Screening and Comparative Characterization of Microorganisms from Iranian Soil Samples Showing ω-Transaminase Activity toward a Plethora of Substrates

In this study, soil microorganisms from Iran were screened for ω-transaminase (ω-TA) activity based on growth on minimal media containing (rac)-α-methylbenzylamine (rac-α-MBA) as a sole nitrogen source. Then, for the selection of strains with high enzyme activity, a colorimetric o-xylylendiamine assay was conducted. The most promising strains were identified by 16S rDNA sequencing. Five microorganisms showing high ω-TA activity were subjected to determine optimal conditions for ω-TA activity, including pH, temperature, co-solvent, and the specificity of the ω-TA toward different amine donors and acceptors. Among the five screened microorganisms, Bacillus halotolerans turned out to be the most promising strain: Its cell-free extract showed a highly versatile amino donor spectrum toward aliphatic, aromatic chiral amines and a broad range of pH activity. Transaminase activity also exhibited excellent solvent tolerance, with maximum turnover in the presence of 30% (v/v) DMSO.

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ISOLATION, PURIFICATION, AND CHARACTERIZATION OF LIPASE FROM BACILLUS SP. FROM KITCHEN GREASE

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i6.24955 ◽

2018 ◽

Vol 11 (6) ◽

pp. 224

Author(s):

Jaiganesh R ◽

Jaganathan Mk

Keyword(s):

16S Rdna ◽

Solvent Tolerance ◽

16S Rdna Sequencing ◽

Bacillus Sp ◽

Purification And Characterization ◽

Lipase Enzyme ◽

Sequencing Method ◽

Rdna Sequencing ◽

Solvent Tolerant

Objective: The objective of this work was to isolation, purification and characterization of solvent tolerant lipase from Bacillus sp. The objective of this work was to isolation, purification and characterization of solvent tolerant lipase from Bacillus sp. from kitchen grease for a variety of applications including organic synthetic reactions and preparation of enantiomerically pure pharmaceuticals.Methods: Lipase producing isolates were screened from kitchen grease on a selective medium rhodamine B olive oil agar, and tributyrin agar was used to screen the lipase and esterase producing an organism, respectively. The isolate identified using 16S rDNA sequencing method and enzyme activity was quantitatively assayed. Lipase production was characterized in different conditions.Results: The isolate showed highest lipase activity was which later was identified as Bacillus sp. using 16S rDNA sequencing method. The lipase was purified using ammonium sulfate precipitation. The isolate showed excellent tolerance to methanol, ethanol, acetonitrile, and moderate tolerance to butanol. The increased biomass concentration, maximum production, and activity were achieved at 37°C in 24 h incubation, then gradual reduction in production was observed. The maximum activity of lipase enzyme was obtained at pH between 6 and 9.Conclusion: The isolate produce solvent tolerance lipase enzyme and it can be a promising candidate of solvent tolerance lipase enzyme for variety of industrial applications.

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Applications of Transmission Electron Microscopy in the Characterization of Metal Machinability

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101967 ◽

1968 ◽

Vol 26 ◽

pp. 442-443 ◽

Cited By ~ 1

Author(s):

L.E. Murr ◽

A.B. Draper

Keyword(s):

Electron Microscopy ◽

State Physics ◽

Test Material ◽

Milling Machine ◽

Rotary Table ◽

Solid State Physics ◽

Materials Properties ◽

Transmission Electron ◽

Selection Of

The industrial characterization of the machinability of metals and alloys has always been a very arbitrarily defined property, subject to the selection of various reference or test materials; and the adoption of rather naive and misleading interpretations and standards. However, it seems reasonable to assume that with the present state of knowledge of materials properties, and the current theories of solid state physics, more basic guidelines for machinability characterization might be established on the basis of the residual machined microstructures. This approach was originally pursued by Draper; and our presentation here will simply reflect an exposition and extension of this research.The technique consists initially in the production of machined chips of a desired test material on a horizontal milling machine with the workpiece (specimen) mounted on a rotary table vice. A single cut of a specified depth is taken from the workpiece (0.25 in. wide) each at a new tool location.

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Caracterização da Peneira Média em Clones de Coffea canephora

REVISTA FIMCA ◽

10.37157/fimca.v5i2.58 ◽

2018 ◽

Vol 5 (2) ◽

pp. 28-31

Author(s):

Darlan Darlan Sanches Barbosa Alves ◽

Victor Mouzinho Spinelli ◽

Marcos Santana Moraes ◽

Carolina Augusto De Souza ◽

Rodrigo da Silva Ribeiro ◽

...

Keyword(s):

Genetic Improvement ◽

Block Design ◽

Coffea Canephora ◽

Coffee Production ◽

Randomized Block Design ◽

Significant Difference ◽

The Mean ◽

Four Blocks ◽

Selection Of

Introdução: O estado de Rondônia se destaca como tradicional produtor de café, sendo o segundo maior produtor brasileiro de C. canephora. No melhoramento genético de C. canephora, a seleção de plantas de elevada peneira média está associada à bebida de qualidade superior. Objetivos: O objetivo desse estudo foi avaliar a variabilidade genética de clones de C. canephora para o tamanho dos grãos, mensurado a partir da avaliação da peneira média (PM). Materiais e Métodos: Para isso, foi conduzido ao longo de dois anos agrícolas experimento no campo experimental da Embrapa no município de Ouro Preto do Oeste-RO, para a avaliação da peneira média de 130 genótipos (clones) com características das variedades botânicas Conilon, Robusta e híbridos intervarietais. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições de quatro plantas por parcela. Resultados: Não houve resultados significativos para a interação clones X anos, indicando uma maior consistência no comportamento das plantas ao longo do tempo. Porém foram observadas diferenças significativas para o tamanho dos grãos entre os genótipos avaliados, possibilitando selecionar genótipos superiores. Conclusão: Os genótipos agruparam-se em cinco classes de acordo com o teste de média, subsidiando a caracterização de um gradiente de variabilidade da característica avaliada ABSTRACTIntroduction: Coffea canephora accounts for approximately 35% of the world's coffee production. The state of Rondônia stands out as a traditional coffee producer, being the second largest Brazilian producer of C. canephora. In the classical genetic improvement of C. anephora, the selection of plants of high average sieve is associated with a drink of superior quality. Objectives: The objective of this udy was to evaluate the genetic variability of Coffea canephora clones for the agronomic medium sieve (PM). Materials and Methods: The experiment was conducted in the experimental field of Embrapa, municipality of OuroPreto do Oeste-RO, located at coordinates 10º44'53 "S and 62º12'57". One hundred thirty genotypes (clones) of botanical characteristics Conilon, Robusta and intervarietal hybrids were evaluated in the agricultural years 2013-2014 and 2014-2015. The experimental design was a randomized block design with four blocks and four plants per plot, spacing 3.5 x 1.5 meters between plants. Results: Significant difference was found for the grain size. According to the F test, at 5% probability, the genotypes were grouped into five classes according to the mean test. Conclusion: The results obtained subsidized the characterization of a variability gradient of the evaluated trait.

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Elaboration and Characterization of the Properties of Refractory Cr Base Alloys

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.72.46 ◽

2010 ◽

Vol 72 ◽

pp. 46-52 ◽

Cited By ~ 1

Author(s):

Laurent Royer ◽

Stéphane Mathieu ◽

Christophe Liebaut ◽

Pierre Steinmetz

Keyword(s):

Mechanical Properties ◽

Melting Point ◽

Molten Glass ◽

Energy Production ◽

Creep Properties ◽

Refractory Alloys ◽

Industrial Use ◽

Kinetics Of ◽

Selection Of

For energy production and also for the glass industry, finding new refractory alloys which could permit to increase the process temperatures to 1200°C or more is a permanent challenge. Chromium base alloys can be good candidates, considering the melting point of Cr itself, and also its low corrosion rate in molten glass. Two families of alloys have been studied for this purpose, Cr-Mo-W and Cr-Ta-X alloys (X= Mo, Si..). A finer selection of compositions has been done, to optimize their chemical and mechanical properties. Kinetics of HT oxidation by air, of corrosion by molten glass and also creep properties of several alloys have been measured up to 1250°C. The results obtained with the best alloys (Cr-Ta base) give positive indications as regards the possibility of their industrial use.

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Organelle Genetics in Plants

International Journal of Molecular Sciences ◽

10.3390/ijms22042104 ◽

2021 ◽

Vol 22 (4) ◽

pp. 2104

Author(s):

Pedro Robles ◽

Víctor Quesada

Keyword(s):

Rna Editing ◽

Posttranscriptional Regulation ◽

Genome Engineering ◽

Plant Mitochondria ◽

Plastid Dna ◽

Chloroplast Genomes ◽

Wide Range ◽

Organelle Genetics ◽

Selection Of

Eleven published articles (4 reviews, 7 research papers) are collected in the Special Issue entitled “Organelle Genetics in Plants.” This selection of papers covers a wide range of topics related to chloroplasts and plant mitochondria research: (i) organellar gene expression (OGE) and, more specifically, chloroplast RNA editing in soybean, mitochondria RNA editing, and intron splicing in soybean during nodulation, as well as the study of the roles of transcriptional and posttranscriptional regulation of OGE in plant adaptation to environmental stress; (ii) analysis of the nuclear integrants of mitochondrial DNA (NUMTs) or plastid DNA (NUPTs); (iii) sequencing and characterization of mitochondrial and chloroplast genomes; (iv) recent advances in plastid genome engineering. Here we summarize the main findings of these works, which represent the latest research on the genetics, genomics, and biotechnology of chloroplasts and mitochondria.

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Selection of lactose-adapted cells in vinca minor and Dantura innoxia cultures; location and characterization of β-galactosidase and lactase activities

Plant Science ◽

10.1016/0168-9452(88)90058-1 ◽

1988 ◽

Vol 54 (1) ◽

pp. 83-91 ◽

Cited By ~ 4

Author(s):

O.C. Elavummoottil ◽

S. Duret ◽

A. Vannereau ◽

L. Cosson ◽

J.C. Mestre

Keyword(s):

Vinca Minor ◽

Selection Of

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Preclinical Testing of Radiopharmaceuticals for the Detection and Characterization of Osteomyelitis: Experiences from a Porcine Model

Molecules ◽

10.3390/molecules26144221 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4221

Author(s):

Aage Kristian Olsen Alstrup ◽

Svend Borup Jensen ◽

Ole Lerberg Nielsen ◽

Lars Jødal ◽

Pia Afzelius

Keyword(s):

Animal Model ◽

Animal Models ◽

Porcine Model ◽

Animal Experiments ◽

Radioactive Tracers ◽

The Individual ◽

Selection Of

The development of new and better radioactive tracers capable of detecting and characterizing osteomyelitis is an ongoing process, mainly because available tracers lack selectivity towards osteomyelitis. An integrated part of developing new tracers is the performance of in vivo tests using appropriate animal models. The available animal models for osteomyelitis are also far from ideal. Therefore, developing improved animal osteomyelitis models is as important as developing new radioactive tracers. We recently published a review on radioactive tracers. In this review, we only present and discuss osteomyelitis models. Three ethical aspects (3R) are essential when exposing experimental animals to infections. Thus, we should perform experiments in vitro rather than in vivo (Replacement), use as few animals as possible (Reduction), and impose as little pain on the animal as possible (Refinement). The gain for humans should by far exceed the disadvantages for the individual experimental animal. To this end, the translational value of animal experiments is crucial. We therefore need a robust and well-characterized animal model to evaluate new osteomyelitis tracers to be sure that unpredicted variation in the animal model does not lead to a misinterpretation of the tracer behavior. In this review, we focus on how the development of radioactive tracers relies heavily on the selection of a reliable animal model, and we base the discussions on our own experience with a porcine model.

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Characterization of efficient xylanases from industrial-scale pulp and paper wastewater treatment microbiota

AMB Express ◽

10.1186/s13568-020-01178-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jia Wang ◽

Jiawei Liang ◽

Yonghong Li ◽

Lingmin Tian ◽

Yongjun Wei

Keyword(s):

Wastewater Treatment ◽

Xylanase Activity ◽

Pulp And Paper ◽

Optimal Conditions ◽

Paper Wastewater ◽

Termite Hindgut ◽

Uncultured Microorganisms ◽

Metagenomic Approach ◽

Gh10 Family

AbstractXylanases are widely used enzymes in the food, textile, and paper industries. Most efficient xylanases have been identified from lignocellulose-degrading microbiota, such as the microbiota of the cow rumen and the termite hindgut. Xylanase genes from efficient pulp and paper wastewater treatment (PPWT) microbiota have been previously recovered by metagenomics, assigning most of the xylanase genes to the GH10 family. In this study, a total of 40 GH10 family xylanase genes derived from a certain PPWT microbiota were cloned and expressed in Escherichia coli BL21 (DE3). Among these xylanase genes, 14 showed xylanase activity on beechwood substrate. Two of these, PW-xyl9 and PW-xyl37, showed high activities, and were purified to evaluate their xylanase properties. Values of optimal pH and temperature for PW-xyl9 were pH 7 and 60 ℃, respectively, while those for PW-xyl37 were pH 7 and 55 ℃, respectively; their specific xylanase activities under optimal conditions were 470.1 U/mg protein and 113.7 U/mg protein, respectively. Furthermore, the Km values of PW-xyl9 and PW-xyl37 were determined as 8.02 and 18.8 g/L, respectively. The characterization of these two xylanases paves the way for potential application in future pulp and paper production and other industries, indicating that PPWT microbiota has been an undiscovered reservoir of efficient lignocellulase genes. This study demonstrates that a metagenomic approach has the potential to screen efficient xylanases of uncultured microorganisms from lignocellulose-degrading microbiota. In a similar way, other efficient lignocellulase genes might be identified from PPWT treatment microbiota in the future.

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Characterization of Carrier Phase-Based Positioning in Real-World Jamming Conditions

Remote Sensing ◽

10.3390/rs13142680 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2680

Author(s):

Søren Skaarup Larsen ◽

Anna B. O. Jensen ◽

Daniel H. Olesen

Keyword(s):

Real World ◽

Carrier Phase ◽

Reference Station ◽

Baseline Length ◽

Dual Frequency ◽

Positioning Accuracy ◽

The Impact ◽

Single Versus ◽

Selection Of

GNSS signals arriving at receivers at the surface of the Earth are weak and easily susceptible to interference and jamming. In this paper, the impact of jamming on the reference station in carrier phase-based relative baseline solutions is examined. Several scenarios are investigated in order to assess the robustness of carrier phase-based positioning towards jamming. Among others, these scenarios include a varying baseline length, the use of single- versus dual-frequency observations, and the inclusion of the Galileo and GLONASS constellations to a GPS only solution. The investigations are based on observations recorded at physical reference stations in the Danish TAPAS network during actual jamming incidents, in order to realistically evaluate the impact of real-world jamming on carrier phase-based positioning accuracy. The analyses performed show that, while there are benefits of using observations from several frequencies and constellations in positioning solutions, special care must be taken in solution processing. The selection of which GNSS constellations and observations to include, as well as when they are included, is essential, as blindly adding more jamming-affected observations may lead to worse positioning accuracy.

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Presenting a Semi-Automatic, Statistically-Based Approach to Assess the Sharpness Level of Optical Images from Natural Targets via the Edge Method. Case Study: The Landsat 8 OLI–L1T Data

Remote Sensing ◽

10.3390/rs13081593 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1593

Author(s):

Luca Cenci ◽

Valerio Pampanoni ◽

Giovanni Laneve ◽

Carla Santella ◽

Valentina Boccia

Keyword(s):

Landsat 8 ◽

Image Sharpness ◽

Optical Images ◽

Data Quality Assessment ◽

Relevant Role ◽

Edge Method ◽

Selection Of ◽

Statistical Criteria

Developing reliable methodologies of data quality assessment is of paramount importance for maximizing the exploitation of Earth observation (EO) products. Among the different factors influencing EO optical image quality, sharpness has a relevant role. When implementing on-orbit approaches of sharpness assessment, such as the edge method, a crucial step that strongly affects the final results is the selection of suitable edges to use for the analysis. Within this context, this paper aims at proposing a semi-automatic, statistically-based edge method (SaSbEM) that exploits edges extracted from natural targets easily and largely available on Earth: agricultural fields. For each image that is analyzed, SaSbEM detects numerous suitable edges (e.g., dozens-hundreds) characterized by specific geometrical and statistical criteria. This guarantees the repeatability and reliability of the analysis. Then, it implements a standard edge method to assess the sharpness level of each edge. Finally, it performs a statistical analysis of the results to have a robust characterization of the image sharpness level and its uncertainty. The method was validated by using Landsat 8 L1T products. Results proved that: SaSbEM is capable of performing a reliable and repeatable sharpness assessment; Landsat 8 L1T data are characterized by very good sharpness performance.

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