An integrated study of tyrosinase inhibition by rutin: progress using a computational simulation.

Si, Yue-Xiu,Yin, Shang-Jun,Oh, Sangho,Wang, Zhi-Jiang,Ye, Sen,Yan, Li,Yang, Jun-Mo,Park, Yong-Doo,Lee, Jinhyuk,Qian, Guo-Ying Adenine Press 2012 Journal of biomolecular structure & dynamics Vol.29 No.5

<P>Tyrosinase inhibition studies have recently gained the attention of researchers due to their potential application values. We simulated docking (binding energies for AutoDock Vina: -9.1 kcal/mol) and performed a molecular dynamics simulation to verify docking results between tyrosinase and rutin. The docking results suggest that rutin mostly interacts with histidine residues located in the active site. A 10 ns molecular dynamics simulation showed that one copper ion at the tyrosinase active site was responsible for the interaction with rutin. Kinetic analyses showed that rutin-mediated inactivation followed a first-order reaction and mono- and biphasic rate constants occurred with rutin. The inhibition was a typical competitive type with K(i) = 1.100.25 mM. Measurements of intrinsic and ANS-binding fluorescences showed that rutin showed a relatively strong binding affinity for tyrosinase and one possible binding site that could be a copper was detected accompanying with a hydrophobic exposure of tyrosinase. Cell viability testing with rutin in HaCaT keratinocytes showed that no toxic effects were produced. Taken together, rutin has the potential to be a potent anti-pigment agent. The strategy of predicting tyrosinase inhibition based on hydroxyl group number and computational simulation may prove useful for the screening of potential tyrosinase inhibitors.</P>

State detection of explosive welding structure by dual-tree complex wavelet transform based permutation entropy

Yue Si,ZhouSuo Zhang,Wei Cheng,FeiChen Yuan 국제구조공학회 2015 Steel and Composite Structures, An International J Vol.19 No.3

Recent years, explosive welding structures have been widely used in many engineering fields. The bonding state detection of explosive welding structures is significant to prevent unscheduled failures and even catastrophic accidents. However, this task still faces challenges due to the complexity of the bonding interface. In this paper, a new method called dual-tree complex wavelet transform based permutation entropy (DTCWT-PE) is proposed to detect bonding state of such structures. Benefiting from the complex analytical wavelet function, the dual-tree complex wavelet transform (DTCWT) has better shift invariance and reduced spectral aliasing compared with the traditional wavelet transform. All those characters are good for characterizing the vibration response signals. Furthermore, as a statistical measure, permutation entropy (PE) quantifies the complexity of non-stationary signals through phase space reconstruction, and thus it can be used as a viable tool to detect the change of bonding state. In order to more accurate identification and detection of bonding state, PE values derived from DTCWT coefficients are proposed to extract the state information from the vibration response signal of explosive welding structure, and then the extracted PE values serve as input vectors of support vector machine (SVM) to identify the bonding state of the structure. The experiments on bonding state detection of explosive welding pipes are presented to illustrate the feasibility and effectiveness of the proposed method.

Soluble acetylcholineesterase expression is induced by acetic acid in Drosophila melanogaster

Yue Gao,Seung Hee Han,Young Ho Kim,Si Hyeock Lee 한국응용곤충학회 2015 한국응용곤충학회 학술대회논문집 Vol.2015 No.10

Acetylcholinesterase (AChE) is a hydrolase that hydrolyzes the neurotransmitter acetylcholine. Soluble form of AChE is generated via alternative splicing and functions as a bioscavenger in Dropsophila melanogaster. In this study, effects of acetic acid on the soluble AChE expression were investigated. Treatment of acetic acid resulted in over-expression of soluble AChE in the abdomen in a dose-dependent manner. The soluble AChE was determined to be expressed in the fat body. However, no apparent change in AChE expression was observed in the head. Our finding suggests that the soluble AChE is involved in chemical defense against high concentration of acetic acid, which is a common by-product in fermenting foods. The high level of acetic acid resistance in D. melanogaster, thus, appears to have been evolved via the induction mechanism of soluble AChE expression.

The Inhibitory Effects of Cu(2+) on Exopalaemon carinicauda Arginine Kinase via Inhibition Kinetics and Molecular Dynamics Simulations.

Si, Yue-Xiu,Lee, Jinhyuk,Yin, Shang-Jun,Gu, Xiao-Xu,Park, Yong-Doo,Qian, Guo-Ying Humana Press 2015 Applied biochemistry and biotechnology Vol.176 No.4

<P>We studied the Cu2+-mediated inhibition and aggregation of Exopalaemon carinicauda arginine kinase ( ECAK). We found that Cu2+ significantly inactivated ECAK activity and double-reciprocal kinetics demonstrated that Cu2+ induced noncompetitive inhibition of arginine and ATP ( IC50=2.27 +/- 0.16 mu M; K-i for arginine=13.53 +/- 3.76; K-i for ATP=4.02 +/- 0.56). Spectrofluorometry results showed that Cu2+ induced ECAK tertiary structural changes including the exposure of hydrophobic surfaces that directly induced ECAK aggregation. The addition of osmolytes such as glycine and proline successfully blocked ECAK aggregation induced by Cu2+ and recovered ECAK activity. We built a 3D structure for ECAK using the ECAK ORF gene sequence. Molecular dynamics ( MD) and docking simulations between ECAK and Cu2+ were conducted to elucidate the binding mechanisms. The results showed that Cu2+ blocked the entrance to the ATP active site; these results are consistent with the experimental result that Cu2+ induced ECAK inactivation. Since arginine kinase ( AK) plays an important role in cellular energy metabolism in invertebrates, our study can provide new information about the effect of Cu2+ on ECAK enzymatic function and unfolding, including aggregation, and the protective effects of osmolytes on ECAK folding to better understand the role of the invertebrate ECAK metabolic enzyme in marine environments.</P>

Feeding amount and time course of plant subcellular fractions of the four sucking pest species

Si Hyeock Lee,Kyungmun Kim,Min Ju Kim,Seung Hee Han,Sang Hyeon Kim,Yue Gao 한국응용곤충학회 2018 한국응용곤충학회 학술대회논문집 Vol.2018 No.10

RNA interference (RNAi)-based strategy has been developed to control various phytophagous chewing pests. However, only a few cases of RNAi-based control success have been reported for sucking pests, suggesting that sucking pests likely ingest less amount of transgenic subcellular hairpin RNA (or dsRNA). In this study, as the basic information for the establishment of ingestion RNAi against sucking pests, feeding amount and time course of plant subcellular fractions of the four sucking pest species (Frankliniella occidentalis, Frankliniella intonsa, Tetranychus urticae and Nilaparvata lugans) were determined by quantitative PCR (qPCR). Adults of the four species were starved for 24 h and then fed with kidney bean leaf (F. occidentalis, F. intonsa, T. urticae) or rice leaf (N. lugens) for 48 h. The leaf-fed adults were collected every 6-h interval and their genomic DNA was extracted. The ingested fractions of chloroplast and nuclear were quantified using rubisco and 50s rRNA as marker genes, respectively. The ingested amount of rubisco and 50s rRNA genes in F. occidentalis, F. intonsa and T. urticae showed rapid increasing pattern after feeding and then slightly reduced over time. In contrast, N. lugens neither ingest nuclear nor showed any distinct feeding pattern of chloroplast. These results demonstrate that F. occidentalis, F. intonsa and T. urticae ingest both chloroplasts and nucleus along with cytosol as cell-feeders but N. lugens, a phloem sap feeder, does not ingest nucleus during sucking. Our findings further suggest that ingestion RNAi-based control strategy would work better for cell-feeding sucking pests compared to phloem sap-feeding sucking pests.

The antibacterial effect of xanthorrhizol as an endodontic irrigant on Enterococcus faecalis

Yue, Wonyoung,Song, Minju,Kang, Si-Mook,Kim, Baek-il,Yoon, Tai-Cheol,Kim, Euiseong The Korean Dental Association 2016 대한치과의사협회지 Vol.54 No.3

Objectives The aim of this study was to evaluate the antibacterial effect of xanthorrhizol (XTZ) on E. faecalis, compared with 2% chlorhexidine (CHX). Materials and Methods Normal physiological state (NS), starvation state (SS), and alkalization state (AS) of E. faecalis were used. A solution containing 1% XTZ in 30% ethanol, 1% dimethyl sulfoxide (DMSO), and 100 mg/ml sodium methyl cocoyl taurate was used and is referred to as Xan in this study. To determine the minimal bactericidal concentration (MBC) of Xan and CHX, $500{\mu}l$ of E. faecalis (NS and two stress states) was added to a microtube containing $500{\mu}l$ of serial 2-fold dilutions of 1% Xan and 2% CHX (1:2-1:128). The MBC of each antimicrobial was determined by the plate count method. Results The antibacterial effect of Xan was more effective on E. faecalis in AS than in the other states (NS, SS) at 0.125% Xan and 0.03325% Xan (P<0.05). In contrast, the antibacterial effect of CHX was more effective against E. faecalis in SS than the other states (NS, AS) at 0.0625% CHX (P<0.05). In SS, the antibacterial effect of CHX was more effective than that of Xan at 0.125% and 0.0625% (P<0.05). However, in AS, the antibacterial effect of Xan was more effective than that of CHX at 0.0625% and 0.03325% (P<0.05). Conclusions In endodontic retreatment cases in which it is important to effectively remove E. faecalis from the infected root canal, Xan may be more suitable when combined with NaOCl than CHX.

Genes identification and characterization of responding to three different insecticides based on transcriptome, in the diamondback moth, Plutella xylostella.

Yue Gao,KyungmunKim,Deok Ho Kwon,In Hong Jeong,J. MarshallClark,Si Hyeock Lee 한국응용곤충학회 2019 한국응용곤충학회 학술대회논문집 Vol.2019 No.04

When treating the 3rd instar larvae of the diamondback moth (DBM), Plutella xylostella, with sublethal doses (LC10) of chlorantraniliprole, indoxacarb and spinosad via leaf dipping, their tolerance to insecticides was significantly enhanced. By analyzing the differentially expressed genes (DEGs), we found a number of genes that respond commonly or specifically to the test insecticides. With the criteria of p value < 0.05 and Log2FC > 1/ < -1, a total of 476, 367 and 410 genes were determined to respond specifically to chlorantraniliprole, indoxacarb and spinosad, respectively. Gene Ontology (GO) analysis revealed that the cuticle reorganization is commonly associated in all treatments and the oxidative stress-related process is also shown in all insecticides except spinosad. Finally, the DEGs seemingly related with enhanced tolerance were chosen for further characterization, and reliability of the transcriptome data were confirmed by quantitative PCR. The functional categories of these DEGs included mostly detoxification related genes, cuticle proteins, energy metabolism and transcriptional regulation. While the commonly responding DEGs suggest that they are likely involved in defense against common intoxication process, the DEGs specifically responded to each insecticide suggests the presence of unique tolerance mechanisms to each insecticide depending on their different structure and mode of action. Their possible roles in the tolerance/resistance development were discussed.

Transcriptional profiling of diamondback moth larvae treated with sublethal doses of five different insecticides

Yue Gao,Kyungmun Kim,Deok Ho Kwon,Si Hyeock Lee 한국응용곤충학회 2017 한국응용곤충학회 학술대회논문집 Vol.2017 No.04

To identify genes that commonly respond to the treatment of different insecticides, 3rd instar larvae of the diamondback moth, Plutella xylostella, were treated with sublethal doses (<LC10) of chlorantraniliprole, cypermethrin, dinotefuran, indoxacarb and spinosad via leaf dipping. Then, transcriptomic profiles of treated larvae were compared with that of untreated control. A total of 117,181 transcripts in average with a mean length of 662 bp were generated by de novo assembly, of which 35,329 transcripts were annotated. Among them, 207, 153, 336, 360, and 262 transcripts were determined to be up-regulated whereas 117, 47, 92, 115, and 81 genes were down-regulated following treatments with chlorantraniliprole, cypermethrin, dinotefuran, indoxacarb and spinosad, respectively. Finally, with the criteria of >10 X fold change (FC) and p < 0.05 or >4 X FC, p < 0.05 and q < 0.2, the genes commonly over-transcribed in all treated insects were selected and their over-transcription levels were confirmed by quantitative PCR. These commonly responding genes included three cytochrome P450 genes (Cyp303a1, Cyp6a20 and CYP9E2), three cuticle protein genes (LM-8, LM-19 and TM-A3A), lavesin-1, acyl-CoA D11 desaturase, glucose dehydrogenase, nose resistant to fluxetine protein 6, chorion peroxidase and protein yellow. As the five test insecticides have distinct structure and mode of action, the genes identified in this study were suggested to be involved in general chemical defense at the initial stage of intoxication. Their possible roles in tolerance and resistance development were further discussed.

Transcriptome profiling of the diamondback moth treated with sublethal doses of five different insecticides and characterization of commonly responding genes

Yue Gao,Kyungmun Kim,Deok Ho Kwon,In Hong Jeong,J. Marshall Clark,Si Hyeock Lee 한국응용곤충학회 2017 한국응용곤충학회 학술대회논문집 Vol.2017 No.10

To identify genes that commonly respond to the treatment of different insecticides and are responsible for the toleranceenhancement, transcriptomic profiles of larvae treated with sublethal doses of the five insecticides were compared withthat of untreated control. A total of 117,181 transcripts with a mean length of 662 bp were generated by de novo assembly,of which 35,329 transcripts were annotated. Among them, 125, 143, 182, 215 and 149 transcripts were determined tobe up-regulated whereas 67, 45, 60, 60 and 38 genes were down-regulated following treatments with these five insecticides.The most notable examples of commonly responding over-transcribed genes were two cytochrome P450 genes and ninecuticular protein genes. In contrast, several genes composing the mitochondrial energy generation system were significantlydown-regulated in all treated larvae. Considering the distinct structure and mode of action of the five insecticides tested,the differentially expressed genes identified in this study appear to be involved in general chemical defense at the initialstage of intoxication. Their possible roles in the tolerance/resistance development were discussed.

Transcriptome profiling of the diamondback moth treated with sublethal doses of five different insecticides and characterization of commonly responding genes

Yue Gao,Kyungmun Kim,Deok Ho Kwon,In Hong Jeong,J. Marshall Clark,Si Hyeock Lee 한국농약과학회 2017 한국농약과학회 학술발표대회 논문집 Vol.2017 No.11