1.Preparation of metal chelate affinity chromatographic medium and its application in the purification of 6 x histidine-tagged protein.
Shu-Juan LI ; Yong-Liang SUN ; Dao-Dao HU ; Chao CHEN ; Ya-Li CUI
Chinese Journal of Biotechnology 2007;23(5):941-946
Using Sepharose CL-6B as support, 3-Chloro-1, 2-epoxypropane as activated agent, carboxymethylated aspartate (CM-Asp) as chelating ligand, A chelate affinity chromatographic medium based on Co2+, named Co-CM-Asp-Sepharose, was prepared and used to purify 6 x His-tagged fusion proteins. The amount of Co-CM-Asp-Sepharose reacted with 200 microL of lysate, the incubation time, wash condition and the imidazole concentration in the elution buffer were optimized. The purification results using Co-CM-Asp-Sepharose and Ni-NTA-Agarose (product of Qiagen) were compared. The CD155D1 fusion protein was also purified from 5mL of lysate and the amount of protein was determined by Bradford method. The results show that 60 microL of Co-CM-Asp-Sepharose (50% suspension) was suitable for the protein purification from 200 microL of lysate, the optimal incubation time of medium and lysate was 30 min, the optimal imidazole concentration in the eluting buffer was 200 mmol/L, and 200 microg of fusion protein was obtained. In a big scale experiment, 4.6 mg of fusion protein was obtained from 5 mL of lysate using 1.5 mL of Co-CM-Asp-Sepharose (50% suspension). Compared with Ni-NTA-Agarose, the Co-CM-Asp-Sepharose medium exhibits higher selectivity and the protein possesses higher purity.
Aspartic Acid
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chemistry
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Chelating Agents
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chemistry
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Chromatography, Affinity
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methods
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Epoxy Compounds
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chemistry
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Histidine
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biosynthesis
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chemistry
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genetics
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Polymers
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chemistry
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Recombinant Fusion Proteins
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isolation & purification
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Sepharose
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chemistry
2.Molecular imaging of thrombus with microbubbles targeted to alphavbeta3-integrin using an agarose flow chamber model.
Guang-quan HU ; Jian LIU ; Li YANG ; Yi YAN ; Jue-fei WU ; Jia-jia XIE ; Jing-jing CAI ; Li-jing JI ; Jian-ping BIN
Journal of Southern Medical University 2010;30(3):478-481
OBJECTIVETo assess the binding ability of microbubbles targeted to alphavbeta3-integrin (MBp) for thrombus-targeted contrast-enhanced ultrasound.
METHODSTargeted microbubbles were prepared by conjugating the monoclonal antibody against alphavbeta3-integrin to lipid shell of the microbubble via the avidin-biotin bridges. Equivalent isotype control microbubbles (MB) or targeted ultrasound microbubbles (MBp) were randomly added into the flow chamber. After a 30-min incubation with the thrombus fixed in an agarose flow chamber model, the thrombus was washed with a continuous flow of PBS solution (15 cm/s) for 2, 4, 6, 8 and 10 min, followed by thrombus imaging using contrast-enhanced ultrasound and measurement of the video intensity (VI) values of the images.
RESULTSThe VI of the thrombus in MBp group was reduced by 28%-66%, while that in control MB group was decreased by 87%-94%, and the VI values of the thrombus group were significantly greater in former group at each of the time points (P<0.05).
CONCLUSIONMBP has good targeting ability to the thrombus with resistance to the shear stress after adhesion to the thrombus. In vitro evaluation of the thrombus-binding capability of the targeted microbubble (MBp) by simulating the shear stress in vivo can be helpful for predicting the in vivo effects of ultrasonic molecular imaging using MBp.
Antibodies, Monoclonal ; chemistry ; immunology ; Contrast Media ; chemistry ; Humans ; Integrin alphaVbeta3 ; immunology ; metabolism ; Microbubbles ; Sepharose ; Thrombosis ; diagnostic imaging ; Ultrasonography
3.Study on preparation of a wound healing agent: fibronectin.
Guowei REN ; Xuefang HUANG ; Libing DAI ; Huizhen YE ; Peihong LIANG
Journal of Biomedical Engineering 2003;20(3):531-533
In search of the optimal preparation method for large-scale purification of human plasma fibronectin, we adopted affinity chromatography with gelatin and the Sepharose 4B activated with cyanogen bromide to purify fibronectin from type "C" plasma of healthy males, and scanned the best method under the conditions of different amount of plasma loading and different residence time in column. In a given column volume of gelatin, the absorbent was related with the plasma residence time in column and the total amount of plasma loaded. As a result, the optimal loading amount of plasma is 150 ml, and the residence time is 20 minutes. The preparation method, herein, has been proved to require small amount of plasma and yield large amount of fibronectin.
Chromatography, Affinity
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methods
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Cyanogen Bromide
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chemistry
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Fibronectins
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blood
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isolation & purification
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Gelatin
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Humans
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Male
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Sepharose
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chemistry
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Wound Healing
4.An enzymatic method for the detection of human serum albumin.
Masood Ul Hassan JAVED ; Saima N WAQAR
Experimental & Molecular Medicine 2001;33(2):103-105
Albumin is the most abundant protein in human serum. A dye-binding method is commonly used in clinical laboratories for its estimation using different types of dyes. However, all these dye methods were interfered by a variety of compounds. Here we present a method for the detection of albumin in human serum and other biological fluids. The principle is based on the fact that lactate dehydrogenase isoenzyme-5 (LDH-5) binds specifically to Dextran-Blue (DB). Albumin inhibits the binding of LDH-5 with DB. Absence of LDH activity in DB fraction after gel filtration indicates the presence of albumin in sample and vice versa.
Chemistry, Clinical/*methods
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Chromatography, Gel
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Human
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Isoenzymes/metabolism
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Lactate Dehydrogenase/metabolism
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Protein Binding
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Sepharose/chemistry
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Serum Albumin/*analysis
5.Disease-specific Proteins from Rheumatoid Arthritis Patients.
Choong Won KIM ; Eun Hye CHO ; Yun Jong LEE ; Yoon Hee KIM ; Young Sool HAH ; Deok Ryong KIM
Journal of Korean Medical Science 2006;21(3):478-484
Rheumatoid arthritis (RA) is a chronic inflammatiory disease that mainly destroys cartilages or bones at the joints. This inflammatory disorder is initiated by self-attack using own immune system, but the detail of pathological mechanism is unclear. Features of autoantigens leading to autoimmune disease are also under veil although several candidates including type II collagen have been suggested to play a role in pathogenesis. In this report, we tried to identify proteins responding to antibodies purified from RA patients and screen proteins up-regulated or down-regulated in RA using proteomic approach. Fibronectin, semaphorin 7A precursor, growth factor binding protein 7 (GRB7), and immunoglobulin mu chain were specifically associated with antibodies isolated from RA synovial fluids. In addition, some metabolic proteins such as adipocyte fatty acid binding protein, galectin-1 and apolipoprotein A1 precursor were overexpressed in RA synovium. Also, expression of peroxiredoxin 2 was up-regulated in RA. On the contrary, expression of vimentin was severely suppressed in RA synoviocytes. Such findings might give some insights into understanding of pathological mechanism in RA.
Synovial Fluid/metabolism
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Sepharose/chemistry
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Proteomics/methods
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Middle Aged
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Male
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*Inflammation
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Humans
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*Gene Expression Regulation
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Female
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Collagen Type II/biosynthesis
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Autoantigens/metabolism
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Arthritis, Rheumatoid/*metabolism
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Aged
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Adult
6.A novel approach for identifying the heme-binding proteins from mouse tissues.
Xiaolei LI ; Xiaoshan WANG ; Kang ZHAO ; Zhengfeng ZHOU ; Caifeng ZHAO ; Ren YAN ; Liang LIN ; Tingting LEI ; Jianning YIN ; Rong WANG ; Zhongsheng SUN ; Zuyuan XU ; Jingyue BAO ; Xiuqing ZHANG ; Xiaoli FENG ; Siqi LIU
Genomics, Proteomics & Bioinformatics 2003;1(1):78-86
Heme is a key cofactor in aerobic life, both in eukaryotes and prokaryotes. Because of the high reactivity of ferrous protoporphyrin IX, the reactions of heme in cells are often carried out through heme-protein complexes. Traditionally studies of heme-binding proteins have been approached on a case by case basis, thus there is a limited global view of the distribution of heme-binding proteins in different cells or tissues. The procedure described here is aimed at profiling heme-binding proteins in mouse tissues sequentially by 1) purification of heme-binding proteins by heme-agarose, an affinity chromatographic resin; 2) isolation of heme-binding proteins by SDS-PAGE or two-dimensional electrophoresis; 3) identification of heme-binding proteins by mass spectrometry. In five mouse tissues, over 600 protein spots were visualized on 2-DE gel stained by Commassie blue and 154 proteins were identified by MALDI-TOF, in which most proteins belong to heme related. This methodology makes it possible to globally characterize the heme-binding proteins in a biological system.
Animals
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Carrier Proteins
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biosynthesis
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genetics
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Electrophoresis, Gel, Two-Dimensional
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Electrophoresis, Polyacrylamide Gel
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Heme
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chemistry
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Hemeproteins
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biosynthesis
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genetics
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Mass Spectrometry
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Mice
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Mice, Inbred ICR
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Protein Binding
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Proteins
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chemistry
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Proteome
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Proteomics
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methods
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Sepharose
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chemistry
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Tissue Distribution
7.Modification of seaweed polysaccharide-agarose and its application as skin dressing (III)--skin regeneration with agarose grafting hyaluronic acid sponge.
Jianyan HUANG ; Lingmin ZHANG ; Bin CHU ; Peng CHEN ; Shunqing TANG
Journal of Biomedical Engineering 2011;28(1):95-98
In this paper, a kind of skin dressing, agarose- grafting- hyaluronic acid (Ag-g-HA) sponge was applied to test the modified agarose based scaffold for skin regeneration. The bFGF loading agarose-grafting hyaluronan scaffold had homogenous porosities, and the loaded bFGF was bioactive in 2 weeks. The Ag-g-HA sponge was applied into skin of mice, and it was found that the dressing promoted skin regeneration and no infection and leakage in lesion site took place. H&E staining results showed that the repaired skin was similar to autologous skin. These demonstrate that Ag-g-HA sponge has a promise in skin regeneration.
Animals
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Bandages
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Female
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Fibroblast Growth Factor 2
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physiology
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Hyaluronic Acid
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therapeutic use
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Mice
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Mice, Inbred C57BL
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Polysaccharides
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isolation & purification
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therapeutic use
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Random Allocation
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Seaweed
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chemistry
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Sepharose
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isolation & purification
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therapeutic use
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Surgical Sponges
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Wound Healing
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drug effects
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Wounds and Injuries
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therapy