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1.
Kaneko H Kamiie J Kawakami H Anada T Honda Y Shiraishi N Kamakura S Terasaki T Shimauchi H Suzuki O 《Analytical biochemistry》2011,(2):276-285
The present study was designed to determine which proteins are selectively adsorbed onto two bone substitute materials, octacalcium phosphate (OCP) and hydroxyapatite (HA) crystals, from rat serum by proteome analysis. Ground crystals of synthetic OCP and commercially available sintered HA, with the same surface area, were incubated in rat serum proteins at 37 °C for 24 h. The proteins from the crystals extracted with guanidine–HCl–EDTA were listed on the basis of the results of liquid chromatography tandem mass spectrometry (LC/MS/MS). A total of 138 proteins were detected from OCP; 103 proteins were detected from HA. Forty-eight proteins were from both crystals. A quantitative analysis of the proteins detected was performed for the extracted two bone formation-related proteins apolipoprotein E (Apo E), a protein known to promote osteoblast differentiation, and complement 3 (C3). HA adsorbed C3 (3.98 ± 0.03 fmol/μg protein) more than OCP (1.81 ± 0.07 fmol/μg protein) did, while OCP adsorbed Apo E (2.42 ± 0.03 fmol/μg protein) more than HA (1.21 ± 0.01 fmol/μg protein) did even after deleting the high-abundance proteins, such as albumin. The results demonstrated that OCP exhibits a similar property but distinct capacity with HA in adsorbing bone formation-related proteins from the serum constituents. 相似文献
2.
Siqi Gao Mengmeng Zheng Yamin Lin Kecan Lin Jinshu Zeng Shusen Xie Yun Yu Juqiang Lin 《Journal of biophotonics》2020,13(8)
Combining serum albumin via adsorption‐exfoliation on hydroxyapatite particles (HAp) with surface‐enhanced Raman scattering (SERS), we developed a novel quantitative analysis of albumin method from blood serum for cancers screening applications. The quantitatively analysis obtained by our HAp method had a good linear relationship from 1 to 10 g/dL, and the lower limit of detection was less than the albumin prognostic factor for disease (3.5 g/dL). Serum albumin was adsorbed and exfoliated by HAp from serum samples of liver cancer patients, breast cancer patients and healthy volunteers and mixed with silver colloids to perform SERS spectral analysis. Based on the PLS‐SVM algorithm, the diagnostic accuracies of liver cancer patients and breast cancer patients were 100% and 96.68%, respectively. Moreover, this algorithm successfully predicted the unidentified subjects with a diagnostic accuracy of 93.75%. This exploratory work demonstrated that HAp‐adsorbed‐exfoliated serum proteins combined with SERS spectroscopy has great potential for cancer screening. 相似文献
3.
Svendsen IE Santos O Sotres J Wennerberg A Breding K Arnebrant T Lindh L 《Biofouling》2012,28(1):87-97
Ellipsometry and mechanically assisted sodium dodecyl sulphate elution was utilized to study the adsorption of human serum albumin (HSA), human immunoglobulin G (IgG), and laminin-1, as well as competitive adsorption from a mixture of these proteins on spin-coated and sintered hydroxyapatite (HA) surfaces, respectively. The HA surfaces were characterized with respect to wettability and roughness by means of water contact angles and atomic force microscopy, respectively. Both surface types were hydrophilic, and the average roughness (Sa) and surface enlargement (Sdr) were lower for the sintered compared to the spin-coated HA surfaces. The adsorbed amounts on the sintered HA increased as follows: HSA < laminin-1 < IgG < the protein mixture. For the competitive adsorption experiments, the adsorbed fractions increased accordingly: HSA < laminin-1 < IgG on both types of HA substratum. However, a higher relative amount of HSA and laminin-1 and a lower relative amount of IgG was found on the spin-coated surfaces compared to the sintered surfaces. The effects observed could be ascribed to differences in surface roughness and chemical composition between the two types of HA substratum, and could have an influence on selection of future implant surface coatings. 相似文献
4.
The Pseudomonas aeruginosa cystic fibrosis isolate CHA induces type III secretion system-dependent but ExoU-independent oncosis of neutrophils and macrophages. Time-lapse microscopy of the infection process revealed the rapid accumulation of motile bacteria around infected cells undergoing the process of oncosis, a phenomenon we termed pack swarming. Characterization of the non-chemotactic CHAcheZ mutant showed that pack swarming is a bacterial chemotactic response to infected macrophages. A non-cytotoxic mutant, lacking the type III-secreted proteins PcrV, PopB and PopD, was able to pack swarm only in the presence of the parental strain CHA or when macrophages were pretreated with the pore-forming toxin streptolysin O. Interaction of P. aeruginosa with red blood cells (RBCs) showed that the contact-dependent haemolysis provoked by CHA requires secretion via the type III system and the PcrV, PopB/PopD proteins. The pore inserted into RBC membrane was estimated from osmoprotection experiments to be between 2.8 and 3.5 nm. CHA-infected macrophages could be protected from cell lysis with PEG3350, indicating that the pore introduced into RBC and macrophage membranes is of similar size. The time course uptake of the vital fluorescent dye, Yo-Pro-1, into infected macrophages confirmed that the formation of transmembrane pores by CHA precedes cellular oncosis. Therefore, CHA-induced macrophage death results from a pore-forming activity that is dependent on the intact pcrGVHpopBD operon. 相似文献
5.
Oriented immobilization of proteins is an important step in creating protein-based functional materials. In this study, a method was developed to orient proteins on hydroxyapatite (HA) surfaces, a widely used bone implant material, to improve protein bioactivity by employing enhanced green fluorescent protein (EGFP) and β-lactamase as model proteins. These proteins have a serine or threonine at their N-terminus that was oxidized with periodate to obtain a single aldehyde group at the same location, which can be used for the site-specific immobilization of the protein. The HA surface was modified with bifunctional hydrazine bisphosphonates (HBPs) of various length and lipophilicity. The number of functional groups on the HBP-modified HA surface, determined by a 2,4,6-trinitrobenzenesulfonic acid (TNBS) assay, was found to be 2.8 × 10(-5) mol/mg of HA and unaffected by the length of HBPs. The oxidized proteins were immobilized on the HBP-modified HA surface in an oriented manner through formation of a hydrazone bond. The relative protein immobilization amounts through various HBPs were determined by fluorescence and bicinchoninic acid (BCA) assay and showed no significant effect by length and lipophilicity of HBPs. The relative amount of HBP-immobilized EGFP was found to be 10-15 fold that of adsorbed EGFP, whereas the relative amount of β-lactamase immobilized through HBPs (2, 3, 4, 6, and 7) was not significantly different than adsorbed β-lactamase. The enzymatic activity of HBP-immobilized β-lactamase was measured with cefazolin as substrate, and it was found that the catalytic efficiency of HBP-immobilized β-lactamase improved 2-5 fold over adsorbed β-lactamase. The results obtained demonstrate the feasibility of our oriented immobilization approach and showed an increased activity of the oriented proteins in comparison with adsorbed proteins on the same hydroxyapatite surface matrix. 相似文献
6.
7.
Molecular modeling reveals binding interface of γ‐tubulin with GCP4 and interactions with noscapinoids
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The initiation of microtubule assembly within cells is guided by a cone shaped multi‐protein complex, γ‐tubulin ring complex (γTuRC) containing γ‐tubulin and atleast five other γ‐tubulin‐complex proteins (GCPs), i.e., GCP2, GCP3, GCP4, GCP5, and GCP6. The rim of γTuRC is a ring of γ‐tubulin molecules that interacts, via one of its longitudinal interfaces, with GCP2, GCP3, or GCP4 and, via other interface, with α/β?tubulin dimers recruited for the microtubule lattice formation. These interactions however, are not well understood in the absence of crystal structure of functional reconstitution of γTuRC subunits. In this study, we elucidate the atomic interactions between γ‐tubulin and GCP4 through computational techniques. We simulated two complexes of γ‐tubulin‐GCP4 complex (we called dimer1 and dimer2) for 25 ns to obtain a stable complex and calculated the ensemble average of binding free energies of ?158.82 and ?170.19 kcal/mol for dimer1 and ?79.53 and ?101.50 kcal/mol for dimer2 using MM‐PBSA and MM‐GBSA methods, respectively. These highly favourable binding free energy values points to very robust interactions between GCP4 and γ‐tubulin. From the results of the free‐energy decomposition and the computational alanine scanning calculation, we identified the amino acids crucial for the interaction of γ‐tubulin with GCP4, called hotspots. Furthermore, in the endeavour to identify chemical leads that might interact at the interface of γ‐tubulin‐GCP4 complex; we found a class of compounds based on the plant alkaloid, noscapine that binds with high affinity in a cavity close to γ‐tubulin‐GCP4 interface compared with previously reported compounds. All noscapinoids displayed stable interaction throughout the simulation, however, most robust interaction was observed for bromo‐noscapine followed by noscapine and amino‐noscapine. This offers a novel chemical scaffold for γ‐tubulin binding drugs near γ‐tubulin‐GCP4 interface. Proteins 2015; 83:827–843. © 2015 Wiley Periodicals, Inc. 相似文献
8.
The chemotactic activity of C5a and C5a des Arg can be enhanced significantly by the vitamin D-binding protein (DBP), also known as Gc-globulin. DBP is a multifunctional 56-kDa plasma protein that binds and transports several diverse ligands. The objective of this study was to investigate the mechanisms by which DBP functions as a chemotactic cofactor for C5a using neutrophils and U937 cells transfected with the C5aR (U937-C5aR cells). The results demonstrate that U937-C5aR cells show C5a chemotactic enhancement only to DBP in serum, but, unlike mature neutrophils, this cell line cannot respond to DBP in plasma or to purified DBP. Analysis by SDS-PAGE and isoelectric focusing revealed no structural difference between DBP in serum compared with DBP in plasma. However, plasma supplemented with either serum, DBP-depleted serum, or activated platelet releasate provides a required factor and permits DBP to function as a chemotactic cofactor for C5a. Fractionation of activated platelet releasate revealed that the additional factor possessed the properties of thrombospondin-1 (TSP-1). Finally, purified TSP-1 alone could reproduce the effect of serum or platelet releasate, whereas Abs to TSP-1 could block these effects. These results provide clear evidence that TSP-1 is needed for DBP to function as a chemotactic cofactor for C5a. 相似文献
9.
γ‐Tubulin complex in Trypanosoma brucei: molecular composition,subunit interdependence and requirement for axonemal central pair protein assembly
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γ‐Tubulin complex constitutes a key component of the microtubule‐organizing center and nucleates microtubule assembly. This complex differs in complexity in different organisms: the budding yeast contains the γ‐tubulin small complex (γTuSC) composed of γ‐tubulin, gamma‐tubulin complex protein (GCP)2 and GCP3, whereas animals contain the γ‐tubulin ring complex (γTuRC) composed of γTuSC and three additional proteins, GCP4, GCP5 and GCP6. In Trypanosoma brucei, the composition of the γ‐tubulin complex remains elusive, and it is not known whether it also regulates assembly of the subpellicular microtubules and the spindle microtubules. Here we report that the γ‐tubulin complex in T. brucei is composed of γ‐tubulin and three GCP proteins, GCP2‐GCP4, and is primarily localized in the basal body throughout the cell cycle. Depletion of GCP2 and GCP3, but not GCP4, disrupted the axonemal central pair microtubules, but not the subpellicular microtubules and the spindle microtubules. Furthermore, we showed that the γTuSC is required for assembly of two central pair proteins and that γTuSC subunits are mutually required for stability. Together, these results identified an unusual γ‐tubulin complex in T. brucei, uncovered an essential role of γTuSC in central pair protein assembly, and demonstrated the interdependence of individual γTuSC components for maintaining a stable complex. 相似文献
10.
Wei Li Changying Guo Zehua Yu Rutao Liu 《Journal of biochemical and molecular toxicology》2016,30(11):525-532
In this paper, we use spectroscopic methods (fluorescence spectroscopy, UV absorption spectroscopy, and circular dichroism (CD) spectroscopy) to elucidate the effects of reactive oxygen species generated by γ‐irradiation on the molecular properties of human serum albumin (HSA). The results of fluorescence spectroscopy indicated that oxidation by γ‐irradiation can lead to conformational changes of HSA. Data of CD spectra suggested that with the increase of radiation dose the percentage of α‐helix in HSA has decreased. The determination of protein hydrophobicity showed that the effective hydrophobicity of HSA decreased up to 62% compared to the native HSA solution due to the exposure to the γ‐irradiation. Furthermore, small changes in the esterase‐like activity of HSA were introduced because of oxidation. The content of bityrosine increased markedly, suggesting that the oxidized HSA was aggregated. Moreover, there was no obvious change in the molecular properties of HSA with low γ‐irradiation dose. Changes happened when the irradiation dose exceeded 200 Gy. 相似文献
11.
The vitamin D-binding protein (DBP), also known as group-specific component or Gc-globulin, is a multifunctional plasma protein that can significantly enhance the leukocyte chemotactic activity to C5a and C5a des-Arg. DBP is a member of the albumin gene family and has a triple domain modular structure with extensive disulfide bonding that is characteristic of this protein family. The goal of this study was to identify a region in DBP that mediates the chemotactic cofactor function for C5a. Full-length and truncated versions of DBP (Gc-2 allele) were expressed in Escherichia coli using a glutathione S-transferase fusion protein expression system. The structure of the expressed proteins was confirmed by SDS-PAGE and immunoblotting, whereas protein function was verified by quantitating the binding of [(3)H]vitamin D. Dibutyryl cAMP-differentiated HL-60 cells were utilized to test purified natural DBP and recombinant expressed DBP (reDBP) for their ability to enhance chemotaxis and intracellular Ca(2+) flux to C5a. Natural and full-length reDBP (458 amino acid residues) as well as truncated reDBPs that contained the N-terminal domain I (domains I and II, residues 1-378; domain I, residues 1-191) significantly enhanced both cell movement and intracellular Ca(2+) concentrations in response to C5a. Progressive truncation of DBP domain I localized the chemotactic enhancing region between residues 126-175. Overlapping peptides corresponding to this region were synthesized, and results indicate that a 20-amino-acid sequence (residues 130-149, 5'-EAFRKDPKEYANQFMWEYST-3') in domain I of DBP is essential for its C5a chemotactic cofactor function. 相似文献
12.
Human blood neutrophil leukocytes were shown by the checkerboard filter assay to be capable of chemotactic migration in response to gradients of filter-bound chemotactic proteins in the absence of protein in free solution. Chemotactic proteins (casein, denatured serum albumin) and chemokinetic proteins (native serum albumin) bind substantially to substrata such as filters and glass, whereas low molecular weight chemotactic factors such as formyl-methionyl-phenylalanine bind poorly. Cells do not locomote towards the latter factors in the absence of protein but can, when migrating on substratum-bound albumin, respond chemotactically to gradients of fluid-phase formyl peptide. 相似文献
13.
Effect of propeptide amino acid substitution in γ‐carboxylation,activity and expression of recombinant human coagulation factor IX
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The production of recombinant vitamin K dependent (VKD) proteins for therapeutic purposes is an important challenge in the pharmaceutical industry. These proteins are primarily synthesized as precursor molecules and contain pre–propeptide sequences. The propeptide is connected to γ‐carboxylase enzyme through the γ‐carboxylase recognition site for the direct γ‐carboxylation of VKD proteins that has a significant impact on their biological activity. Propeptides have different attitudes toward γ‐carboxylase and certain amino acids in propeptide sequences are responsible for the differences in γ‐carboxylase affinity. By aiming to replace amino acids in hFIX propeptide domain based on the prothrombin propeptide, pMT‐hFIX‐M14 expression cassette, containing cDNA of hFIX with substituted ?14 residues (Asp to Ala) was made. After transfection of Drosophila S2 cells, expression of the active hFIX was analyzed by performing ELISA and coagulation test. A 1.4‐fold increase in the mutant recombinant hFIX expression level was observed in comparison with that of a native recombinant hFIX. The enhanced hFIX activity and specific activity of the hFIXD‐14A (2.2 and 1.6 times, respectively) were further confirmed by comparing coagulation activity levels of substituted and native hFIX. Enrichment for functional, fully γ‐carboxylated hFIX species via barium citrate adsorption demonstrated 2‐fold enhanced recovery in the S2‐expressing hFIXD‐14A relative to that expressed native hFIX. These results show that changing ?14 residues leads to a decrease in the binding affinity to substrate, increase in γ‐carboxylation and activity of recombinant hFIX. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:515–520, 2018 相似文献
14.
CD44 and annexin A2 mediate the C5a chemotactic cofactor function of the vitamin D binding protein 总被引:2,自引:0,他引:2
The vitamin D binding protein (DBP) is a plasma protein that significantly enhances the chemotactic activity of C5a and C5a(desArg) (cochemotactic activity). The objective of this study was to investigate how DBP mediates this process using neutrophils and U937 cells transfected with the C5a receptor (U937-C5aR cells) and comparing chemotaxis to C-activated serum (DBP dependent) vs purified C5a (DBP independent). Binding to the cell surface is essential for this protein to function as a chemotactic cofactor, and DBP binds to a chondroitin sulfate proteoglycan (CSPG) on neutrophil plasma membrane preparations. To determine whether a CSPG also functions to mediate cochemotactic activity, U937-C5aR cells were grown in chlorate to inhibit CSPG sulfation or treated with chondroitinase AC. Either treatment significantly inhibited chemotaxis only to C-activated serum. CD44 is a major cell surface CSPG on leukocytes, and functions to facilitate chemotaxis. Treatment of cells with anti-CD44 blocks chemotaxis of neutrophils and U937-C5aR cells to C-activated serum but not purified C5a. DBP binds to CD44 on the cell surface as evidenced by coimmunoprecipitation, confocal microscopy, and cell binding studies. Annexin A2 associates with CD44 in lipid rafts; therefore, its potential role in mediating cochemotactic activity was investigated. Results demonstrate that anti-A2 inhibits neutrophil and U937-C5aR chemotaxis specifically to C-activated serum, blocks DBP binding to cells, and colocalizes with anti-DBP on the cell surface. These results provide clear evidence that CD44 and annexin A2 mediate the C5a chemotactic cofactor function of DBP. 相似文献
15.
Anaїs Bouissou Christel Vérollet Hélène de Forges Laurence Haren Yohanns Bellaїche Franck Perez Andreas Merdes Brigitte Raynaud‐Messina 《The EMBO journal》2014,33(2):114-128
γ‐Tubulin is critical for microtubule (MT) assembly and organization. In metazoa, this protein acts in multiprotein complexes called γ‐Tubulin Ring Complexes (γ‐TuRCs). While the subunits that constitute γ‐Tubulin Small Complexes (γ‐TuSCs), the core of the MT nucleation machinery, are essential, mutation of γ‐TuRC‐specific proteins in Drosophila causes sterility and morphological abnormalities via hitherto unidentified mechanisms. Here, we demonstrate a role of γ‐TuRCs in controlling spindle orientation independent of MT nucleation activity, both in cultured cells and in vivo, and examine a potential function for γ‐TuRCs on astral MTs. γ‐TuRCs locate along the length of astral MTs, and depletion of γ‐TuRC‐specific proteins increases MT dynamics and causes the plus‐end tracking protein EB1 to redistribute along MTs. Moreover, suppression of MT dynamics through drug treatment or EB1 down‐regulation rescues spindle orientation defects induced by γ‐TuRC depletion. Therefore, we propose a role for γ‐TuRCs in regulating spindle positioning by controlling the stability of astral MTs. 相似文献
16.
Gonzalo Montoya Rodrigo Correa Jesús Arenas Lía Hoz Enrique Romo Rita Arroyo Margarita Zeichner‐David Higinio Arzate 《Journal of peptide science》2019,25(10)
A cementum protein 1‐derived peptide (CEMP1‐p1) consisting of 20 amino acids from the CEMP1's N‐terminus region: MGTSSTDSQQAGHRRCSTSN, and its role on the mineralization process in a cell‐free system, was characterized. CEMP1‐p1's physicochemical properties, crystal formation, and hydroxyapatite (HA) nucleation assays were performed. Crystals induced by CEMP1‐p1 were analyzed by scanning electron microscopy, Fourier‐transform infrared spectroscopy‐attenuated total reflectance (FTIR‐ATR), X‐ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and atomic force microscopy. The results indicate that CEMP1‐p1 lacks secondary structure, forms nanospheres that organize into three‐dimensional structures, possesses affinity to HA, and induces its nucleation. CEMP1‐p1 promotes the formation of spherical structures composed by densely packed prism‐like crystals, which revealed a Ca/P ratio of 1.56, corresponding to HA. FTIR‐ATR showed predominant spectrum peaks that correspond and are characteristic of HA and octacalcium phosphate (OCP). Analysis by XRD indicates that the crystals show planes with a preferential crystalline orientation for HA and for OCP. HRTEM showed interplanar distances that correspond to crystalline planes of HA and OCP. Crystals are composed by superimposed lamellae, which exhibit epitaxial growth, and each layer of the crystals is structured by nanocrystals. This study reveals that CEMP1‐p1 regulates HA crystal formation, somehow mimicking the in vivo process of mineralized tissues bioformation. 相似文献
17.
《Animal : an international journal of animal bioscience》2017,11(12):2309-2319
Blood serum proteins are significant indicators of animal health. Nevertheless, several factors should be considered to appropriately interpret their concentrations in blood. Therefore, the objectives of this study were (1) to assess the effect of herd productivity, breed, age and stage of lactation on serum proteins and (2) to investigate association between serum proteins and somatic cell count (SCC) in dairy cattle. Milk and blood samples were collected from 1508 cows of six different breeds (Holstein Friesian, Brown Swiss, Jersey, Simmental, Rendena and Alpine Grey) that were housed in 41 multi-breed herds. Milk samples were analyzed for composition and SCC, while blood samples were analyzed for serum proteins (i.e. total protein, albumin, globulin and albumin-to-globulin ratio (A : G)). Herds were classified as low or high production, according to the cow’s average daily milk energy yield adjusted for breed, days in milk (DIM) and parity. Data were analyzed using a linear mixed model that included the fixed effects of DIM, parity, SCS, breed, herd productivity and the random effect of the Herd-test date within productivity level. Cows in high producing herds (characterized also by greater use of concentrates in the diet) had greater serum albumin concentrations. Breed differences were reported for all traits, highlighting a possible genetic mechanism. The specialized breed Jersey and the two dual-purpose local breeds (Alpine Grey and Rendena) had the lowest globulin concentration and greatest A : G. Changes in serum proteins were observed through lactation. Total protein reached the highest concentration during the 4th month of lactation. Blood albumin increased with DIM following a quadratic pattern, while globulin decreased linearly. As a consequence, A : G increased linearly during lactation. Older cows had greater total protein and globulin concentrations, while albumin concentration seemed to be not particularly affected by age. A linear relationship between serum proteins and SCS was observed. High milk SCS was associated with greater total protein and globulin concentrations in blood. The rise in globulin concentration, together with a decrease in albumin concentrations, resulted in a decline in A : G as SCS of milk increased. In conclusion, such non-genetic factors must be considered to appropriately interpret serum proteins as potential animal welfare indicator and their evaluation represents an important first-step for future analysis based on the integration of metabolomics, genetic and genomic information for improving the robustness of dairy cows. 相似文献
18.
Douglas S. Rehder Randall W. Nelson Chad R. Borges 《Protein science : a publication of the Protein Society》2009,18(10):2036-2042
On the basis of the results of activity studies, previous reports have suggested that vitamin D binding protein (DBP) is significantly or even completely deglycosylated in cancer patients, eliminating the molecular precursor of the immunologically important Gc macrophage activating factor (GcMAF), a glycosidase‐derived product of DBP. The purpose of this investigation was to directly determine the relative degree of O‐linked trisaccharide glycosylation of serum‐derived DBP in human breast, colorectal, pancreatic, and prostate cancer patients. Results obtained by electrospray ionization‐based mass spectrometric immunoassay showed that there was no significant depletion of DBP trisaccharide glycosylation in the 56 cancer patients examined relative to healthy controls. These results suggest that alternative hypotheses regarding the molecular and/or structural origins of GcMAF must be considered to explain the relative inability of cancer patient serum to activate macrophages. 相似文献
19.
The increased application of nanomaterials has raised the level of public concern regarding possible toxicities caused by exposure to nanostructures. The interactions of nanosized hydroxyapatite (HA) with cytochrome c and hemoglobin were investigated by zeta-potential, UV-vis, fluorescence and circular dichroism. The experimental results indicated that the interactions were formed via charge attraction and hydrogen bond and obeyed Langmuir adsorption isotherm. The two functional proteins bridged between HA particles to aggregate into the coralloid form, where change of the secondary structure of proteins occurred. From effects of nanosized HA, SiO(2) and TiO(2) particles on the zebrafish embryos development, they were adsorbed on the membrane surface confirmed by the electronic scanning microscopy. Nano-HA aggregated into the biggest particles around the membrane protein and then caused a little toxicity to development of zebrafish embryos. The SiO(2) particles were distributed throughout the outer surface and caused jam of membrane passage, delay of the hatching time and axial malformation. Maybe owing to the oxygen free radical activity, TiO(2) caused some serious deformity characters in the cardiovascular system. 相似文献
20.
Antibody preparations against rat acute phase proteins were tested for cross reactivity with other serum proteins, including rat albumin. Rabbit anti-rat a alpha1-acid glycoprotein and ceruloplasmin IgG purified on protein A-Sepharose did not show any cross reactivity with rat albumin, hemoglobin or transferrin. Rabbit anti-rat haptoglobin and -macroglobulin IgG purified on protein A-Sepharose showed a 39% and 30% cross reactivity with rat albumin and a 20% and 19% cross reactivity with rat hemoglobin. Because these proteins in whole serum were not adsorbed on Cibacron Blue F3-GA Sepharose, the albumin would be adsorbed on Cibacron Blue F3-GA Sepharose by the use of whole rat serum. Rabbit anti-rat haptoglobin and alpha2-macroglobulin IgG showing cross reactivity with albumin was simply eliminated. 相似文献