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.Research progress in the relationship between vitamin and inflammatory bowel disease
Xiaofei PAN ; Shengmei SHI ; e Xiao' ZHANG ; Liting HAO ; Cunying MENG
Clinical Medicine of China 2017;33(10):957-960
Objective Inflammatory bowel disease(IBD)is an unexplained chronic and recurrent inflammatory disease of the intestine,including ulcerative colitis(UC)and Crohn′s disease(CD).At present, the etiology and pathogenesis of IBD are still not clear,and it is believed to be related to the environment, inheritance,infection,immunity and other factors.With the increase of people′s living standard and the economic and social development,the incidence of IBD in China is a rising trend year by year,the impact of diet on the incidence of IBD and the influence of nutritional support on the prognosis of IBD have attracted more and more attention.Vitamin is one of the seven nutrients and is an indispensable part of the health of the body.In recent years,some vitamins have been proved to be related with the occurrence and development of IBD.
10.Improvement of the Synthesis Technology of 7-methoxy-4-(2-methyl-4-quinazolinyl)-3,4-dihydroquinoxalin-2 (1H)-ketone
Jiang SHI ; DILIXIATI·Baikeli ; Chen ZHANG ; Xiao E ; Dongfeng YIN ; Xiaofeng WANG
China Pharmacy 2018;29(6):746-749
OBJECTIVE:To improve the synthesis technology of 7-methoxy-4-(2-methyl-4-quinazolinyl)-3,4-dihydroquinoxalin-2 (1H)-ketone. METHODS:Using 2-methyl-4(3H)-quinazolone as starting material,the synthesis technology of 7-methoxy-4-(2-methyl-4-quinazolinyl)-3,4-dihydroquinoxalin-2(1H)-ketone was improved by clorination, nucleophilic substitution, diarylamine alkylation and nitro reductive cyclization. The yield of it was investigated. RESULTS:The structure of 7-methoxy-4-(2-methyl-4-quinazolinyl)-3,4-dihydroquinoxalin-2(1H)-ketone had been verified by 1H-NMR and ESI-MS. The yield was 43.5%and improved by 23.3% compared to 20.2% before improvement. CONCLUSIONS:Improved technology is simpler and milder, which is suitable for the batch preparation of laboratory study.