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Full-Text Articles in Engineering

Identification And Characterization Of Calcium And Manganese Transporting Atpase (Pmr1) Gene Of Pichia Pastoris, Michael P. Dux, Mehmet Inan Feb 2007

Identification And Characterization Of Calcium And Manganese Transporting Atpase (Pmr1) Gene Of Pichia Pastoris, Michael P. Dux, Mehmet Inan

Papers in Biotechnology

A gene homologous to Saccharomyces cerevisiae PMR1 has been cloned in the methylotrophic yeast Pichia pastoris.The entire P. pastoris PMR1 gene (PpPMR1 ) codes a protein of 924 amino acids. Sequence analysis of the PpPMR1 cDNA and the genomic DNA revealed that there is no intron in the coding region. The putative gene product contains all of the conserved regions observed in P-type ATPases and exhibits 66.2%, 60.3% and 50.6% identity to Pichia angusta (Hansenula polymorpha), Saccharomyces cerevisiae PMR1 and human ATP2C1 gene products, respectively. A pmr1 null mutant strain of P. pastoris exhibited growth defects in media with the …


Use Of A Modified Zirconia Support In The Separation Of Immunoproteins, Anuradha Subramanian, Sabyasachi Sarkar Mar 2006

Use Of A Modified Zirconia Support In The Separation Of Immunoproteins, Anuradha Subramanian, Sabyasachi Sarkar

Papers in Biotechnology

Zirconia beads (25–38 μm in diameter) were modified with N,N,N′,N′-ethylenediaminetetramethylenephosphonic acid to generate a zirconia based pseudoaffinity support, further referred to as r_PEZ. The influence of pH, salt concentration and temperature on the binding of human immunoglobulin G (hIgG) to r_PEZ was studied. Temperature had no significant impact on the maximum binding capacity (Qmax), and the equilibrium-binding constant (Kd), whereas pH and the salt concentration had a noticeable impact on both Qmax and Kd. The Qmax value of 55 mg hIgG/ml of bead was obtained at a pH of 5.5 and found to decrease with an increase of pH. The …


A Comparative Study Of Monoclonal Antibodies (Mabs) Purified From Cell Culture Supernatant On Edtpa-Modified Zirconia Beads And Protein A-Hyper D Support, Anuradha Subramanian, Blanca Martinez, Jill Holm, Peter W. Carr, Clayton V. Mcneff Mar 2006

A Comparative Study Of Monoclonal Antibodies (Mabs) Purified From Cell Culture Supernatant On Edtpa-Modified Zirconia Beads And Protein A-Hyper D Support, Anuradha Subramanian, Blanca Martinez, Jill Holm, Peter W. Carr, Clayton V. Mcneff

Papers in Biotechnology

Colloidal zirconia was spray dried to yield zirconia particles, which were further modified with N, N, N0, N0- Ethylenediamine tetra methylenephosphonic acid (EDTPA) to yield a sup-port for use in bioseparations. EDTPA modified zirconia particles will be further referred to as, r_PEZ. Cell culture supernatants rich in monoclonal antibody (Mab) subtypes IgG1, IgG2a, IgG2b, and IgG3 were chromatographed on a r_PEZ column, and on a protein A-hyper D col-umn that was purchased commercially. All Mab subtypes bound to r_PEZ and process yields in the range of 88 to 99% were obtained. The purity of the Mab products were ascertained by …


Crosslinked Chitosan: Its Physical Properties And The Effects Of Matrix Stiffness On Chondrocyte Cell Morphology And Proliferation, Anuradha Subramanian, Hsin-Yi Lin Aug 2005

Crosslinked Chitosan: Its Physical Properties And The Effects Of Matrix Stiffness On Chondrocyte Cell Morphology And Proliferation, Anuradha Subramanian, Hsin-Yi Lin

Papers in Biotechnology

Chitosan [<(1-4)-2 amino-2-deoxy-d-glucose], the natural polyaminosaccharide derived from N-deacetylation of chitin [<(1-4)-2 acetamide-2-deoxy-d-glucose], has been shown to possess attractive biological and cell interactive properties. Recently chitosan and chitosan analogs have also been shown to support the growth and continued function of chondrocytes. In the present study, chitosan substrates are crosslinked with a func-tional diepoxide (1,4 butanediol diglycidyl ether) to alter its mechanical property, and the viability and proliferation of the canine articular chondrocytes seeded on the crosslinked surface are further assayed. Of interest is the impact of substrate stiffness on the growth and proliferation of articular canine chondrocytes. Cross linked scaffolds were also sub-jected to degradation by chitosanase to examine the impact of cross linking on enzyme- assisted degradation. The hydrophilicity and compression modulus of the crosslinked sur-faces were measured via contact-angle measurements and compression tests, respec-tively. Scanning electron microscopy (SEM) and fluorescent staining were used to ob-serve the proliferation and morphology of chondrocyte cells on noncrosslinked and crosslinked surfaces. The crosslinked chitosan was found to be nontoxic to chondrocytes and more hydrophilic. Its compression modulus and stiffness increased, which may im-prove the scaffold resistance to wear and in vivo shrinkage once implanted. The in-creased stiffness also seemed to serve as an additional mechanical stimulus to promote chondrocyte growth and proliferation. The cell morphology on crosslinked scaffolds seen by SEM and fluorescent stain was the typical chondrocytic rounded shape. The method proposed provides a nontoxic way to increase the mechanical strength of the chitosan scaffolds.


Chromatographic Purification Of Mabs With Non-Affinity Supports, Anuradha Subramanian Jun 2005

Chromatographic Purification Of Mabs With Non-Affinity Supports, Anuradha Subramanian

Papers in Biotechnology

The introduction of new protein-based therapeutics such as monoclonal antibodies (MAbs), MAb-based vaccines, growth factors and plasma proteins implies the need to study, characterize, and purify. The separation step is likely to be a bottleneck and cost-effective technology will be needed to rectify it. The currently prevalent matrices for chromatographic separation of immunoglobulins (Igs) are based on Protein A or its recombinant versions (Protein G). They display excellent selectivity and specificity, but are expensive. A Protein A matrix costs $8,000 to 12,000 per L-resin. The typical production column volume is 100 L. The million-dollar matrix is far more expensive than …


Uv-Vis -Infrared Optical And Afm Study Of Spin-Cast Chitosan Films, W H. Nosal, D. W. Thompson, Sabyasachi Sarkar, Anuradha Subramanian, John A. Woollam, L Yan Jun 2005

Uv-Vis -Infrared Optical And Afm Study Of Spin-Cast Chitosan Films, W H. Nosal, D. W. Thompson, Sabyasachi Sarkar, Anuradha Subramanian, John A. Woollam, L Yan

Papers in Biotechnology

Optical properties OS spin-cast chitosan films have been determined in the infrared, visible, and ultraviolet region or the spectrum ~tsing spectroscopic ellipsometry. Optical constants for the Vvis-near IR spectra from 130 to 1700 nm were determined using Cauchy dispersion forms com-bined with Lorentzian oscillator models in the absorptive shorler wavelength regions. Infrared ndex of refraction and extinction coefficients from 750 to 4000cm-' were determined using ellip-sometric data fits to dispersion models based on harmonic oscillators. This modeling determined that optical onisotropy was present and measurable over all wavelength regions of ellipsomctric data. To obtain information on the micro- and nano-scale …


Modeling Of Immunoglobulin Uptake By N,N,N′,N′-Ethylenediaminetetramethylenephosphonic Acid-Modified Zirconia Particles Under Static And Dynamic Conditions, Sabyasachi Sarkar, Anuradha Subramanian May 2005

Modeling Of Immunoglobulin Uptake By N,N,N′,N′-Ethylenediaminetetramethylenephosphonic Acid-Modified Zirconia Particles Under Static And Dynamic Conditions, Sabyasachi Sarkar, Anuradha Subramanian

Papers in Biotechnology

A matrix developed from N,N,N′,N′-ethylenediaminetetramethylenephosphonic acid-modified zirconia beads (further referred to as r_PEZ); 25–38 μm in diameter and with a pore size of 22 ± 3 nm, was utilized for the separation of immunoglobulins (Igs). r_PEZ has been shown to bind to various Igs originating from a wide variety of species. To understand the mechanisms controlling the uptake of Igs by r_PEZ, static protein uptake experiments were carried out. The protein uptake profiles were further modeled with a kinetic rate constant model. Individual studies were undertaken for human immunoglobulin A, G and M (HIgA, HIgG and HIgM). The kinetic rate …


The Use Of Confocal Laser Scanning Microscopy To Study The Transport Of Biomacromolecules In A Macroporous Support, Anuradha Subramanian, Jennifer Hommerding Apr 2005

The Use Of Confocal Laser Scanning Microscopy To Study The Transport Of Biomacromolecules In A Macroporous Support, Anuradha Subramanian, Jennifer Hommerding

Papers in Biotechnology

Large-pore materials or supports resembling polymer conduits are used as packing material in chromatographic operations. Our ongoing research has shown that, when modified with peptides or ligands, chitosan beads that are 800 m in diameter and have 3.5% solids can be used as matrices in bioseparations. The goal of the present study is to evaluate the transport properties of biomolecules in the modified chitosan beaded matrices. Batch uptake experiments with fluorescently tagged pure human IgG, human IgA and human IgM were conducted to visualize the distribution of binding sites throughout the bead as well as to evaluate restrictions to diffusion, …


Identification Of The Mass Transfer Mechanisms Involved In The Transport Of Human Immunoglobulin - G In N,N,N',N' -Ethylnediaminetetramenthylenephosphonic Acid Modified Zirconia, Sabyasachi Sarkar, Perer W. Carr, Anuradha Subramanian Apr 2005

Identification Of The Mass Transfer Mechanisms Involved In The Transport Of Human Immunoglobulin - G In N,N,N',N' -Ethylnediaminetetramenthylenephosphonic Acid Modified Zirconia, Sabyasachi Sarkar, Perer W. Carr, Anuradha Subramanian

Papers in Biotechnology

Zirconia particles modified with N,N,N′,N′-ethylenediaminetetramethylenephosphonic acid (EDTPA), further referred to as r_PEZ, were studied as a support material for use in chromatography. Our previous studies have demonstrated the utility of r_PEZ in the separation of immunoglobulins from biological fluids. In the present study we sought to understand the underlying factors and identify the rate-limiting mechanisms that govern the transport of biomolecules in r_PEZ. Pulse injection techniques were used to elucidate the individual mass transfer parameters. Elution profiles obtained under retained and unretained conditions were approximated by the Gaussian equation and the corresponding HETP contributions were estimated. The dependence of …


Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander Jan 2005

Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander

Papers in Biotechnology

Transgenic animals secreting individual chains and assembled fibrinogen were produced to evaluate the capacity of the mammary gland for maximizing assembly, glycosylation and secretion of recombinant human fibrinogen (rhfib). Transgenes were constructed from the 4.1 kbp murine Whey Acidic Protein promoter (mWAP) and the three cDNAs coding for the Aα,Bβ and γ fibrinogen chains. Transgenic mice secreted fully assembled fibrinogen into milk at concentrations between 10 and 200 μg/ml, with total secretion of subunits approaching 700 μ g/ml in milk. Partially purified fibrinogen was shown to form a visible and stable clot after treatment with human thrombin and factor XIII. …


Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander Jan 2005

Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander

Papers in Biotechnology

Transgenic animals secreting individual chains and assembled fibrinogen were produced to evaluate the capacity of the mammary gland for maximizing assembly, glycosylation and secretion of recombinant human fibrinogen (rhfib). Transgenes were constructed from the 4.1 kbp murine Whey Acidic Protein promoter (mWAP) and the three cDNAs coding for the Aα,Bβ and γ fibrinogen chains. Transgenic mice secreted fully assembled fibrinogen into milk at concentrations between 10 and 200 μg/ml, with total secretion of subunits approaching 700 μ g/ml in milk. Partially purified fibrinogen was shown to form a visible and stable clot after treatment with human thrombin and factor XIII. …


Preparation And Evaluation Of The Electrospun Chitosan/Peo Fibers For Potential Applications In Cartilage Tissue Engineering, Anuradha Subramanian, David Vu, Gustavo F. Larsen, Hsin Yii Lin Jan 2005

Preparation And Evaluation Of The Electrospun Chitosan/Peo Fibers For Potential Applications In Cartilage Tissue Engineering, Anuradha Subramanian, David Vu, Gustavo F. Larsen, Hsin Yii Lin

Papers in Biotechnology

Fibrous materials have morphological similarities to natural cartilage extracellular matrix and have been considered as candidate for bone tissue engineering scaffolds. In this study, we have evaluated a novel electrospun chitosan mat composed of oriented sub-micron fibers for its tensile property and biocompatibility with chondrocytes (cell attachment, proliferation and viability). Scanning electronic microscope images showed the fibers in the electrospun chitosan mats were indeed aligned and there was a slight cross-linking between the parent fibers. The electrospun mats have significantly higher elastic modulus (2.25 MPa) than the cast films (1.19 MPa). Viability of cells on the electrospun mat was 69% …


Causes Of Proteolytic Degradation Of Secreted Recombinant Proteins Produced In Ethylotrophic Yeast Pichia Pastoris: Case Study With Recombinant Ovine Interferon-T, Jayanta Sinha, Bradley A. Plantz, Mehmet Inan, Michael Meagher Dec 2004

Causes Of Proteolytic Degradation Of Secreted Recombinant Proteins Produced In Ethylotrophic Yeast Pichia Pastoris: Case Study With Recombinant Ovine Interferon-T, Jayanta Sinha, Bradley A. Plantz, Mehmet Inan, Michael Meagher

Papers in Biotechnology

It was observed that during fermentative production of recombinant ovine interferon-H (r-oIFN-H ) in Pichia pastoris, a secreted recombinant protein, the protein was degraded increasingly after 48 h of induction and the rate of degradation increased towards the end of fermentation at 72 h, when the fermentation was stopped. Proteases, whose primary source was the vacuoles, was found in in-creasing levels in the cytoplasm and in the fermentation broth after 48 h of induction and reached maximal values when the batch was completed at 72 h. Protease levels at various cell fractions as well as in the culture supernatant were …


Haemophilic Factors Produced By Transgenic Livestock: Abundance That Can Enable Alternative Therapies Worldwide, Kevin E. Van Cott, Paul E. Monahan, Timothy C. Nichols, William H. Velander Oct 2004

Haemophilic Factors Produced By Transgenic Livestock: Abundance That Can Enable Alternative Therapies Worldwide, Kevin E. Van Cott, Paul E. Monahan, Timothy C. Nichols, William H. Velander

Papers in Biotechnology

Haemophilia replacement factors, both plasma-derived and recombinant, are in relatively short supply and are high-cost products. This has stymied the study and development of alternative methods of administration of haemophilia therapy even in the most economically advanced countries, owing to the large amounts of material needed because bioabsorption and bioavailability of haemophilic factors can be less than 10% when using non-intravenous routes of delivery. There is therefore a need to increase access to therapy worldwide by decreasing the cost and increasing the abundance so that therapy can be achieved through simplified, alternative delivery methods. Transgenic livestock have been used to …


Production And Purification Of A Chimeric Monoclonal Antibody Against Botulinum Neurotoxin Serotype A , Mark C. Mowry, Michael Meagher Lead Investigator, Leonard Smith, Anuradha Subramanian Oct 2004

Production And Purification Of A Chimeric Monoclonal Antibody Against Botulinum Neurotoxin Serotype A , Mark C. Mowry, Michael Meagher Lead Investigator, Leonard Smith, Anuradha Subramanian

Papers in Biotechnology

Production of recombinant antibodies against botulinum neurotoxin is necessary for the development of a post-exposure treatment. CHO-DG44 cells were transfected with a plasmid encoding the light and heavy chains of a chimeric monoclonal antibody (S25) against botulism neurotoxin serotype A. Stable cell lines were obtained by dilution cloning and clones were shown to produce nearly equivalent levels of light and heavy chain antibody by an enzyme-linked immunosorbent assay (ELISA). In suspension culture, cells produced 35 μg/ml of chimeric antibody after 6 days, corresponding to a specific antibody productivity of 3.1 pg/cell/day. A method for the harvest and recovery of an …


Characterization And Optimization Of A Chromatographic Process Based On Ethylenediamine-N,N,N′,N′-Tetra(Methylphosphonic) Acid-Modified Zirconia Particles, Sabyasachi Sarkar, Peter W. Carr, Clayton V. Mcneff, Anuradha Subramanian Jun 2003

Characterization And Optimization Of A Chromatographic Process Based On Ethylenediamine-N,N,N′,N′-Tetra(Methylphosphonic) Acid-Modified Zirconia Particles, Sabyasachi Sarkar, Peter W. Carr, Clayton V. Mcneff, Anuradha Subramanian

Papers in Biotechnology

The primary objective of work was to characterize, optimize and model a chromatographic process based on ethylenediamine-N,N,N′,N′-tetra(methylphosphonic) acid (EDTPA)-modified zirconia particles. Zirconia particles were produced by spray-drying colloidal zirconia. Zirconia spheres produced were further classified, calcined and modified with EDTPA to yield a solid-phase support for use in bio-chromatography (r_PEZ). Specifically, the ability of r_PEZ to selectively bind and enrich IgG, IgA, and IgM from biological fluids was evaluated and demonstrated. To better understand the force of interaction between the IgG and the r_PEZ, the equilibrium disassociation constant (Kd) was determined by static binding isotherms, as a function of temperature …


Transgenic Non-Human Mammals Expressing Human Coagulation Factor Viii And Von Willebrand Factor, Henryk Lubon, William N. Drohan, William H. Velander Feb 2003

Transgenic Non-Human Mammals Expressing Human Coagulation Factor Viii And Von Willebrand Factor, Henryk Lubon, William N. Drohan, William H. Velander

Papers in Biotechnology

A non-human transgenic mammalian animal, as described above, contains an exogenous double stranded DNA sequence stably integrated into the genome of the animal, which comprises cis-acting regulatory units operably linked to a DNA sequence encoding human Factor VIII protein and a signal peptide, where the cis-acting regulatory units are active in mammary gland cells and the signal peptide is active in directing newly expressed Factor VIII into the milk of the animal. The promoter may be a milk protein promoter such as for whey acidic protein, casein, lactalbumin, or beta-lactoglobulin promoter. The transgenic mammals are preferably farm animals, for example, …


An Approach To Sequence Dna Without Tagging, Sanjun Niu, Ravi F. Saraf Sep 2002

An Approach To Sequence Dna Without Tagging, Sanjun Niu, Ravi F. Saraf

Papers in Biotechnology

Microarray technology is playing an increasingly important role in biology and medicine and its application to genomics for gene expression analysis has already reached the market with a variety of commercially available instruments. In these combinatorial analysis methods, known probe single-strand DNA (ssDNA) ‘primers’ are attached in clusters of typically 100 μm × 100 μm pixels. Each pixel of the array has a slightly different sequence. On exposure to ‘unknown’ target ssDNA, the pixels with the right complementary probe ssDNA sequence convert to double-stranded DNA (dsDNA) by a hybridization reaction. To transduct the conversion of the pixel to dsDNA, the …


Expression Of Active Human Factor Ix In Mammary Tissue And Of Milk Non Human Transgenic Mammals , William H. Velander, William N. Drohan Feb 2002

Expression Of Active Human Factor Ix In Mammary Tissue And Of Milk Non Human Transgenic Mammals , William H. Velander, William N. Drohan

Papers in Biotechnology

Recombinant Factor IX characterized by a high percentage of active protein can be obtained in the milk of transgenic animals that incorporate chimeric DNA molecules according to the present invention. Transgenic animals of the present invention are produced by introducing into developing embryos DNA that encodes Factor IX, such that the foreign DNA is stably incorporated in the DNA of germ line cells of the mature animal. Particularly efficient expression was accomplished using a chimeric construct comprising a mammary gland specific promoter, Factor IX cDNA that lacked the complete or any portion of the 5'-untranslated and 3'-untranslated region, which is …


Expression Of A Heterologous Protein C In Mammary Tissue Of Transgenic Animals Using A Long Whey Acidic Protein Promoter , William H. Velander, Henryk Lubton, William N. Drohan, Lothar Hennighausen Jul 2001

Expression Of A Heterologous Protein C In Mammary Tissue Of Transgenic Animals Using A Long Whey Acidic Protein Promoter , William H. Velander, Henryk Lubton, William N. Drohan, Lothar Hennighausen

Papers in Biotechnology

An isolated DNA sequence which regulates the expression of a heterologous gene composed of a mouse whey acidic protein promoter having a length of greater than about 2.4 kb extending upstream from the unique KpnI site in the mouse whey acidic protein gene is disclosed. Specifically a mouse whey acidic protein promoter of about 4.1-4.2 kb in length extending upstream from the unique KpnI site is preferred. This mouse whey acid protein promoter is operably linked to a DNA sequence encoding a heterologous polypeptide and used to prepare transgenic non-human mammals expressing the heterologous polypeptide in their milk. Particularly efficient …


Modeling Pichia Pastoris Growth On Methanol And Optimizing The Production Of A Recombinant Protein, The Heavy-Chain Fragment C Of Botulinum Neurotoxin, Serotype A, Wenhui Zhang, Mark A. Bevins, Bradley A. Plantz, Leonard A. Smith, Michael M. Meagher Oct 2000

Modeling Pichia Pastoris Growth On Methanol And Optimizing The Production Of A Recombinant Protein, The Heavy-Chain Fragment C Of Botulinum Neurotoxin, Serotype A, Wenhui Zhang, Mark A. Bevins, Bradley A. Plantz, Leonard A. Smith, Michael M. Meagher

Papers in Biotechnology

An unstructured growth model for the recombinant methylotrophic yeast P. pastoris Mut+ expressing the heavy-chain fragment C of botulinum neurotoxin serotype A [BoNT/A(Hc)], was successfully established in quasi-steady state fed-batch fermentations with varying cell densities. The model describes the relationships between specific growth rate and methanol concentration, and the relationships between specific methanol and ammonium consump-tion rates and specific growth rate under methanol-limited growth conditions. The maximum specific growth rate (μ) determined from the model was 0.08 h−1 at a methanol concentration of 3.65 g/L, while the actual maximum μ was 0.0709 h−1. The maximum specific methanol consumption rate was …


Immunoaffinity Chomatography, Anuradha Subramanian Apr 2000

Immunoaffinity Chomatography, Anuradha Subramanian

Papers in Biotechnology

Recent devclopments in recombinant DNA technology have enabled the synthesis of valuable therapeutic proteins in bacterial cells as well as in novel eucaryotic expression systems. However, the purification of proteins of interest from either the conventional sources, cell culture, or novel routes in a highly purified form necessitates the development of separation tcchniques capable of recovering proteins from these feed streams in a highly purified form (1,2). Purification of therapeutic proteins from biological sources is usually complicated by the presence of endogenous proteins (2). Purification methodologies based on ion exchange or adsorption serve as excellent prepurification steps, but they fail …


Purification Of Immunoglobulins From Serum Using Thiophilic Cellulose Beads, Anuradha Subramanian Jan 2000

Purification Of Immunoglobulins From Serum Using Thiophilic Cellulose Beads, Anuradha Subramanian

Papers in Biotechnology

This study evaluates the chromatographic performance of a support obtained by the reaction of mercaptoethanol with cellulose beads activated with divinyl sulfone. Cellulose beads 500-800 microns (pm) in diameter and with a solids content of 3.5% were selected for this study. A two-step sequence of permeation and reaction was used to install thiophilic sites throughout the cross section of the bead. The distribution of thiophilic sites was visualized by immobilizing fluorescent antibodies. Human and porcine serum proteins were separated on the thiophilic support at different linear velocities. Thiophilic cellulose beads were observed to bind human and porcine immunoglobulins (IgG) selectively …


Ranking The Factors Impacting Lmmunosorbent Performance, Anuradha Subramanian, William H. Velander Jan 2000

Ranking The Factors Impacting Lmmunosorbent Performance, Anuradha Subramanian, William H. Velander

Papers in Biotechnology

This work addresses the relative impact of the phenomena of orientation, multipoint attachment, and local density of the immobilized antibody 011 immunosorbent perfornnance. The masking of the antigen binding domains of monoclonal antibodies (Mab) by Fab Masking Antigens (FMAs) was used as a tool to determine the impact of orientation on the perforn~anceo f Emphaze, Affiprep'M, and Cellulose bead-based immunosorbents. A two-step antibody immobilization inethod involving permeation of the beaded matrix followed by a fast coupling reaction was used to study the effect of local density of the Mnh on immunosorbent efficiency. Lysyl groups on Mabs were covalently modified to …


Bioactivities Of A Tumour Necrosis Like Factor Released By Chicken Rnacrophages, Silke Rautenschlein, Anuradha Subramanian, Jagdev M. Sharma Jul 1999

Bioactivities Of A Tumour Necrosis Like Factor Released By Chicken Rnacrophages, Silke Rautenschlein, Anuradha Subramanian, Jagdev M. Sharma

Papers in Biotechnology

To test for tumour necrosis-like factor (TNF) of chickens, supernatants of a lipopolysaccharide (LPS)-stimulated chicken macrophage cell line MQ-NCSU were analysed. A sequence of ion-exchange and gel-permeation chromatography was utilised to isolate TNF-like activity from the culture supernatant. The peak of TNF-like cytotoxic activity corresponded to the fractions with a nlolecular weight of 81 kDa or higher. Polyclonal anti-human TNF-a antiserum cross-reacted by Western blotting with a 17 kDa protein in the TNF-containing fraction ~ ~ n d e denaturing conditions. This result indicated that chicken TNF-like factor in the biologically active form may be a protein multimer of monomers …


Bioactivities Of A Tumour Necrosis Like Factor Released By Chicken Macrophages, Silke Rautenschlein, Anuradha Subramanian, Jagdev M. Sharma Jul 1999

Bioactivities Of A Tumour Necrosis Like Factor Released By Chicken Macrophages, Silke Rautenschlein, Anuradha Subramanian, Jagdev M. Sharma

Papers in Biotechnology

To test for tumour necrosis-like factor (TNF) of chickens, supernatants of a lipopolysaccharide (LPS)-stimulated chicken macrophage cell line MQ-NCSU were analysed. A sequence of ion-exchange and gel-permeation chromatography was utilised to isolate TNF-like activity from the culture supernatant. The peak of TNF-like cytotoxic activity corresponded to the fractions with a nlolecular weight of 81 kDa or higher. Polyclonal anti-human TNF-a antiserum cross-reacted by Western blotting with a 17 kDa protein in the TNF-containing fraction ~ ~ n d e denaturing conditions. This result indicated that chicken TNF-like factor in the biologically active form may be a protein multimer of monomers …


Bovine Follicular Dynamics, Oocyte Recovery,And Development Of Oocytes Microinjected With A Green Fluorescent Protein Construct, M S. Chauhan, S Nadir, T L. Bailey, A W. Pryor, S P. Butler, D R. Notter, William H. Velander, F C. Gwazdauskas Jan 1999

Bovine Follicular Dynamics, Oocyte Recovery,And Development Of Oocytes Microinjected With A Green Fluorescent Protein Construct, M S. Chauhan, S Nadir, T L. Bailey, A W. Pryor, S P. Butler, D R. Notter, William H. Velander, F C. Gwazdauskas

Papers in Biotechnology

The present study was carried out to 1) evaluate the viability of in vitro fertilized zygotes after microinjection of DNA, 2) assess the influence of oocyte quality upon the development rate of embryos when injected with DNA, and 3) determine the integration frequency of green fluorescent protein DNA into microinjected embryos. Oocytes were aspirated from ovaries of nine nonlactating Holsteins and were categorized into grades A, B, C, and D. At 16 h after in vitro fertilization, approximately half of the pronuclear stage presumptive zygotes were classified as having 1 pronucleus or 2 pronuclei, and they were microinjected with DNA …


A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian Jan 1999

A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian

Papers in Biotechnology

A simple, sensitive, rapid (3 min), and highly reproducible solid-phase assay for the detection of proteins in the low nanogram range (4 ng) is described. The assay is based on differential Pon-ceau S staining of the protein spots on nitrocellulose and quantification of the protein- dye com-plexes on lubricated membranes using a densitometer. The dye solution used for protein stain-ing contained 0.1% Ponceau S in 15% phosphoric acid and 10% ethanol. Proteins were directly spotted onto pre- Ponceau S-stained nitrocellulose membranes, crosslinked with glutaraldehyde, rinsed in NaOH, restained with Ponceau S, and finished by rinsing in acid water at pH …


A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian Jan 1999

A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian

Papers in Biotechnology

A simple, sensitive, rapid (3 min), and highly reproducible solid-phase assay for the detection of proteins in the low nanogram range (4 ng) is described. The assay is based on differential Pon-ceau S staining of the protein spots on nitrocellulose and quantification of the protein- dye com-plexes on lubricated membranes using a densitometer. The dye solution used for protein stain-ing contained 0.1% Ponceau S in 15% phosphoric acid and 10% ethanol. Proteins were directly spotted onto pre- Ponceau S-stained nitrocellulose membranes, crosslinked with glutaraldehyde, rinsed in NaOH, restained with Ponceau S, and finished by rinsing in acid water at pH …


Crossflow Microfiltration Of Recombinant Escherichia Coli Lysates After High Pressure Homogenization, Stuart M. Bailey, Michael M. Meagher Nov 1997

Crossflow Microfiltration Of Recombinant Escherichia Coli Lysates After High Pressure Homogenization, Stuart M. Bailey, Michael M. Meagher

Papers in Biotechnology

Abstract: Crossflow membrane filtration was used to process recombinant Escherichia coli cell lysates containing protein inclusion bodies after high pressure homogenization. The number of passes through the high pressure homogenizer changed the viscosities and average particle sizes of the cell lysates. The different cell lysates were processed with a hollow fiber unit containing microfiltration membranes and a plate and frame unit with either ultrafiltration or microfiltration membranes. There were differences in permeate flux and protein transmission for the various membranes with the best performing membranes giving permeate fluxes greater than 60 L m−2 h−1 and protein transmissions greater than 90%. …