals Стабильность функциональных характеристик прозрачных электродов на основе трехслойной структуры ZnO : Ga/Ag/ZnO : Ga

2022 ◽  
Vol 48 (2) ◽  
pp. 51
Author(s):  
А.Ш. Асваров ◽  
А.К. Ахмедов ◽  
А.Э. Муслимов ◽  
В.М. Каневский
Keyword(s):  
Heat Treatment ◽  
Thermal Stability ◽  
Room Temperature ◽  
Layer Structure ◽  
Visible Range ◽  
Practical Application ◽  
Transparent Conducting ◽  
Average Transmittance ◽  
The Stability

Since to the stability of the functional properties of a transparent conducting three-layer structure ZnO:Ga/Ag/ZnO:Ga is important for practical application, we studied its long-term durability and thermal stability in air environment. It has been demonstrated that after prolonged interaction with the air environment at room temperature (~ 1000 h) and further heat treatment in air at temperatures up to 450 ° C (up to 10 h), the three-layer structure retains its integrity and is characterized by a low sheet resistance Rs = 2.8 Ω/sq at average transmittance in the visible range Tav of 82.1%.

Improve Stability of Dicalcium Silicate/Zirconia Composite Coatings by Post-Spraying Heat Treatment

2005 ◽  
Vol 107 ◽  
pp. 141-144 ◽  
Author(s):  
Youtao Xie ◽  
Paul K. Chu ◽  
Xuan Yong Liu ◽  
Chuan Xian Ding
Keyword(s):  
Heat Treatment ◽  
Composite Coatings ◽  
Immersion Test ◽  
Dicalcium Silicate ◽  
Test Results ◽  
Long Term Stability ◽  
The Stability ◽  
Plasma Sprayed ◽  
Sprayed Coatings

The long-term stability of plasma-sprayed dicalcium silicate (C2S) composite coatings is determined by the phase composition, crystallinity, and other properties. Zirconia reinforcement and post-spraying heat treatment are applied to C2S coatings simultaneously in this work. The stability of the coating increases evidently by reinforcement with 70wt% zirconia and heat treatment at 800oC for 4 hours. SEM reveals that the smooth glassy surface of the as-sprayed coatings is replaced by randomly dispersed crystals. Tris-HCl immersion test results show that the dissolution rate of the composite coatings decreases after the heat treatment.

The Thermal Stability of a Single-Grain Mg-Zn-Y Icosahedral Quasicrystal

2000 ◽  
Vol 643 ◽  
Author(s):  
Z.P. Luo ◽  
Y.L. Tang ◽  
D.J. Miller ◽  
M.J. Kramer ◽  
I.R. Fisher ◽  
...  
Keyword(s):  
Golden Ratio ◽  
Lattice Parameter ◽  
Icosahedral Quasicrystal ◽  
Face Centered Cubic ◽  
Single Grain ◽  
Face Centered ◽  
The Stability ◽  
Mg Content ◽  
Thermal Stability Of

AbstractThe stability of the Mg-Zn-Y icosahedral quasicrystal (IQC) has been studied by long-term annealing of a single grain IQC in quartz tubes. Decomposition of the IQC was observed after annealing at high temperatures (T≥773 K) sealed in Ar. During the decomposition process, the quasilattice parameter aR was found to decrease, associated with a decrease in Mg content of the IQC phase as confirmed by quantitative x-ray energy dispersive spectroscopy analyses. In addition, a new cubic approximant has been found in the annealed samples. This cubic approximant has a face-centered cubic (fcc) structure with lattice parameter of a = 1.276 nm, which is about (1/τ) times smaller than that of the fcc W'-(MgZnY) with a = 2.05 nm reported previously (where τ is the golden ratio).

scholarly journals Rational Protein Engineering to Increase the Activity and Stability of IsPETase Using the PROSS Algorithm

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3884
Author(s):  
Andrew Rennison ◽  
Jakob R. Winther ◽  
Cristiano Varrone
Keyword(s):  
Thermal Stability ◽  
Enzyme Stability ◽  
Fold Increase ◽  
Wild Type ◽  
Bioinformatic Tools ◽  
Mild Conditions ◽  
Degradation Activity ◽  
Packaging Industry ◽  
The Stability ◽  
Thermal Stability Of

Polyethylene terephthalate (PET) is the most widely used polyester plastic, with applications in the textile and packaging industry. Currently, re-moulding is the main path for PET recycling, but this eventually leads to an unsustainable loss of quality; thus, other means of recycling are required. Enzymatic hydrolysis offers the possibility of monomer formation under mild conditions and opens up alternative and infinite recycling paths. Here, IsPETase, derived from the bacterium Ideonella sakaiensis, is considered to be the most active enzyme for PET degradation under mild conditions, and although several studies have demonstrated improvements to both the stability and activity of this enzyme, stability at even moderate temperatures is still an issue. In the present study, we have used sequence and structure-based bioinformatic tools to identify mutations to increase the thermal stability of the enzyme so as to increase PET degradation activity during extended hydrolysis reactions. We found that amino acid substitution S136E showed significant increases to activity and stability. S136E is a previously unreported variant that led to a 3.3-fold increase in activity relative to wild type.

SANS study on the stability of oxide nanoparticles in long-term thermally aged 9Cr-ODS steel

2021 ◽  
Author(s):  
Peng-Lin Gao ◽  
Jian Gong ◽  
Qiang Tian ◽  
Gung-Ai Sun ◽  
Hai-Yang Yan ◽  
...  
Keyword(s):  
Oxide Dispersion Strengthened ◽  
Oxide Nanoparticles ◽  
Electron Backscattered Diffraction ◽  
Excellent Thermal Stability ◽  
Ods Steel ◽  
Transmission Electron ◽  
Hardness Tests ◽  
The Stability ◽  
Thermal Stability Of

Abstract A 9Cr-oxide dispersion strengthened (ODS) steel was thermally aged at 873 K for up to 5000 hours. The size distribution and chemical composition of the dispersed oxide nanoparticles were analyzed by small angle neutron scattering (SANS) method under magnetic field. Combined with transmission electron microscopy (TEM), Vickers micro-hardness tests and electron backscattered diffraction (EBSD) measurements, all the results showed that the thermal treatment had little or no effect on the size distributions and volume fractions of the oxide nanoparticles in the ferromagnetic matrix, which suggested excellent thermal stability of the 9Cr-ODS steel.

Thermal Stability of Ti-6Al-4V Alloy with Carbon Content

2015 ◽  
Vol 226 ◽  
pp. 23-28
Author(s):  
Agnieszka Szkliniarz
Keyword(s):  
Carbon Content ◽  
Operating Temperature ◽  
Solution Treatment ◽  
Aging Treatment ◽  
Hardness Test ◽  
Two Phase ◽  
Microstructure Stability ◽  
The Stability ◽  
Thermal Stability Of

In the paper, the effect of long-term annealing (to 500 h) on the microstructure and hardness of two-phase titanium alloy which represent group of α+β (Ti-6Al-4V) with 0.7 wt. % carbon content was present. The stability of microstructure after long-term annealing was conducted to alloys in hardening state (after solution treatment and aging). Annealing was carried out at a temperature above the operating temperature of commercial titanium alloys without carbon content. The analysis of changes in the microstructure at research range of annealing time indicates its stability, which was confirmed by hardness test of investigated alloys. For comparison to Ti-6Al-4V-0.7C alloy, the microstructure stability research at 420oC was conducted for classical alloy contain no carbon. This alloy was previously subject solution and aging treatment under the same conditions as tested alloy.

scholarly journals Effects of high mechanical treatment and long-term annealing on crystal structure and thermal stability of Ti2O3 nanocrystals

RSC Advances ◽  
2020 ◽  
Vol 10 (43) ◽  
pp. 25717-25720
Author(s):  
Albina A. Valeeva ◽  
Svetlana Z. Nazarova ◽  
Hartmuth Schröttner ◽  
Evgeny Yu. Gerasimov ◽  
Andrey A. Rempel
Keyword(s):  
Crystal Structure ◽  
Thermal Stability ◽  
Magnetic Susceptibility ◽  
Mechanical Treatment ◽  
High Energy ◽  
High Energy Milling ◽  
The Stability ◽  
Thermal Stability Of

The effect of high-energy milling and long-term annealing on the stability of Ti2O3 nanocrystals was studied using a magnetic susceptibility method.

scholarly journals miR-146a attenuates apoptosis and modulates autophagy by targeting TAF9b/P53 pathway in doxorubicin-induced cardiotoxicity

2019 ◽  
Vol 10 (9) ◽  
Author(s):  
Jian-An Pan ◽  
Yong Tang ◽  
Jian-Ying Yu ◽  
Hui Zhang ◽  
Jun-Feng Zhang ◽  
...  
Keyword(s):  
Protective Factor ◽  
Low Dose ◽  
Tata Binding Protein ◽  
Wild Type ◽  
P53 Pathway ◽  
The Stability ◽  
Dose Dependent

Abstract Clinical therapy of doxorubicin (DOX) is limited due to its cardiotoxicity. miR-146a was proved as a protective factor in many cardiovascular diseases, but its role in chronic DOX-induced cardiotoxicity is unclear. The objective of this study was to demonstrate the role of miR-146a in low-dose long-term DOX-induced cardiotoxicity. Experiments have shown that DOX intervention caused a dose-dependent and time-dependent cardiotoxicity involving the increased of apoptosis and dysregulation of autophagy. The cardiotoxicity was inhibited by overexpressed miR-146a and was more severe when miR-146a was downgraded. Further research proved that miR-146a targeted TATA-binding protein (TBP) associated factor 9b (TAF9b), a coactivator and stabilizer of P53, indirectly destroyed the stability of P53, thereby inhibiting apoptosis and improving autophagy in cardiomyocytes. Besides, miR-146a knockout mice were used for in vivo validation. In the DOX-induced model, miR-146a deficiency made it worse whether in cardiac function, cardiomyocyte apoptosis or basal level of autophagy, than wild-type. In conclusion, miR-146a partially reversed the DOX-induced cardiotoxicity by targeting TAF9b/P53 pathway to attenuate apoptosis and adjust autophagy levels.

scholarly journals Simulation of the Interactions of Arginine with Wild-Type GALT Enzyme and the Classic Galactosemia-Related Mutant p.Q188R by a Computational Approach

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 6061
Author(s):  
Anna Verdino ◽  
Gaetano D’Urso ◽  
Carmen Tammone ◽  
Bernardina Scafuri ◽  
Lucrezia Catapano ◽  
...  
Keyword(s):  
Amino Acid ◽  
Wild Type ◽  
Computational Simulations ◽  
Galactose Metabolism ◽  
Classic Galactosemia ◽  
The Third ◽  
Clinical Level ◽  
Human Enzyme ◽  
The Stability

Classic galactosemia is an inborn error of metabolism associated with mutations that impair the activity and the stability of galactose-1-phosphate uridylyltransferase (GALT), catalyzing the third step in galactose metabolism. To date, no treatments (including dietary galactose deprivation) are able to prevent or alleviate the long-term complications affecting galactosemic patients. Evidence that arginine is able to improve the activity of the human enzyme expressed in a prokaryotic model of classic galactosemia has induced researchers to suppose that this amino acid could act as a pharmacochaperone, but no effects were detected in four galactosemic patients treated with this amino acid. Given that no molecular characterizations of the possible effects of arginine on GALT have been performed, and given that the samples of patients treated with arginine are extremely limited for drawing definitive conclusions at the clinical level, we performed computational simulations in order to predict the interactions (if any) between this amino acid and the enzyme. Our results do not support the possibility that arginine could function as a pharmacochaperone for GALT, but information obtained by this study could be useful for identifying, in the future, possible pharmacochaperones for this enzyme.

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