2.Cloning and expressing of cellulase gene (cbh2) from thermophilic fungi Chaetomium thermophilum CT2.
Shou-An LIU ; Duo-Chuan LI ; Shi-Jin E ; Yan ZHANG
Chinese Journal of Biotechnology 2005;21(6):892-899
Chaetomium thermophilum CT2 can produce extracellular cellulase with industrial value. We designed two degenerate primers to amplify catalytic domain sequence of cellobiohydrolase II ( CBH II). Full length of cDNA was obtained by rapid amplification of cDNA ends technologies. DNA sequencing revealed that cbh2 has an open reading frame of 1428bp, which encodes a putative polypeptide of 476 amino acids. The deduced amino acid sequence shows that the predicted molecular mass is 53 kD and the cbh2 consists of a fungal-type carbohydrate binding domain (CBD) separated from a catalytic domain by a linker region rich in proline/serine/threonine. PCR product consisting of the entire CBH II coding region without its signal sequences was cloned into the yeast secretive plasmid pPIC9K, which was then transformed into Pichia pastoris GS115. Highly efficient production of the cellobiohydrolase II was achieved in P. pastoris under the control of the AOX1 promoter, and the expressing level was 1.2 mg/mL by small-scale culturing. The recombinant cellobiohydrolase II was purified by using ammonium sulfate fraction, DEAE-Sepharose Fast flow chromatography. A molecular mass of the purified enzyme is 67 kD determined by SDS-PAGE and this is similar to the native cellobiohydrolase II purified from C. thermophilum CT2. The recombinant enzyme exhibited optimum catalytic activity at pH 4.0 and 50 degrees C respectively. It was thermostable at 50 degrees C and retained 50% of its original activity after 30 min at 70 d degrees C . The high level of fully active recombinant cellobiohydrolase II got from P. pastoris makes this expression system attractive for fermentor and industrial applications.
Amino Acid Sequence
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Base Sequence
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Cellulose 1,4-beta-Cellobiosidase
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biosynthesis
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genetics
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Chaetomium
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enzymology
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genetics
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Cloning, Molecular
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DNA, Complementary
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genetics
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Fungal Proteins
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biosynthesis
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genetics
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Molecular Sequence Data
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Open Reading Frames
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genetics
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Pichia
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genetics
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metabolism
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Recombinant Proteins
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biosynthesis
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genetics
5.The development of a scale to measure the proactive socialization behavior and its impact on ;turnover intention of new nurses
Xu LIU ; Shuo WANG ; Guangming CHANG ; Shu′e ZHANG ; Fengzhe XIE ; Yu SHI ; Jinghui WANG ; Xinyue GUO ; Dexin MENG
Chinese Journal of Practical Nursing 2017;33(3):216-219
Objective To preliminarily develop a scale to measure the proactive socialization behavior of new nurses and test validity and reliability of the scale, to explore the impact of proactive socialization behavior on turnover intention. Methods Using a questionnaire survey method to investigate 696 new nurses who had worked within three years in nursing organization, structural equation model and hierarchical line regression methods were performed to analyze the data. Results Proactive socialization behavior scale included eight items under one dimension;the consistency coefficient of scale was 0.858;new scale had a good convergent and predictive validity;the proactive socialization behavior of new nurses was significantly negative related to turnover intention (β=-0.236,P<0.01). Conclusions The proactive socialization behavior scale has a good reliability, convergent and predictive validity. Meanwhile, new nurses with higher level of proactive socialization behavior have lower turnover intention. Because they can quickly fit the new environment, role definition and organizational culture, which in turn organization embeddedness is promoted.
7.Effect of RU486 on apoptosis and p53 expression at the boundary of fetal-maternal interface of rhesus monkey (Macaca mulatta).
Peng WEI ; E-mail: LIUYX@PANDA.IOZ.AC.CN ; Shi-Xin TAO ; Xue-Sen ZHANG ; Zhao-Yuan HU ; Liu YI-XUN
Acta Physiologica Sinica 2004;56(1):60-65
Primate placentation involves a series of cell proliferation, immigration and apoptosis which account for the progressive tissue remodelling at the implantation site. p53 is an important proto-oncogene involved in the regulation of cell-cycle and apoptosis. To study the effect of RU486 on apoptosis and expression of p53 at the fetal-maternal interface, the location of apoptotic cells and expression of p53 were examined using in situ 3'-end labeling method, immunohistochemistry and Western blot assay at the fetal-maternal interface of normal and RU486 treated rhesus monkey. Western blot analysis showed the specificity of the anti-human antibody used with the monkey tissue. In the placental villi, the apoptotic nuclei were observed mainly in the syncytiotrophoblast and part of the cytotrophoblast within the cell column; p53 protein was detected mainly in the cytotrophoblast. In the endometrium, positive signals for apoptosis and p53 were detected in some stromal cells. After two days of mifepristone treatment, the apoptotic cells increased significantly in both placental villi and endometrium. In the villi, the increased apoptotic nuclei were mainly localized to the cytotrophoblast. At the same time, p53-positive nuclei also increased in both villous cytotrophoblast cells and endometrial stromal cells, after the treatment of RU486. These results suggest that apoptosis and expression of p53 are essential in regulating trophoblastic homeostasis by controlling its proliferation in normal placenta, whereas the up-regulation of p53 protein may play an important role in apoptosis that happens at the fetal-maternal interface induced by RU486.
Abortifacient Agents, Steroidal
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pharmacology
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Animals
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Apoptosis
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drug effects
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Chorionic Villi
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pathology
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Female
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Macaca mulatta
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Mifepristone
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pharmacology
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Placentation
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drug effects
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physiology
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Pregnancy
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Tumor Suppressor Protein p53
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biosynthesis
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genetics
8.Apopotic gene Bax expression in carotid plaque.
Bao-Zhong MEN ; E-mail: MENBAOZ@MSN.COM. ; Ding-Biao ZHOU ; Huai-Yin SHI ; Xiao-Ming ZHANG
Neuroscience Bulletin 2006;22(1):58-62
The expression of BAX in carotid atherosclerosis and its regulation is far from defined. Objectives To investigate BAX expression in stable/fibrous and instable/vulnerable carotid plaque and its clinical significance. Methods Twenty-five cases of carotid plaque specimens obtained from endarterectomy were divided into two groups, stable/fibrous 14 cases, vulnerable/instable 11 cases; aortic artery and its branches from hepatic transplantation donors 6 case as control. The expression of proapoptotic BAX was detected by immunohistochemistry (IHC), in situ hybridization(ISH) and in situ TdT dUTP nick end labeling (TUNEL). Results Five cases of BAX ( + ) were detected by ICH and ISH, 4 case of TUNEL ( + ) were detected by TUNEL in stable/fibrous carotid plaque , while 10 cases were BAX ( + )by IHC(P < 0.05) , 11 cases by ISH and 9 cases by TUNEL were detected in instable/vulnerable carotid plaque ( P < 0.01 ), respectively. The intensity of BAX ( + ) cells by IHC and ISH was (8.63 +/- 2.62) and (10.32 +/- 3.12) in fibrous plaques, whereas (122 +/- 21.64) and (152 +/- 23.35) in vulnerable plaques, respectively. No expression of BAX was found in controlled group. Conclusion The higher expression of Bax in vulnerable carotid plaque may be one mechanism in molecular pathogenesis of carotid atherosclerosis which affect plaque stability and be the cause of higher incidence of stroke than fibrous carotid plaques, the regulation of BAX expression in different stage of atherosclerosis may provide targets in gene therapy for carotid atherosclerosis.
9.Lowered sarcoendoplasmic reticulum calcium uptake and diaphragmatic SERCA1 expression contribute to diaphragmatic contractile and relaxation dysfunction in septic rats.
Jian-You ZHANG ; Jin WU ; Shi-Tong LI ; Yuan GONG
Journal of Southern Medical University 2016;37(4):438-443
OBJECTIVEThe explore the mechanism responsible for diaphragmatic contractile and relaxation dysfunction in a rat model of sepsis.
METHODSThirty-six adult male Sprague-Dawley rats were randomized equally into a sham-operated group and two model groups of sepsis induced by cecal ligation and puncture (CLP) for examination at 6 and 12 h following CLP (CLP-6 h and CLP-12 h groups). The parameters of diaphragm contractile and relaxation were measured, and the calcium uptake and release rates of the diaphragmatic sarcoendoplasmic reticulum (SR) and the protein expressions of SERCA1, SERCA2 and RyR in the diaphragmatic muscles were determined.
RESULTSThe half-relaxation time of the diaphragm was extended in both the CLP-6 h and CLP-12 h groups with significantly reduced maximum tension declinerate and the peek uptake rate of SERCA (P<0.01). Diaphragmatic maximum twitch force development rate, the maximal twitch, tetanus tensions and the peek release rate of SR decreased only at 12h after CLP (P<0.01). The expression levels of SERCA1 protein decreased significantly in the diaphragmatic muscles at 12h following CLP (P<0.01) while SERCA2 expression level and SERCA activity showed no significant changes.
CONCLUSIONIn the acute stage of sepsis, both the contractile and relaxation functions of the diaphragm are impaired. Diaphragmatic relaxation dysfunction may result from reduced calcium uptake in the SR and a decreased level of SERCA1 in the diaphragmatic muscles.
Animals ; Calcium ; metabolism ; Cecum ; Diaphragm ; drug effects ; metabolism ; Endoplasmic Reticulum ; metabolism ; Ligation ; Male ; Muscle Contraction ; drug effects ; Rats ; Rats, Sprague-Dawley ; Sarcoplasmic Reticulum ; metabolism ; Sarcoplasmic Reticulum Calcium-Transporting ATPases ; metabolism ; Sepsis
10.Relationship between lipid peroxidation in blood and neurobehavioral function changes in coke oven workers.
Fang WANG ; Hong-Mei ZHANG ; Ji-Sheng NIE ; Cui-E XUE ; Ying-Tao SHI ; Qiao NIU
Chinese Journal of Industrial Hygiene and Occupational Diseases 2007;25(1):15-17
OBJECTIVETo explore the coincidence of lipid peroxidation and neurobehavioral function changes in coke oven workers.
METHODSOne hundred and thirty-four coke oven workers were divided into three groups: 35 in the oven-bottom group, 49 in the oven-side group and 50 in oven-top group. WHO recommended NCTB was performed on coke oven workers and 36 controls from material conservation department; The contents of total superoxide dismutases (T-SOD), glutathione (GSH) and malondialdehyde (MDA) in blood were determined by test kits.
RESULTSCompared with the controls, the coke oven workers showed lower levels of T-SOD and GSH (P < 0.01), significantly higher MDA levels in blood (P < 0.01), higher score on negative mood state, lower scores on positive mood state, and poorer performance in NCTB test (P < 0.05). Further analysis revealed that there was a weak positive correlation between neurobehavioral function changes and the level of lipid peroxidation with a coefficient lower than 0.25.
CONCLUSIONThe level of lipid peroxidation in coke oven workers' blood increased and coincided with neurobehavioral function impairment.
Adult ; Affect ; Anxiety ; Case-Control Studies ; Coke ; Fatigue ; Glutathione ; blood ; Humans ; Lipid Peroxidation ; Male ; Malondialdehyde ; blood ; Middle Aged ; Occupational Exposure ; adverse effects ; Superoxide Dismutase ; blood ; Young Adult