Modular evolution of glutathione peroxidase genes in association with different biochemical properties of their encoded proteins in invertebrate animals

<p>Abstract</p> <p>Background</p> <p>Phospholipid hydroperoxide glutathione peroxidases (PHGPx), the most abundant isoforms of GPx families, interfere directly with hydroperoxidation of lipids. Biochemical properties of these proteins vary along with their donor organisms, which has complicated the phylogenetic classification of diverse PHGPx-like proteins. Despite efforts for comprehensive analyses, the evolutionary aspects of GPx genes in invertebrates remain largely unknown.</p> <p>Results</p> <p>We isolated GPx homologs via <it>in silico </it>screening of genomic and/or expressed sequence tag databases of eukaryotic organisms including protostomian species. Genes showing strong similarity to the mammalian PHGPx genes were commonly found in all genomes examined. GPx3- and GPx7-like genes were additionally detected from nematodes and platyhelminths, respectively. The overall distribution of the PHGPx-like proteins with different biochemical properties was biased across taxa; selenium- and glutathione (GSH)-dependent proteins were exclusively detected in platyhelminth and deuterostomian species, whereas selenium-independent and thioredoxin (Trx)-dependent enzymes were isolated in the other taxa. In comparison of genomic organization, the GSH-dependent PHGPx genes showed a conserved architectural pattern, while their Trx-dependent counterparts displayed complex exon-intron structures. A codon for the resolving Cys engaged in reductant binding was found to be substituted in a series of genes. Selection pressure to maintain the selenocysteine codon in GSH-dependent genes also appeared to be relaxed during their evolution. With the dichotomized fashion in genomic organizations, a highly polytomic topology of their phylogenetic trees implied that the GPx genes have multiple evolutionary intermediate forms.</p> <p>Conclusion</p> <p>Comparative analysis of invertebrate GPx genes provides informative evidence to support the modular pathways of GPx evolution, which have been accompanied with sporadic expansion/deletion and exon-intron remodeling. The differentiated enzymatic properties might be acquired by the evolutionary relaxation of selection pressure and/or biochemical adaptation to the acting environments. Our present study would be beneficial to get detailed insights into the complex GPx evolution, and to understand the molecular basis of the specialized physiological implications of this antioxidant system in their respective donor organisms.</p

The Correlation between Climate Change and Corporate Performance

38-43The purpose of the study is to verify the correlation of the climate change risk focusing on the influence of carbon emission on the corporate performance and discriminative response of corporate contingent upon the publishment of Sustainability Report. The results of this study show that there is a negative (-) relationship between Carbon emission intensity and corporate performance. And the negative influence of carbon emission intensity on corporate performance was found to be smaller for companies that published sustainability reports than for those that did not. This study provided empirical evidences on why corporate’s active reactive activities according to the climate change is essential for sustainable development

Dissolved Organic Matter Fractions and Their Removal in Full-Scale Drinking Water Treatment Process

Objectives The objective of this study is to investigate characteristics about removal of dissolved organic matter (DOM) and its fraction for improving operation efficiency in an advanced water treatment plant. Methods The monitoring of water quality was conducted at five processes such as raw water, pre-oxidation, after sedimentation, post-ozonation, after biological activated carbon (BAC) from July 2020 to August 2021 in advanced water treatment process (AWTP) supplying 180,000m3/day. The concentration of DOC (dissolved organic carbon) and number of algae were monitored and LC-OCD was used to fractionate DOC to four species, biopolymer (BP), humic substance (HS), building blocks (BB), and low molecular weights (LMWs). Results and Discussion The characteristics of raw water showed that the concentration of DOC and the number of algae increased with an increase in water temperature. The portion of BP and HS significantly increased at low and high water temperature, respectively, while BB and LMWs maintained the similar portion. The removal efficiency of DOC in the AWTP was achieved at 59% with each species of BP, HS, BB, and LMWs obtaining removal efficiency of 87%, 65%, 26%, and 52%, respectively. Coagulation/sedimentation/filtration showed removal efficiency of 84%, 56%, 20%, and 18% for BP, HS, BB, and LMWs, respectively, corresponding to their molecular weight. The effect of post-ozonation would be negligible except for BP. In BAC, removal efficiency of 49% and 12% were obtained for LMWs and BB (low molecular weight, respectively. As a result, the BP portion significantly decreased due to high removal efficiency, while BB portion was increased in the final treated water compared to raw water. Conclusion Most of DOM was removed in coagulation/sedimentation/filtration and BAC, whereas oxidation process such as pre-chlorination, pre-ozonation and post-oxidation did not have an effect on DOM removal. In coagulation/sedimentation/filtration, 84% and 54% of the BP and HS were removed, while BAC removed 49% and 12% of LMWs and BB, respectively. It has been recommended to improve the removal efficiency of BB, which obtained the lowest removal efficiency in AWTP, and to enhance the removal efficiency of LMWs in BAC to inhibit microbial regrowth in the distribution system

PwRn1, a novel Ty3/gypsy-like retrotransposon of Paragonimus westermani: molecular characters and its differentially preserved mobile potential according to host chromosomal polyploidy

<p>Abstract</p> <p>Background</p> <p>Retrotransposons have been known to involve in the remodeling and evolution of host genome. These reverse transcribing elements, which show a complex evolutionary pathway with diverse intermediate forms, have been comprehensively analyzed from a wide range of host genomes, while the information remains limited to only a few species in the phylum Platyhelminthes.</p> <p>Results</p> <p>A LTR retrotransposon and its homologs with a strong phylogenetic affinity toward <it>CsRn1 </it>of <it>Clonorchis sinensis </it>were isolated from a trematode parasite <it>Paragonimus westermani </it>via a degenerate PCR method and from an insect species <it>Anopheles gambiae </it>by <it>in silico </it>analysis of the whole mosquito genome, respectively. These elements, designated <it>PwRn1 </it>and <it>AgCR-1 </it>– <it>AgCR-14 </it>conserved unique features including a t-RNA^Trpprimer binding site and the unusual CHCC signature of Gag proteins. Their flanking LTRs displayed >97% nucleotide identities and thus, these elements were likely to have expanded recently in the trematode and insect genomes. They evolved heterogeneous expression strategies: a single fused ORF, two separate ORFs with an identical reading frame and two ORFs overlapped by -1 frameshifting. Phylogenetic analyses suggested that the elements with the separate ORFs had evolved from an ancestral form(s) with the overlapped ORFs. The mobile potential of <it>PwRn1 </it>was likely to be maintained differentially in association with the karyotype of host genomes, as was examined by the presence/absence of intergenomic polymorphism and mRNA transcripts.</p> <p>Conclusion</p> <p>Our results on the structural diversity of <it>CsRn1</it>-like elements can provide a molecular tool to dissect a more detailed evolutionary episode of LTR retrotransposons. The <it>PwRn1</it>-associated genomic polymorphism, which is substantial in diploids, will also be informative in addressing genomic diversification following inter-/intra-specific hybridization in <it>P. westermani </it>populations.</p

The Correlation between Climate Change and Corporate Performance

The purpose of the study is to verify the correlation of the climate change risk focusing on the influence of carbon emission on the corporate performance and discriminative response of corporate contingent upon the publishment of Sustainability Report. The results of this study show that there is a negative (-) relationship between Carbon emission intensity and corporate performance. And the negative influence of carbon emission intensity on corporate performance was found to be smaller for companies that published sustainability reports than for those that did not. This study provided empirical evidences on why corporate’s active reactive activities according to the climate change is essential for sustainable developmen

A DNA barcode library of the beetle reference collection (Insecta: Coleoptera) in the National Science Museum, Korea

AbstractColeoptera is a group of insects that are most diverse among insect resources. Although used as indicator species and applied in developing new drugs, it is difficult to identify them quickly. Since the development of a method using mitochondrial DNA information for identification, studies have been conducted in Korea to swiftly and accurately identify species. The National Science Museum of Korea (NSMK) has been collecting and morphologically identifying domestic reference insects since 2013, and building a database of DNA barcodes with digital images. The NSMK completed construction of a database of digital images and DNA barcodes of 60 beetle species in the Korean National Research Information System. A total of 179 specimens and 60 species were used for the analysis, and the averages of intraspecific and interspecific variations were 0.70±0.45% and 26.34±6.01%, respectively, with variation rates ranging from 0% to 1.45% and 9.83% to 56.23%, respectively

Emergency Damage Restoration Experiences of 25MW Heavy-Duty Gas Turbine: Bearing Retrofit Design and Test Run

Case StudyCase Study 6: A 25MW gas turbine had been damaged during operation. Particularly, its tilting pad journal bearings and shaft journals had suffered complete wiping‐out and deep crack damages, respectively. For an emergency restoration, both cracked journals had been machined out as much as 2% per the specified design diameter, and a series of design, analysis and manufacturing of the retrofit journal bearings had been carried out to have practically identical overall design characteristics to the OEM bearings. To verify operational reliability, the restored GT rotor had been test‐run at KIMM's high‐speed balancing facility. Since the test results had been favorable, the rotor had been put into an onsite operation, immediately. The restored GT system has been continuously running a stable commercial operation for more than 41 months up until now. This presentation introduces design analysis of the retrofit bearings, test run result of the restored GT rotor‐bearing system, and the lessons learned

Novel PSEN1 G209A mutation in early-onset Alzheimer dementia supported by structural prediction

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.Abstract Background Three main genes are described as causative genes for early-onset Alzheimer dementia (EOAD): APP, PSEN1 and PSEN2. We describe a woman with EOAD had a novel PSEN1 mutation. Case report A 54-year-old right-handed woman presented 12-year history of progressive memory decline. She was clinically diagnosed as familial Alzheimer's disease due to a PSEN1 mutation. One of two daughters also has the same mutation, G209A in the TM-IV of PS1 protein. Her mother had unspecified dementia that began at the age of 40s. PolyPhen2 and SIFT prediction suggested that G209A might be a damaging variant with high scores. 3D modeling revealed that G209A exchange could result significant changes in the PS1 protein. Conclusion We report a case of EOAD having probable novel PSEN1 (G209A) mutation verified with structural prediction