Study of the Enzymatic Capacity of Kluyveromyces marxianus for the Synthesis of Esters

Recently, biotechnological opportunities have been found in non-Saccharomyces yeasts because they possess metabolic characteristics that lead to the production of compounds of interest. It has been observed that Kluyveromyces marxianus has a great potential in the production of esters, which are aromatic compounds of industrial importance. The genetic bases that govern the synthesis of esters include a large group of enzymes, among which the most important are alcohol acetyl transferases (AATases) and esterases (AEATases), and it is known that some are present in K. marxianus, because it has genetic characteristics like S. cerevisiae. It also has a physiology suitable for biotechnological use since it is the eukaryotic microorganism with the fastest growth rate and has a wide range of thermotolerance with respect to other yeasts. In this work, the enzymatic background of K. marxianus involved in the synthesis of esters is analyzed, based on the sequences reported in the NCBI database.

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Regioselective Functionalization of N-Fused Heteroaromatics via FeCl3-Catalyzed Nucleophilic Addition to Activated N-Heterocycles

Synthesis ◽

10.1055/s-0040-1705985 ◽

2020 ◽

Author(s):

Ikyon Kim ◽

Sung June Kim ◽

Sunhee Lee

Keyword(s):

Aromatic Compounds ◽

Nucleophilic Addition ◽

Chemical Space ◽

Wide Range ◽

Regioselective Functionalization

AbstractBroadening of nitrogen-fused heteroaromatic chemical space such as indolizine and pyrrolo[1,2-a]pyrazine was achieved via FeCl3-catalyzed nucleophilic addition of these N-fused aromatic compounds to a wide range of azolinium systems generated in situ, leading to novel N-fused heteroaromatic scaffolds with dearomatized N-heterocyclic substituents regioselectively. Nucleophilic addition of indolizines and pyrrolo[1,2-a]pyrazines mainly occurred at the C1 position of the isoquinoliniums and at the C4 site of the quinoliniums.

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Consumer Neuroscience as a Tool to Monitor the Impact of Aromas on Consumer Emotions When Buying Food

Applied Sciences ◽

10.3390/app11156692 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6692

Author(s):

Jakub Berčík ◽

Katarína Neomániová ◽

Jana Gálová ◽

Anna Mravcová

Keyword(s):

Aromatic Compounds ◽

Competitive Environment ◽

Retail Operations ◽

Consumer Neuroscience ◽

Wide Range ◽

Consumer Emotions ◽

Affective Processes ◽

Effective Selection ◽

The Subject ◽

The Impact

Building a unique USP sales argument (unique selling proposition) through various forms of in-store communication comes to the fore in a challenging competitive environment. Scent as a means to influence the purchase of goods or services has a long history, however, aromachology as field of in-store communication is a matter of the present. This new trend, the importance and use of which has grown in recent years, is the subject of a wide range of research. In order to increase the efficiency of these elements, it is necessary to familiarise ourselves with the factors that affect the customer, whether that be consciously or unconsciously. Consumer neuroscience is addressed in this area. This paper deals with the comprehensive interdisciplinary investigation of the impact of selected aromatic compounds on consumer cognitive and affective processes as well as assessing the effectiveness of their implementation in food retail operations. At the end of the paper, we recommend options for the effective selection and implementation of aromatisation of different premises, by which the retailer can achieve not only a successful form of in-store communication, but also an increase the retail turnover of the store.

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Phylogeographic Investigation of an Endangered Longhorn Beetle, Callipogon relictus (Coleoptera: Cerambycidae), in Northeast Asia: Implications for Future Restoration in Korea

Insects ◽

10.3390/insects12060555 ◽

2021 ◽

Vol 12 (6) ◽

pp. 555

Author(s):

Ji-Hyoun Kang ◽

Dae-Am Yi ◽

Alexander V. Kuprin ◽

Chang-Do Han ◽

Yeon-Jae Bae

Keyword(s):

South Korea ◽

Mitochondrial Gene ◽

Northeast Asia ◽

Haplotype Network ◽

Conservation Strategies ◽

Genetic Characteristics ◽

Linear Pattern ◽

Wide Range ◽

Longhorn Beetle ◽

High Level

The longhorn beetle, Callipogon (Eoxenus) relictus Semenov, is the only remnant species found in the Palearctic region, while all other Callipogon species are distributed mainly in Central America and partly in South America. This species has been placed in the first category (as ‘critically endangered’) of the Red Data Book in Russia and designated as one of the top-priority target species among all endangered invertebrate species for restoration in South Korea since 2006. Although its restricted distribution in Northeast Asia with a high conservational value has been highlighted, genetic features of C. relictus from different geographic regions remain unexplored. We first investigated the level of genetic diversity and phylogeographic patterns of C. relictus to evaluate the current conservational status and the feasibility of the implementation of a restoration program. The average genetic divergence of mitochondrial gene COI based on Kimura-2-parameter distance among the four regions in Russia, China, North Korea, and South Korea was 2.2%, which lies within the range of intraspecific levels. However, two separate clades with 3.8% divergence were identified, despite no geographical clustering of haplotypes. The linear pattern of the haplotype network with a high level of haplotype and nucleotide diversities suggests that the wide range of currently fragmented populations might be the remnant of genetically diverse populations in the past. This study will provide crucial information on the genetic characteristics and phylogeographic history of C. relictus, which will help to establish conservation strategies for this cherished insect species in Northeast Asia.

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Dependence of Microstructures and Mechanical Properties on the Growth Rate and Composition in Directionally Solidified Mg-Gd Alloys

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.327.82 ◽

2022 ◽

Vol 327 ◽

pp. 82-97

Author(s):

He Qin ◽

Guang Yu Yang ◽

Shi Feng Luo ◽

Tong Bai ◽

Wan Qi Jie

Keyword(s):

Mechanical Properties ◽

Growth Rate ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

Dendritic Structure ◽

Directionally Solidified ◽

Dendrite Morphology ◽

Microstructural Parameters ◽

Wide Range ◽

Microstructures And Mechanical Properties

Microstructures and mechanical properties of directionally solidified Mg-xGd (5.21, 7.96 and 9.58 wt.%) alloys were investigated at a wide range of growth rates (V = 10-200 μm/s) under the constant temperature gradient (G = 30 K/mm). The results showed that when the growth rate was 10 μm/s, different interface morphologies were observed in three tested alloys: cellular morphology for Mg-5.21Gd alloy, a mixed morphology of cellular structure and dendritic structure for Mg-7.96Gd alloy and dendrite morphology for Mg-9.58Gd alloy, respectively. Upon further increasing the growth rate, only dendrite morphology was exhibited in all experimental alloys. The microstructural parameters (λ1, λ2) decreased with increasing the growth rate for all the experimental alloy, and the measured λ1 and λ2 values were in good agreement with Trivedi model and Kattamis-Flemings model, respectively. Vickers hardness and the ultimate tensile strength increased with the increase of the growth rate and Gd content, while the elongation decreased gradually. Furthermore, the relationships between the hardness, ultimate tensile strength, the growth rate and the microstructural parameters were discussed and compared with the previous experimental results.

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Study of the low cycle fatigue of 12Cr18Ni10Ti steel based on fractal analysis and artificial intelligence approaches

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2021-87-9-59-67 ◽

2021 ◽

Vol 87 (9) ◽

pp. 59-67

Author(s):

A. A. Khlybov ◽

Yu. G. Kabaldin ◽

M. S. Anosov ◽

D. A. Ryabov ◽

D. A. Shatagin

Keyword(s):

Neural Network ◽

Growth Rate ◽

Fractal Dimension ◽

Low Temperatures ◽

Main Crack ◽

Fatigue Loading ◽

Wide Range ◽

Lower Temperature ◽

Number Of Cycles ◽

Dimension Index

The evolution of the structure and assessment of the age limit of steel 12Cr18Ni10Ti upon fatigue loading is considered using neural network modeling and approaches of fractal analysis of the microstructure. An algorithm for processing images of the microstructures has been developed to improve their quality. An indicator of the fractal dimension of the image is used as a quantitative indicator for assessing the evolution of the microstructure of the surface metal layer. A quantitative assessment of the structures at different stress amplitudes is carried out in a wide range of low temperatures using the fractal dimension index. Correlation of the fractal dimension index with the run of the sample material is shown. The appearance of the main crack was observed in the range of 0.7 - 0.8 from the number of cycles to failure, after which the crack growth rate increased. At a lower temperature, the main crack is formed later, but further loading results in a higher crack growth rate. Formation of the secondary phases in austenitic steel at a lower temperature occurred at earlier stages than that at a temperature of t = +20°C, which led to hardening of the material. An artificial neural network (ANN) has been developed and trained for assessing structural changes in metal proceeding from the fractal dimensionality of the microstructure images at different stages of fatigue loading. The developed neural network made it possible to estimate with a sufficiently high accuracy the number of cycles before damage of the sample and the residual life of the material. Thus, the developed ANN can be used to assess the current state of the material in a wide range of low temperatures.

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Virulence and Metabolic Characteristics of Salmonella enterica Serovar Enteritidis Strains with DifferentsefDVariants in Hens

Applied and Environmental Microbiology ◽

10.1128/aem.00852-12 ◽

2012 ◽

Vol 78 (18) ◽

pp. 6405-6412 ◽

Cited By ~ 6

Author(s):

Cesar A. Morales ◽

Jean Guard ◽

Roxana Sanchez-Ingunza ◽

Devendra H. Shah ◽

Mark Harrison

Keyword(s):

Salmonella Enterica ◽

Egg Production ◽

The Body ◽

Wild Type ◽

Salmonella Enterica Serovar Enteritidis ◽

Blood Calcium ◽

Content Type ◽

Metabolic Characteristics ◽

Wide Range ◽

Metabolic Properties

ABSTRACTSalmonella entericaserovar Enteritidis is one of a fewSalmonella entericaserotypes that has SEF14 fimbriae encoded by thesefoperon, which consists of 4 cotranscribed genes,sefABCD, regulated bysefR. A parental strain was used to construct asefDmutant and its complement, and all 3 strains were compared for gene expression, metabolic properties, and virulence characteristics in hens. Transcription ofsefDby wild type was suppressed at 42°C and absent for the mutant under conditions where the complemented mutant had 103times higher transcription. Growth of the complemented mutant was restricted in comparison to that of the mutant and wild type. Hens infected with the wild type and mutant showed decreased blood calcium and egg production, but infection with the complemented mutant did not. Thus, the absence ofsefDcorrelated with increased metabolic capacity and enhanced virulence of the pathogen. These results suggest that any contribution thatsefDmakes to egg contamination is either unknown or would be limited to early transmission from the environment to the host. Absence ofsefD, either through mutation or by suppression of transcription at the body temperature of the host, may contribute to the virulence ofSalmonella entericaby facilitating growth on a wide range of metabolites.

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Latitude and Relative Growth in the Razor Clam, Siliqua Patula

Journal of Experimental Biology ◽

10.1242/jeb.8.3.228 ◽

1931 ◽

Vol 8 (3) ◽

pp. 228-249

Author(s):

F. W. WEYMOUTH ◽

H. C. McMILLIN ◽

WILLIS H. RICH

Keyword(s):

Growth Rate ◽

Life Span ◽

Relative Growth Rate ◽

Growth Data ◽

Natural Conditions ◽

Relative Growth ◽

Absolute Growth Rate ◽

Mathematical Expressions ◽

Wide Range ◽

Absolute Growth

1. The present paper is a study of the growth of a clam (Siliqua patula) under natural conditions and over a wide range of latitude. 2. Various constants derived from the growth data are compared for the different localities. For this species, over the range considered, growth in the southern localities as compared with the northern is initially more rapid but less sustained, leads to a smaller total length and is associated with a shorter life span. 3. Reasons are presented for considering the relative growth-rate as a particularly significant constant leading to more sound biological conclusions than the use of the absolute growth-rate. 4. On the basis of the relative growth-rate, current mathematical expressions for the course of growth are discussed and a formula used which emphasises Minot's conception of a growth-rate constantly declining with age. This expression L = Be-ce-ce-kt, in which L = length at time t, e = base of natural logarithms, and B, c and k are constants, is found to graduate the extensive data in clam growth with significant accuracy.

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Microbial community composition is linked to Sphagnum acclimation to warming

10.5194/egusphere-egu21-13734 ◽

2021 ◽

Author(s):

Tatjana Živković ◽

Alyssa A Carell ◽

Gustaf Granath ◽

Mats B Nilsson ◽

Manuel Helbig ◽

...

Keyword(s):

Growth Rate ◽

Host Plant ◽

Climate Warming ◽

Elevated Temperatures ◽

Critical Role ◽

Temperature Acclimation ◽

Microbial Interactions ◽

Germ Free ◽

Wide Range ◽

Thermal Origin

Peatlands store about third of the terrestrial carbon (C) and exert long-term climate cooling. Dominant plant genera in acidic peatlands, Sphagnum mosses, are main contributors to net primary productivity. Through associative relationships with diverse microbial organisms (microbiome), Sphagnum mosses control major biogeochemical processes, namely uptake, storage and potential release of carbon and nitrogen. Climate warming is expected to negatively impact C accumulation in peatlands and alter nutrient cycling, however Sphagnum-dominated peatland resilience to climate warming may depend on Sphagnum-microbiome associations. The ability of the microbiome to rapidly acclimatize to warming may aid Sphagnum exposed to elevated temperatures through host-microbiome acquired thermotolerance. We investigated the role of the microbiome on Sphagnum&#8217;s ability to acclimate to elevated temperatures using a microbiome-transfer approach to test: a) whether the thermal origin of the microbiome influences acclimation of Sphagnum growth and b) if microbial benefits to Sphagnum growth depend on donor Sphagnum species.&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Using a full-factorial design, microbiomes were separated from Sphagnum &#8220;donor&#8221; species from four different peatlands across a wide range of thermal environments (11.4-27&#176;C). The microbiomes were transferred onto germ-free &#8220;recipient&#8221; Sphagnum species in the laboratory and exposed to a range of experimental temperatures (8.5 &#8211; 26.5&#176;C) for growth analysis over 4 weeks.&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Normalized growth rates were maximized for plants that received a microbiome from a matched &#8220;donor&#8221; and with a similar origin temperature (&#916;Ttreatment-origin: 0.3&#177;0.9&#176;C [&#177;standard error], p = 0.73). For non-matched &#8220;donor-recipient&#8221; Sphagnum pairs, &#916;Ttreatment-origin was slightly negative with -4.1&#177;2.1&#176;C (p = 0.06). The largest growth rate of the &#8220;recipient&#8221; was measured when grown with a microbiome from a matching &#8220;donor&#8221; Sphagnum species and was 252% and 48% larger than the maximum growth rate of the germ-free Sphagnum and the non-matched &#8220;donor-recipient&#8221; Sphagnum pairs, respectively.&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Our results suggest that the composition of the Sphagnum microbiome plays a critical role in host plant temperature acclimation. We found that microbially-provided benefits to the host plant were most pronounced when: 1) the thermal origin of the microbiome is similar to experimental temperatures, and 2) when donor and recipient Sphagnum species are the same. Together, these results suggest that Sphagnum temperature acclimation can be modulated, in part, by microbial interactions and may potentially play a role in peatland resilience to climate warming.

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Novel Polymorphisms and Genetic Characteristics of the Prion Protein Gene (PRNP) in Dogs—A Resistant Animal of Prion Disease

International Journal of Molecular Sciences ◽

10.3390/ijms21114160 ◽

2020 ◽

Vol 21 (11) ◽

pp. 4160 ◽

Cited By ~ 1

Author(s):

Dong-Ju Kim ◽

Yong-Chan Kim ◽

An-Dang Kim ◽

Byung-Hoon Jeong

Keyword(s):

Hydrogen Bonds ◽

Prion Protein ◽

Protein Gene ◽

Direct Sequencing ◽

Transmissible Spongiform Encephalopathies ◽

Prion Protein Gene ◽

Genetic Characteristics ◽

Aggregation Propensity ◽

Wide Range ◽

The Impact

Transmissible spongiform encephalopathies (TSEs) have been reported in a wide range of species. However, TSE infection in natural cases has never been reported in dogs. Previous studies have reported that polymorphisms of the prion protein gene (PRNP) have a direct impact on the susceptibility of TSE. However, studies on polymorphisms of the canine PRNP gene are very rare in dogs. We examined the genotype, allele, and haplotype frequencies of canine PRNP in 204 dogs using direct sequencing and analyzed linkage disequilibrium (LD) using Haploview version 4.2. In addition, to evaluate the impact of nonsynonymous polymorphisms on the function of prion protein (PrP), we carried out in silico analysis using PolyPhen-2, PROVEAN, and PANTHER. Furthermore, we analyzed the structure of PrP and hydrogen bonds according to alleles of nonsynonymous single nucleotide polymorphisms (SNPs) using the Swiss-Pdb Viewer program. Finally, we predicted the impact of the polymorphisms on the aggregation propensity of dog PrP using AMYCO. We identified a total of eight polymorphisms, including five novel SNPs and one insertion/deletion polymorphism, and found strong LDs and six major haplotypes among eight polymorphisms. In addition, we identified significantly different distribution of haplotypes among eight dog breeds, however, the kinds of identified polymorphisms were different among each dog breed. We predicted that p.64_71del HGGGWGQP, Asp182Gly, and Asp182Glu polymorphisms can impact the function and/or structure of dog PrP. Furthermore, the number of hydrogen bonds of dog PrP with the Glu182 and Gly182 alleles were predicted to be less than those with the Asp182 allele. Finally, Asp163Glu and Asp182Gly showed more aggregation propensity than wild-type dog PrP. These results suggest that nonsynonymous SNPs, Asp182Glu and Asp182Gly, can influence the stability of dog PrP and confer the possibility of TSE infection in dogs.

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Magnetic Rayleigh–Taylor instability at a contact discontinuity with an oblique magnetic field

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936490 ◽

2020 ◽

Vol 634 ◽

pp. A96

Author(s):

E. Vickers ◽

I. Ballai ◽

R. Erdélyi

Keyword(s):

Magnetic Field ◽

Growth Rate ◽

Dispersion Relation ◽

Contact Discontinuity ◽

Homogeneous Magnetic Field ◽

Taylor Instability ◽

Wide Range ◽

Rayleigh Taylor Instability ◽

The Magnetic Field ◽

Theoretical Results

Aims. We investigate the nature of the magnetic Rayleigh–Taylor instability at a density interface that is permeated by an oblique homogeneous magnetic field in an incompressible limit. Methods. Using the system of linearised ideal incompressible magnetohydrodynamics equations, we derive the dispersion relation for perturbations of the contact discontinuity by imposing the necessary continuity conditions at the interface. The imaginary part of the frequency describes the growth rate of waves due to instability. The growth rate of waves is studied by numerically solving the dispersion relation. Results. The critical wavenumber at which waves become unstable, which is present for a parallel magnetic field, disappears because the magnetic field is inclined. Instead, waves are shown to be unstable for all wavenumbers. Theoretical results are applied to diagnose the structure of the magnetic field in prominence threads. When we apply our theoretical results to observed waves in prominence plumes, we obtain a wide range of field inclination angles, from 0.5° up to 30°. These results highlight the diagnostic possibilities that our study offers.

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