A Highly Active Alpha Amylase from Bacillus Licheniformis: Directed Evolution, Enzyme Characterization and Structural Analysis

( Yi Han Liu ),( Shu Ai Fan ),( Xiao Guang Liu ),( Zhi Meng Zhang ),( Jian Ling Wang ),( Zheng Xiang Wang ),( Fu Ping Lu ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.7

The stability of Bacillus licheniformis alpha-amylase (BLA) under acid condition was enhanced through direct evolution using the error-prone polymerase chain reaction. One beneficial mutation site, H281I, was obtained in BLA. The specific activity of H281I was 161/352 U/mg, which was 62.6/27.5% higher than that of the wild-type (WT) (99/276 U/mg) at pH 4.5/6.5 and 95°C. The pH optimum for H281I was decreased about 1 unit, whereas no significant changes of optimum temperature and thermostability were observed compared with the wild type (WT). The kcat/Km value of H281I was 1.7-/1.4-fold higher at pH 4.5/6.5, respectively, than that of WT. The structure model analysis indicated that the H281I mutation altered the predicted interaction between the amino acid residues at 281 and 273, thus creating a conducive local environment for substrate binding, as reflected by its decreased Km, and consequently increased the specific activity.

Identification and characterization of atypical porcine pestivirus genomes in newborn piglets with congenital tremor in China

Han-Qin Shen,Xiangcong Liu,Pengfei Zhang,Lei Wang,Yan-ling Liu,Le-yi Zhang,Peng-shuai Liang,Chang-xu Song 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.3

Recently, a novel atypical porcine pestivirus (APPV) in pig was reported. In this study, two APPV strains, APPV-China/GZ01/2016 (GZ01) and APPV-China/GD-SD/2016 (GD-SD), were identified in two newborn piglet herds with congenital tremor from China. The open reading frame of the two strains shared an 83.5% nucleotide identity. Phylogenetically, the APPV strains were placed into two groups: GZ01 belonged to group I and GD-SD belonged to group II. A high viral load was detected in the cerebellum (quantification cycles < 26). Further studies should be carried out to thoroughly elucidate the development of congenital tremors caused by APPV.

Weight Gain in Pregnancy, Maternal Age and Gestational Age in Relation to Fetal Macrosomia

( Yi Li ),( Qi-fei Liu ),( Dan Zhang ),( Ying Shen ),( Kui Ye ),( Han-lin Lai ),( Hai-qing Wang ),( Chuan-lai Hu ),( Qi-hong Zhao ),( Li Li ) 한국임상영양학회 2015 Clinical Nutrition Research Vol.4 No.2

To investigate the possible risk factors related to macrosomia. Pregnant women and their newborns (n = 1041) were recruited from a cohort study in Maternal and Child Care Center of Hefei from January 2011 to July 2012. Questionnaires were applied to collect the demographic data besides the medical records. Detailed health records of the entire pregnancy were obtained using retrospective study. Meanwhile the data of neonatal outcomes was prospectively tracked. Associations between exposure risk factors and macrosomia were analyzed using Pearson’s chi squared test. Logistic regression models were used to assess the independent association between these potential predictors and macrosomia. The incidence of macrosomia of this cohort was 11.24% of which male: female = 2.55:1. Male incidence (8.07%) of macrosomia was higher than female (3.17%), p < 0.001. Body mass index (BMI) before pregnancy (pre-BMI), maternal height, parity were not independently associated with macrosomia; multiple logistic regression analysis indicated that macrosomia was mainly independently associated with weight gain in pregnancy (OR=1.14,95% CI [1.10-1.19]), maternal age (OR = 1.09,95% CI [1.03-1.15]) and gestational age (OR = 1.62,95% CI [1.31-1.99]), respectively. Our findings indicate that weight gain in pregnancy, maternal age and gestational age should be considered as independent risk factors for macrosomia.

The role of extracellular vesicles in osteoarthritis treatment via microenvironment regulation

Han Yin,Muzhe Li,Guangzhao Tian,Yang Ma,Chao Ning,Zineng Yan,Jiang Wu,Qian Ge,Xiang Sui,Shu-Yun Liu,Jinxuan Zheng,Weimin Guo,Quan-Yi Guo 한국생체재료학회 2022 생체재료학회지 Vol.26 No.4

Osteoarthritis (OA) is a degenerative joint disease that is common among the middle-aged and older populations, causes patients to experience recurrent pain in their joints and negatively affects their quality of life. Currently, therapeutic options for patients with OA consist of medications to alleviate pain and treat the symptoms; however, due to typically poor outcomes, patients with advanced OA are unlikely to avoid joint replacement. In recent years, several studies have linked disrupted homeostasis of the joint cavity microenvironment to the development of OA. Recently, extracellular vesicles (EVs) have received increasing attention in the field of OA. EVs are natural nano-microcarrier materials with unique biological activity that are produced by cells through paracrine action. They are composed of lipid bilayers that contain physiologically active molecules, such as nucleic acids and proteins. Moreover, EVs may participate in local and distal intercellular and intracellular communication. EVs have also recently been shown to influence OA development by regulating biochemical factors in the OA microenvironmental. In this article, we first describe the microenvironment of OA. Then, we provide an overview of EVs, summarize the main types used for the treatment of OA, and describe their mechanisms. Next, we review clinical studies using EVs for OA treatment. Finally, the specific mechanism underlying the application of miRNA-enriched EVs in OA therapy is described.

Transcriptome characterization and expression analysis related to sex‐determining genes in Chilo sacchariphagus (Lepidoptera Crambidae), a key pest of sugarcane

Liu Jianbai,Wu Han,Yi Jiequn,Li Jihu,Cheng Yinjie,Cheng Yinjie,Sun Donglei,An Yuxing 한국곤충학회 2022 Entomological Research Vol.52 No.2

Chilo sacchariphagus is one of the most harmful pests of sugarcane, sorghum, corn, and other crops, in China and other countries and regions. In order to elucidate the molecular mechanisms involved in the sexually dimorphic development of C. sacchariphagus, transcriptome data of female and male adults were obtained. A total of 127,812,174 and 126,593,664 clean reads of males and females were arranged into 45,693 and 37,034 unigenes for males and females, respectively, 26,949 of which were annotated. Candidate genes involved in sexual development were identified and analysed. Statistical analysis revealed that 18,642 genes were differentially expressed in females and males, 9,307 of which were up-regulated in males and 9,335 of which were up-regulated in females. As indicated by GO classification, DEGs were mainly involved in cell part, cellular process and binding. KEGG enrichment analysis showed that 6,037 DEGs were assigned to 295 metabolic pathways. Based on annotation and transcriptome data, we identified twenty-two sex determining genes, of which Csactra2, Csacemc, Csacfru, Csacix, Csacovo, CsacdsxM,andCsacsxl showed a higher expression in males than that in females, while CsacgroX4, Csacfem, CsacgroX9, Csacmsl1, Csacmsl2, Csacmsl3, Csacotu, Csacvir, Csacrunt,andCsacdsxF were more highly expressed in female. In addition, Csactra2 and CsacgroX9 were enriched in Spliceosome, Notch signaling, and Wnt signaling pathways, respectively. And the pathways are crucial in regulating insect growth, differentiation and development. This transcriptome study provides rich and significant information regarding the genes involved in sex differentiation and determination, which would improve our understanding of the molecular mechanisms related to sex determination and be helpful for providing the basis for a wide spectrum of strategies to benefit pest control and prevention, and agriculture and public health

Kinetics and computational docking studies on the inhibition of tyrosinase induced by oxymatrine.

Liu, Xiao-Xia,Sun, Shi-Qing,Wang, Yu-Jie,Xu, Wei,Wang, Yi-Fang,Park, Daeui,Zhou, Hai-Meng,Han, Hong-Yan Humana Press 2013 Applied biochemistry and biotechnology Vol.169 No.1

<P>A combination of enzymatic inhibition kinetics and computational prediction was employed to search for an effective inhibitor of tyrosinase. We found that oxymatrine significantly inhibited tyrosinase, and that this reaction was not accompanied by detectable conformational changes. Kinetic analysis showed that oxymatrine reversibly inhibited tyrosinase in a mixed-type manner. Measurements of intrinsic and ANS-binding fluorescences showed that oxymatrine did not induce any conspicuous changes in the tertiary structure. We also conducted a docking simulation between tyrosinase and oxymatrine using two docking programs, Dock6.3 and AutoDock4.2 (binding energy was -118.81 kcal/mol for Dock6 and -8.04 kcal/mol for AutoDock4). The results also suggested that oxymatrine interacts mostly with the residues of CYS83 and HIS263 in the active site of tyrosinase. This strategy of predicting tyrosinase inhibition by simulation of docking coupling with kinetics may prove useful in screening for potential tyrosinase inhibitors. Knowledge of tyrosinase inhibition can provide medical, cosmetic, and agricultural applications. Our study suggests that oxymatrine is an important agent for various applications related to pigment formation.</P>

Study of a Magnetic Switch for the SG-III Energy Module

Liu Gang,Lin Fuchang,Liu Yi,Li Hua,Lee Li,Zeng Han 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.61

The SG-III energy module, which supplies pumping energy for Xenon (Xe) flashlamps, is one of the most important modules in large laser facilities. A two-electrode spark gap switch is used as the main discharge switch and is triggered by a Marx generator. The peak value of the output impulse generated by the Marx generator is about 180 kV, and its rise time is about 10 ns. In order to prevent the key elements (e.g., Xe flashlamps) from being damaged by the trigger impulse, a magnetic switch is used to isolate the high-voltage impulse. The design, working principle and performance of a magnetic switch based on Fe-based nanocrystals are presented in this paper. Compared with the magnetic switch employed in magnetic pulse compressors (MPCs), the magnetic switch in SGIII works under a single nanosecond impulse. It corresponds to the initial magnetization curve of the B-H curve. The parameters of the Fe-based nanocrystals are obtained by experiments. The unsaturated inductance, saturated inductance and saturation time are the key parameters of the magnetic switch in SG-III and are considered in the design. Finally, the experimental results for the magnetic switch in SG-III are presented.

Transcriptome characterization and profiling related to detoxification enzyme genes in Chilo sacchariphagus (Lepidoptera Crambidae)

Liu Jianbai,Yi Jiequn,Wu Han,Lu Yinglin,Mao Yongkai,Lin Mingjiang,Li Jihu,An Yuxing 한국곤충학회 2022 Entomological Research Vol.52 No.9

Chilo sacchariphagus Bojeris is one of the most dangerous pests of sugarcane. The larvae damage the seedlings and stems of sugarcane and also harm sorghum, corn and other crops, which causes great economic losses to the sugar industry every year. Transcriptome sequencing and expression profile analysis of cytochrome P450 monooxygenase (CYP), carboxylesterase and glutathione S-transferase (GST) were carried out, which could provide a basis for drug resistance monitoring and drug resistance management of the pest. Unigenes of C. sacchariphagus were obtained by using the Illumina HiSeqTM 4,000 platform as 150 bp paired-end reads. A total of 173,013 unigenes were obtained after data assembly and redundancy removal. 28,330 unigenes were annotated based on multiple public databases, and the number of unigenes annotated by NR database was the largest. According to the transcriptome analysis, 214 candidate detoxification enzyme genes were identified, including 44 GSTs,138CYPs, and 32 CarEs. Phylogenetic analysis showed that the CYPs were mainly clustered in CYP4, CYP6, CYP9 and CYP12 subfamilies; CarEs mainly include antennal CarEs, venom CarEs and CarEs NOTUM; while the GSTs cluster mainly contains subfamilies such as delta, omega, epsilon, theta, zeta and sigma. In this study, transcriptome information of C. sacchariphagus was obtained, and genes related to detoxification were identified, which could provide data and a basis for the further study of detoxification and host plant adaptation mechanism of C. sacchariphagus.

Piperacillin-Tazobactam-Induced Linear IgA Bullous Dermatosis Supported by a T-Cell Activation Assay

( Yi-hsin Ho ),( Yun-wen Chiu ),( Han-nan Liu ) 대한피부과학회 2018 Annals of Dermatology Vol.30 No.5

Linear immunoglobulin (Ig) A bullous dermatosis (LABD) is a rare subepidermal autoimmune blistering disease characterized by linear IgA deposits at the basement membrane zone visualized with direct immunofluorescence (DIF). Most cases of LABD are idiopathic, but some are drug-induced with vancomycin being the most common causative agent. We herein report a patient presenting with blisters and erosive lesions, primarily in the intertriginous and flexor areas, consistent with a diagnosis of piperacillin-tazobactam-induced LABD based on the patient’s clinical course and histopathology, DIF, and in vitro T-cell activation assay (TAA) findings. Only one case of piperacillin-tazobactam-induced LABD has been previously reported. In addition to its rarity, our case was also unique in that the skin lesions occurred in the intertriginous and flexor areas, uncommon locations for typical adult patients with LABD, and TAA strongly suggested an association with the causative drug. (Ann Dermatol 30(5) 588∼591, 2018)

mRNA Expression and Clinical Significance of ERCC1, BRCA1, RRM1, TYMS and TUBB3 in Postoperative Patients with Non-Small Cell Lung Cancer

Han, Yi,Wang, Xiao-Bin,Xiao, Ning,Liu, Zhi-Dong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.5

Background: To explore mRNA expression and clinical significance of ERCC1, BRCA1, RRM1, TYMS and TUBB3 genes in tumor tissue of postoperative patients with non-small cell lung cancer (NSCLC). Materials and Methods: Sixty NSCLC patients undergoing radical operation in our hospital from Nov., 2011 to Jun., 2012 were selected. Plasmid standards of ERCC1, BRCA1, RRM1, TYMS and TUBB3 were established and standard curves were prepared by SYBR fluorescent real-time quantitative PCR analysis. Samples from tumor centers were taken to detect mRNA expression of ERCC1, BRCA1, RRM1, TYMS and TUBB3 genes in cancerous tissue during operation. The total mRNA expression quantities were compared according to different clinical characteristics. Results: The total expression quantities of 5 genotypes from high to low were ERCC1>RRM1>TUBB3>TYMS>BRCA1 in turn. By pairwise comparisons, other differences showed statistical significance (p<0.05 or p<0.01) except for TYMS and TUBB3 (p>0.05); the low expression rates from high to low were ERCC1>TYMS>TUBB3>TUBB3>RRM1>BRCA1 in turn. The expression quantities of BRCA1, RRM1 and TYMS in males, smokers and patients without adenocarcinoma were all significantly higher than that in females, non-smokers and patients with adenocarcinoma, and significant differences were present (p<0.05 or p<0.01). In terms of pathological staging, the expression quantities of BRCA1, RRM1 and TYMS in phases IIa~IIb and IIIa~IIIb had a tendency to be greater than in phases I and IV. Conclusions: Resistance to chemotherapy and sensitivity to targeted therapy differ among patients with NSCLC. Differences in gene expression in different individuals were also revealed. Only according to personalized detection results can individualized therapeutic regimens be worked out, which is a new direction for oncotherapy.