Molecular and Biochemical Characterization of a Novel Intracellular Low-Temperature-Active Xylanase

( Jun Pei Zhou,),( Yan Yan Dong ),( Xiang Hua Tang ),( Jun Jun Li ),( Bo Xu ),( Qian Wu ),( Ya Jie Gao ),( Lu Pan ),( Zun Xi Huang ) 한국미생물 · 생명공학회 2012 Journal of microbiology and biotechnology Vol.22 No.4

A 990 bp full-length gene (xynAHJ2) encoding a 329- residue polypeptide (XynAHJ2) with a calculated mass of 38.4 kDa was cloned from Bacillus sp. HJ2 harbored in a saline soil. XynAHJ2 showed no signal peptide, distinct amino acid stretches of glycoside hydrolase (GH) family 10 intracellular endoxylanases, and the highest amino acid sequence identity of 65.3% with the identified GH 10 intracellular mesophilic endoxylanase iM-KRICT PX1-Ps from Paenibacillus sp. HPL-001 (ACJ06666). The recombinant enzyme (rXynAHJ2) was expressed in Escherichia coli and displayed the typical characteristics of low-temperatureactive enzyme (exhibiting optimum activity at 35 o C, 62% at 20 o C, and 38% at 10 o C; thermolability at ≥45 o C). Compared with the reported GH 10 low-temperature-active endoxylanases, which are all extracellular, rXynAHJ2 showed low amino acid sequence identities (<45%), low homology (different phylogenetic cluster), and difference of structure (decreased amount of total accessible surface area and exposed nonpolar accessible surface area). Compared with the reported GH 10 intracellular endoxylanases, which are all mesophilic and thermophilic, rXynAHJ2 has decreased numbers of arginine residues and salt bridges, and showed resistance to Ni 2+ , Ca 2+ , or EDTA at 10 mM final concentration. The above mechanism of structural adaptation for low-temperature activity of intracellular endoxylanase rXynAHJ2 is different from that of GH 10 extracellular low-temperature-active endoxylanases. This is the first report of the molecular and biochemical characterizations of a novel intracellular low-temperatureactive xylanase.

Production and Characterization of Ethanol- and Protease-Tolerant and Xylooligosaccharides-Producing Endoxylanase from Humicola sp Ly01

( Jun Pei Zhou ),( Qian Wu ),( Rui Zhang ),( Yu Ying Yang ),( Xiang Hua Tang ),( Jun Jun Li ),( Jun Mei Ding ),( Yan Yan Dong ),( Zun Xi Huang ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.6

This paper reports the production and characterization of crude xylanase from the newly isolated Humicola sp. Ly01. The highest (41.8 U/ml) production of the crude xylanase was obtained under the optimized conditions (w/v): 0.5% wheat bran, 0.2% KH2PO4, and 0.5% peptone; initial pH 7.0; incubation time 72 h; 30℃; and 150 rpm. A considerable amount of the crude xylanase was induced using hulless barley bran or soybean meal as the carbon source, but a small amount of the enzyme was produced when supplementary urea was used as the nitrogen source to wheat bran. The crude xylanase showed apparent optimal cellulase-free xylanase activity at 60℃ and pH 6.0, more than 71.8% of the maximum xylanase activity in 3.0-30.0% (v/v) ethanol and more than 82.3% of the initial xylanase activity after incubation in 3.0-30.0% (v/v) ethanol at 30℃ for 2 h. The crude xylanase was moderately resistant to both acid and neutral protease digestion, and released 7.9 and 10.9 μmol/ml reducing sugar from xylan in the simulated gastric and intestinal fluids, respectively. The xylooligosaccharides were the main products of the hydrolysis of xylan by the crude xylanase. These properties suggested the potential of the crude enzyme for being applied in the animal feed industry, xylooligosaccharides production, and high-alcohol conditions such as ethanol production and brewing.

Comparative Study on Transcatheter Arterial Chemoembolization, Portal Vein Embolization and High Intensity Focused Ultrasound Sequential Therapy for Patients

Cui, Lin,Liu, Xing-Xiang,Jiang, Yong,Wu, Xing-Jun,Liu, Jian-Jun,Zhou, Xiang-Rong,He, Xue-Jun,Huang, Xin-En Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

Objective: To investigate the safety and efficacy of transcatheter arterial chemoembolization (TACE), combined with portal vein embolization (PVE), and high intensity focused ultrasound (HIFU) sequential therapy in treating patients with hepatocellular carcinoma (HCC). Methods: Patients with inoperative HCC were treated by two methods: in the study group with TACE first, then PVE a week later, and then TACE+PVE every two months as a cycle, after 2~3 cycles finally HIFU was given; in the control group only TACE+PVE was given. Response (CR+PR), and disease control rate (CR+PR+SD), side effects, overall survival and time to progress were calculated. Results: Main side effects of both groups were nausea and vomiting. No treatment related death occurred. In the study group, 32 patients received TACE for overall 67 times, PVE 64 times, and HIFU 99 times; on average 2.1, 2 and 3.1 times for each patient, respectively. In the control group, 36 patients were given TACE 78 times and PVE 74 times, averaging 2.2 and 2.1 times per patient. Effective rate: 25.0% in study group and 8.3% in control group (p>0.05). Disease control rates were 71.9% and 44.4%, respectively (p<0.05). In patients with portal vein tumor thrombus, the rate reduced over 1/2 after treatment was 69.2%(9/13) in the study and 21.4%(3/14) in the control group (p<0.05). Rate of AFP reversion or decrease over 1/2 was 66.7%(16/24) in study and 37%(10/27) (p<0.05) in control group. Median survival time: 16 months in study and 10 months in control group. PFS was 7months in study and 3 months in control group. Log-rank test suggested that statistically significant difference exists between two groups (p=0.024). 1-, 2- and 3-year survival rates were 56.3%, 18.8% and 9.3% in study, while 30.6%, 5.6% and 0 in control group, respectively, with statistically significant difference between two groups (by Log-rank, p = 0.014). Conclusions: The treatment of TACE+PVE+HIFU sequential therapy for HCC increases response rate, prolong survival, and could thus be a safe and effective treatment for advanced cases.

Molecular and Biochemical Characterization of a Novel Xylanase from Massilia sp. RBM26 Isolated from the Feces of Rhinopithecus bieti

( Bo Xu ),( Li Ming Dai ),( Jun Jun Li ),( Meng Deng ),( Hua Biao Miao ),( Jun Pei Zhou ),( Yue Lin Mu ),( Qian Wu ),( Xiang Hua Tang ),( Yun Juan Yang ),( Jun Mei Ding ),( Nan Yu Han ),( Zun Xi Huang 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.1

Xylanases sourced from different bacteria have significantly different enzymatic properties. Therefore, studying xylanases from different bacteria is important to their applications in different fields. A potential xylanase degradation gene in Massilia was recently discovered through genomic sequencing. However, its xylanase activity remains unexplored. This paper is the first to report a xylanase (XynRBM26) belonging to the glycosyl hydrolase family (GH10) from the genus Massilia. The gene encodes a 383-residue polypeptide (XynRBM26) with the highest identity of 62% with the endoxylanase from uncultured bacterium BLR13. The XynRBM26 expressed in Escherichia coli BL21 is a monomer with a molecular mass of 45.0 kDa. According to enzymatic characteristic analysis, pH 5.5 is the most appropriate for XynRBM26, which could maintain more than 90% activity between pH 5.0 and 8.0. Moreover, XynRBM26 is stable at 37°C and could maintain at least 96% activity after being placed at 37°C for 1 h. This paper is the first to report that GH10 xylanase in an animal gastrointestinal tract (GIT) has salt tolerance, which could maintain 86% activity in 5 M NaCl. Under the optimum conditions, Km, Vmax, and kcat of XynRBM26 to beechwood xylan are 9.49 mg/ml, 65.79 μmol/min/mg, and 47.34 /sec, respectively. Considering that XynRBM26 comes from an animal GIT, this xylanase has potential application in feedstuff. Moreover, XynRBM26 is applicable to high-salt food and seafood processing, as well as other high-salt environmental biotechnological fields, because of its high catalytic activity in high-concentration NaCl.

Molecular Biology and Omics : Cloning and Characterization of a Novel α-Amylase from a Fecal Microbial Metagenome

( Bo Xu ),( Fu Ya Yang ),( Cai Yun Xiong ),( Jun Jun Li ),( Xiang Hua Tang ),( Jun Pei Zhou ),( Zhen Rong Xie ),( Jun Mei Ding ),( Yun Juan Yang ),( Zun Xi Huang ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.4

To isolate novel and useful microbial enzymes from uncultured gastrointestinal microorganisms, a fecal microbial metagenomic library of the pygmy loris was constructed. The library was screened for amylolytic activity, and 8 of 50,000 recombinant clones showed amylolytic activity. Subcloning and sequence analysis of a positive clone led to the identification a novel gene (amyPL) coding for α-amylase. AmyPL was expressed in Escherichia coli BL21 (DE3) and the purified AmyPL was enzymatically characterized. This study is the first to report the molecular and biochemical characterization of a novel α-amylase from a gastrointestinal metagenomic library.

New power equalization modulation strategy for CHB seven‑level inverters

Jun Gu,Run-Zhe Cai,Xiang-Yu Zhou,Chao Ding,Wei-Jian Wang 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.7

For cascaded H-bridge (CHB) multilevel converters, the traditional in-phase disposition (IPD) modulation strategy has excellent harmonic elimination characteristics, but it leads to a single state of the switching tubes and unbalanced output power of each unit. In this paper, a new power equalization modulation strategy and its optimization are proposed, which solves the problem of power equalization, while taking into account the harmonic elimination performance of the output voltage and power equalization time. The new power equalization modulation strategy makes the carrier rotate in different carrier layers in a new interval, and the voltage of each unit is readjusted using the redundant switching states. Thus, the output power equalization can be achieved in a shorter time. While maintaining the output characteristics of the existing modulation strategy, the new modulation strategy reduces the power equalization time and preserves the harmonic elimination characteristics of IPD. In addition, the optimized modulation strategy reduces the number of carriers, lowering the difficulty of digital control. Finally, simulation and experimental results are used to verify the correctness and feasibility of the new power equalization modulation strategy and its optimization.

Hepatic Sinusoidal Obstruction Syndrome Caused by Herbal Medicine: CT and MRI Features

Hua Zhou,Yi-Xiang J. Wang,Hai-yan Lou,Xiao-jun Xu,Min-ming Zhang 대한영상의학회 2014 Korean Journal of Radiology Vol.15 No.2

Objective: To describe the CT and MRI features of hepatic sinusoidal obstruction syndrome (HSOS) caused by herbal medicine Gynura segetum. Materials and Methods: The CT and MRI features of 16 consecutive Gynura segetum induced HSOS cases (12 men, 4 women) were analyzed. Eight patients had CT; three patients had MRI, and the remaining five patients had both CT and MRI examinations. Based on their clinical presentations and outcomes, the patients were classified into three categories:mild, moderate, and severe. The severity of the disease was also evaluated radiologically based on the abnormal hepatic patchy enhancement in post-contrast CT or MRI images. Results: Ascites, patchy liver enhancement, and main right hepatic vein narrowing or occlusion were present in all 16 cases. Hepatomegaly and gallbladder wall thickening were present in 14 cases (87.5%, 14/16). Periportal high intensity on T2-weighted images was present in 6 cases (75%, 6/8). Normal liver parenchymal enhancement surrounding the mainhepatic vein forming a clover-like sign was observed in 4 cases (25%, 4/16). The extent of patchy liver enhancement was statistically associated with clinical severity classification (kappa = 0.565). Conclusion: Ascites, patchy liver enhancement, and the main hepatic veins narrowing were the most frequent signs of herbal medicine induced HSOS. The grade of abnormal patchy liver enhancement was associated with the clinical severity.

Meta Analysis of Association of the IL-17F rs763780T>C Gene Polymorphism with Cancer Risk

Chen, Xiang-Jun,Zhou, Tao-You,Chen, Min,Pu, Dan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

Purpose: To investigate the association of IL-17F rs763780T>C with cancer risk. Materials and Methods: We searched the Cochrane Central Library, PubMed, MEDLINE, EMBASE, CNKI (China National Knowledge Infrastructure) and WangFang databases until May 2014 for a meta-analysis conducted using RevMan 5.2 software. Results: A total of ten papers were included into this meta analysis, involving 3, 336 cases and 4, 217 healthy people. There were no significant differences on association of IL-17F rs763780T>C polymorphism with cancer risk except in the CC vs TT genetic model. Although the the risk in the gastric cancer group is higher than that in control group, there were no significant differences on the association of IL-17F rs763780T>C polymorphism with other cancers. Conclusions: Our meta analysis reveal the IL-17A rs763780T>C gene polymorphism is involved in risk of gastric cancer but not other tumor types.

Application of Highly Charged PAC and Polyamine admixture in Neutral Papermaking

YANYONG-XIANG,CHEN FU-SHAN,WANGLI-JUN,ZHOU LIN-JIE 한국펄프·종이공학회 2006 한국펄프종이학회 기타 간행물 Vol.- No.-

Studied that the relationship between the charge density of PAC and its alkalinity, as well as the influences of PAC in paper sizing. Study results showed that PAC with higher charge density brought higher sizing degree when the same amount of Al₂O₃ content was dosed. However, there was no direct relationship between PAC charge density and its alkalinity, and higher PAC alkalinity can’t improve its charge density. It was also found that the admixture (PPAC) of polyamine and PAC had higher charge density than PAC. The effects of PPAC on DRS and RAKD sizing were better than PAC sizing, when dosage and other sizing condition were the same.

Association of the miRNA146a rs2910164 C>G Polymorphism with Head and Neck Cancer Risk: A Meta-analysis

Chen, Xiang-Jun,Zhou, Tao-You,Chen, Min,Li, Nian,Liu, Fang Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Objective: To investigate any association of the miRNA146a rs2910164 C>G polymorphism with head and neck cancer risk. Materials and Methods: The Medline, PubMed, PUBMED, EMBASE, Web of Science, WanFang and CNKI databases were searched and a meta-analysis was conducted using RevMan 5.2 software. Results: After searching and evaluating the literature, a total seven papers involving 2,766 patients with head and neck cancer and 6,603 healthy controls were included into this meta analysis. The results showed that there were no significant differences between patients and healthy controls overall for the miRNA rs2910164 C>G gene polymorphism (dominant model:OR=0.78, 95%CI:0.58-1.04, P=0.09; recessive model:OR=0.86, 95%CI:0.67-1.12, P=0.27;GG:CC:OR=0.75, 95%CI:0.52-1.08, P=0.12;GC:CC:OR=0.79, 95%CI:0.60-1.04, P=0.10). However, a significant association of miRNA rs2910164 C>G gene polymorphism with Chinese head and neck cancer risk was noted, limited to the dominant model (OR=0.68, 95%CI:0.50-0.95, P=0.02;GG:CC:OR=0.62, 95%CI:0.42-0.92, P=0.02;GC:CC:OR=0.72, 95%CI:0.520.99, P=0.04). Conclusions: miRNA146a rs2910164 C>G polymorphism is not associated with head and neck cancer risk in general, but tehre may be link in Chinese.