Effects of Lignocellulose-derived Inhibitors on Growth and Succinic Acid Accumulation by Corynebacterium glutamicum

Hong-Tao Xu,Chen Wang,Zhi-Hui Zhou,Zhong-Jun Chen,Heng Cai 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.4

Succinic acid production by genetically engineered C. glutamicum from lignocellulosic biomass requires the hydrolysis of carbohydrate polymers into fermentable syrup. A variety of toxic compounds are produced such as aldehydes and organic acids, while the hydrolysis of hemicellulose with dilute acid. In this study, we have investigated the toxicity of representative aldehydes (furfural, 5-hydroxymethylfurfural, syringaldehyde, and vanillin) and organic acids (ferulic, 4-hydroxybenzic, vanillic, protocatechuic acid) on growth and succinic acid accumulation of C. glutamicum NC-1. In the presence of various inhibitors of growth experiment, furfural, 5- hydroxymethylfurfural appeared less toxic to growth of C. glutamicum NC-1, syringaldehyde almost completely inhibitor growth of C. glutamicum NC-1, vanillin has inhibited the growth of 67%, of organic acids, only ferulic appeared toxic to growth of C. glutamicum NC-1. Of succinic acid accumulation experiment under oxygen deprivation, all the organic acids compounds showed little inhibition on the glocuse consumption and succinic acid accumulation of C. glutamicum NC-1, but furfural, 5- hydroxymethylfurfural and vanillic have decreased the production of succinic acid. In addition, the actual inhibitor mixtures from the acid hydrolysate of corn cobs have reduced the accumulation of succinic acid. Across further research showed, a reason of succinic acid yield decrease was the malic enzyme activity was inhibited.

Lasiokaurin derivatives: synthesis, antimicrobial and antitumor biological evaluation, and apoptosis-inducing effects

Da-Hong Li,Ping Hu,Sheng-tao Xu,Chun-yan Fang,Shuang Tang,Xin-yu Wang,Xing-yan Sun,He Lian,Ying Xu,Xiao-ke Gu,Jin-yi Xu 대한약학회 2017 Archives of Pharmacal Research Vol.40 No.7

Herein, a series of lasiokaurin derivatives were designed and synthesized. All the derivatives together with lasiokaurin and oridonin were tested for their antimicrobial and antiproliferative activity. Compound 16 showed the most promising antimicrobial activity with MICs of 2.0 and 1.0 lg/mL against Gram-Positive bacteria S. aureus and B. subtilis, respectively. All the synthetic lasiokaurin derivatives showed better antiproliferative activity than parent compound lasiokaurin 1. Compound 10 exhibited the strongest cytotoxicity with IC50 values of 0.47 and 0.20 lM against MGC-803 and CaEs-17 cells, accordingly. Moreover, it was shown to have potent antitumor activity in vivo in a murine model of MGC-803 gastric cancer. Preliminary SARs were also concluded based on obtained data. The apoptosis-inducing effects of 10 were further investigated using CaEs-17 cells. The results showed that lasiokaurin derivative 10 could induce apoptosis via mitochondria related pathway and arrest CaEs-17 cell cycle at S phase. Compound 10 could also affect apoptosisrelated proteins that was up-regulation of CDK2 and downregulation of ATM and cyclin A1.

Bioactive enmein-type 6,7-seco-ent-kaurane diterpenoids: natural products, synthetic derivatives and apoptosis related mechanism

Haonan Li,Baojia Sun,Mingying Wang,Xu Hu,Xiang Gao,Sheng-tao Xu,Yongnan Xu,Jin-yi Xu,Hui-Ming Hua,Da-Hong Li 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.11

Diterpenoids are important and widely distributed natural compounds with various biological effects, including antitumor, anti-inflammatory and so on. Great efforts have been put in phytochemistry research on diterpenoids. A number of structural modified derivatives and pharmacophore incorporated hybrids were also designed and synthesized with promising therapeutic effects. Among the hopefuls, enmein-type 6,7-seco-ent-kaurane diterpenoids with unique ring system and stereogenic centers exhibit attractive activities. Based on their lead-like properties, enmein-type diterpenoids are suitable for further medicinal study. The derivatives were biologically evaluated and showed promising activities, which warranted in-depth research for further understanding. In this review, the natural bioactive enmein-type diterpenoids and the synthetic derivatives were comprehensively summarized.

Construction of Modified Bacillus thuringiensis cry1Ac Genes for Transgenic Crop Through Multi Site-directed Mutagenesis

Xu, Hong Guang,Roh, Jong-Yul,Wang, Yong,Choi, Jae-Young,Shim, Hee-Jin,Liu, Qin,Tao, Xueying,Woo, Soo-Dong,Jin, Byung-Rae,Je, Yeon-Ho Korean Society of Sericultural Science 2009 International Journal of Industrial Entomology Vol.19 No.1

The newly cloned Bacillus thuringiensis cry1-5 gene showed high activity to both Plutella xylostella and Spodoptera exigua, while cry1Ac only showed high activity against P. xylostella but low to S. exigua. Through the alignment of amino acid sequences between Cry1Ac and Cry1-5, we found 12 different residues in domain I (6 residues) and domain II (6 residues). In this study, the modified cry1Ac gene, which is constructed according to a crop-preferring codon usage, was used as a template to construct mutant B. thuringiensis cry1Ac genes based on cry1-5 gene through multi site-directed mutagenesis. Total 63 various mutant cry genes were obtained at 12 positions randomly. Among them, ten mutant cry genes, whose domain I was totally converted and domain II was randomly, were selected to express in baculovirus expression system as a polyhedrin fusion form. The recombinant proteins were 95 kDa in size and were stably activated as 65 kDa by trypsin. The expressed mutant Cry proteins were applied to bioassays against P. xylostella and S. exigua. All mutants showed high insecticidal activity both to P. xylostella and S. exigua similar to cry1-5. These results suggest that these mutant cry genes might be expected of desirable cry genes for introduction to transgenic crops.

CHRNA5 rs16969968 Polymorphism Association with Risk of Lung Cancer - Evidence from 17,962 Lung Cancer Cases and 77,216 Control Subjects

Xu, Zhi-Wei,Wang, Guan-Nan,Dong, Zhou-Zhou,Li, Tao-Hong,Cao, Chao,Jin, Yu-Hong Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.15

Background: Genetic studies have shown a possible relationship between the rs16969968 polymorphism in CHRNA5 and the risk of lung cancer. However, the results have been conflicting. Thus we rigorously conducted a meta-analysis to clarify any association. Materials and Methods: A total of 10 case-control studies involving 17,962 lung cancer cases and 77,216 control subjects were analysed. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to measure the strength of the association. Results: We found the CHRNA5 rs16969968 polymorphism to be associated with the risk of lung cancer (AA vs GG: OR=1.60, 95%CI=1.51-1.71). On stratified analysis by smoking status, a statistically significant increased risk was observed in the smoking group (AA vs GG: OR=1.80, 95%CI=1.61-2.01). However, this polymorphism was not associated with lung cancer risk in Asians (AA vs GG: OR=0.95, 95%CI=0.35-2.59), whereas it was linked to increased risk of lung cancer among Caucasians (AA vs GG: OR=1.65, 95%CI=1.55-1.76). Conclusions: Our meta-analysis provided statistical evidence for a strong association between rs16969968 polymorphism and the risk of lung cancer, especially in smokers and Caucasians. Application of this relationship may contribute to identification of individuals at high risk of lung cancer and indicate a chemoprevention target.

Transcriptome sequencing and analysis of sweet osmanthus (Osmanthus fragrans Lour.)

Hong Na Mu,Liang Gui Wang,Huo Gen Li,Xiu Lian Yang,Tao Ze Sun,Chen Xu 한국유전학회 2014 Genes & Genomics Vol.36 No.6

Osmanthus fragrans is a woody, evergreenspecies of shrubs and small trees that is extensively plantedin sub-tropical and temperate climates as an ornamentalplant in gardens and for its health benefits. The flower colorranges from ivory to orange to pink among different varietiesand even color difference during the whole blossom inthe sweet osmanthus. Sweet osmanthus is widely cultivatedthroughout China and other countries due to its prominentfragrance, colorful flowers, and medicinal properties. However, the scanty genomic resources in the Olea familyhave greatly hindered further exploration of its geneticmechanism on these economically important traits. In thisstudy, transcriptome sequencing of O. fragrans was performedusing the Illumina HighSeqTM2000 sequencingplatform. Next generation sequencing (NGS) of the transcriptomeof O. fragrans produced 31.7G of clean bases(211,266,818 clean reads) that were assembled into256,774 transcripts and 117,595 unigenes. Of them, 197and 237 candidate genes involved in fragrance and pigmentbiosynthesis respectively were identified based on functionannotation. Meanwhile, 1 unnamed protein and 468 functionalunknown genes were also identified. Furthermore,mRNA sequencing expression profiling of O. fragranswere compared to previous genes’. In summary, thiscomprehensive transcriptome dataset allows the identificationof genes associated with several major metabolicpathways and provides a useful public information platformfor further functional genomic studiesin O. fragransLour.

Two-phase flow pattern online monitoring system based on convolutional neural network and transfer learning

Xu Hong,Tang Tao 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.12

Two-phase flow may almost exist in every branch of the energy industry. For the corresponding engineering design, it is very essential and crucial to monitor flow patterns and their transitions accurately. With the high-speed development and success of deep learning based on convolutional neural network (CNN), the study of flow pattern identification recently almost focused on this methodology. Additionally, the photographing technique has attractive implementation features as well, since it is normally considerably less expensive than other techniques. The development of such a two-phase flow pattern online monitoring system is the objective of this work, which seldom studied before. The ongoing preliminary engineering design (including hardware and software) of the system are introduced. The flow pattern identification method based on CNNs and transfer learning was discussed in detail. Several potential CNN candidates such as ALexNet, VggNet16 and ResNets were introduced and compared with each other based on a flow pattern dataset. According to the results, ResNet50 is the most promising CNN network for the system owing to its high precision, fast classification and strong robustness. This work can be a reference for the online monitoring system design in the energy system.

Application of artificial neural network for the critical flow prediction of discharge nozzle

Hong Xu,Tao Tang,Baorui Zhang,Yuechan Liu 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.3

System thermal-hydraulic (STH) code is adopted for nuclear safety analysis. The critical flow model(CFM) is significant for the accuracy of STH simulation. To overcome the defects of current CFMs (lowprecision or long calculation time), a CFM based on a genetic neural network (GNN) has been developedin this work. To build a powerful model, besides the critical mass flux, the critical pressure and criticalquality were also considered in this model, which was seldom considered before. Comparing with thetraditional homogeneous equilibrium model (HEM) and the Moody model, the GNN model can predictthe critical mass flux with a higher accuracy (approximately 80% of results are within the ±20% errorlimit); comparing with the Leung model and the Shannak model for critical pressure prediction, the GNNmodel achieved the best results (more than 80% prediction results within the ±20% error limit). For thecritical quality, similar precision is achieved. The GNN-based CFM in this work is meaningful for the STHcode CFM development

The Establishment of a Fast and Safe Orthotopic Colon Cancer Model Using a Tissue Adhesive Technique

Hong-Tao Hu,Zhe Wang,김명지,Jiang Lushang,Shi-Jun Xu,정재윤,이은지,박정훈,Nader Bakheet,윤성환,김건영,송호영,장수환 대한암학회 2021 Cancer Research and Treatment Vol.53 No.3

Purpose We aimed to develop a novel method for orthotopic colon cancer model, using tissue adhesive in place of conventional surgical method.Materials and Methods RFP HCT 116 cell line were used to establish the colon cancer model. Fresh tumor tissue harvested from a subcutaneous injection was grafted into twenty nude mice, divided into group A (suture method) and group B (tissue adhesive method). For the group A, we fixed the tissue on the serosa layer of proximal colon by 8-0 surgical suture. For the group B, tissue adhesive (10 μL) was used to fix the tumor. The mortality, tumor implantation success, tumor metastasis, primary tumor size, and operation time were compared between the two groups. Dissected tumor tissue was analyzed for the histology and immunohistochemistry. Also, we performed tumor marker analysis.Results We observed 30% increase in graft success and 20% decrease in mortality, by using tissue adhesive method, respectively. The median colon tumor size was significantly increased by 4 mm and operation time was shortened by 6.5 minutes. The H&E showed similar tumor structure between the two groups. The immunohistochemistry staining for cancer antigen 19-9, carcinoembryonic antigen, cytokeratin 20, and Ki-67 showed comparable intensities in both groups. Real-time quantitative reverse transcription analysis showed eight out of nine tumor markers are unchanged in the tissue adhesive group. Western blot indicated the tissue adhesive group expressed less p-JNK (apototic marker) and more p-MEK/p-p38 (proliferation marker) levels.Conclusion We concluded the tissue adhesive method is a quick and safe way to generate orthotopic, colon cancer model.

Construction of Modified Bacillus thuringiensis cry1Ac Genes for Transgenic Crop Through Multi Site-directed Mutagenesis

Hong Guang Xu,Jong Yul Roh,Yong Wang,Jae Young Choi,Hee Jin Shim,Qin Liu,Xue Ying Tao,Soo Dong Woo,Byung Rae Jin,Yeon Ho Je 한국잠사학회 2009 International Journal of Industrial Entomology Vol.19 No.1

The newly cloned Bacillus thuringiensis cry1-5 gene showed high activity to both Plutella xylostella and Spodoptera exigua, while cry1Ac only showed high activity against P. xylostella but low to S. exigua. Through the alignment of amino acid sequences between Cry1Ac and Cry1-5, we found 12 different residues in domain I (6 residues) and domain II (6 residues). In this study, the modified cry1Ac gene, which is constructed according to a crop-preferring codon usage, was used as a template to construct mutant B. thuringiensis cry1Ac genes based on cry1-5 gene through multi site-directed mutagenesis. Total 63 various mutant cry genes were obtained at 12 positions randomly. Among them, ten mutant cry genes, whose domain I was totally converted and domain II was randomly, were selected to express in baculovirus expression system as a polyhedrin fusion form. The recombinant proteins were 95 kDa in size and were stably activated as 65 kDa by trypsin. The expressed mutant Cry proteins were applied to bioassays against P. xylostella and S. exigua. All mutants showed high insecticidal activity both to P. xylostella and S. exigua similar to cry1-5. These results suggest that these mutant cry genes might be expected of desirable cry genes for introduction to transgenic crops.