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Biotechnology Progress

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https://www.readbyqxmd.com/read/28220676/cho-cells-adapted-to-inorganic-phosphate-limitation-show-higher-growth-and-higher-pyruvate-carboxylase-flux-in-phosphate-replete-conditions
#1
Vishwanathgouda Maralingannavar, Dharmeshkumar Parmar, Tejal Pant, Chetan Gadgil, Venkateswarlu Panchagnula, Mugdha Gadgil
Inorganic phosphate (Pi ) is an essential ion involved in diverse cellular processes including metabolism. Changes in cellular metabolism upon long term adaptation to Pi limitation have been reported in E. coli. Given the essential role of Pi , adaptation to Pi limitation may also result in metabolic changes in animal cells. In this study, we have adapted CHO cells producing recombinant IgG to limiting Pi conditions for 75 days. Not surprisingly, adapted cells showed better survival under Pi limitation. Here, we report the finding that such cells also showed better growth characteristics compared to control in batch culture replete with Pi (higher peak density and integral viable cell density), accompanied by a lower specific oxygen uptake rate and cytochrome oxidase activity towards the end of exponential phase...
February 21, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28218499/fine-tuning-sortase-mediated-immobilization-of-protein-layers-on-surfaces-using-sequential-deprotection-and-coupling
#2
Maryam Raeeszadeh-Sarmazdeh, Ranganath Parthasarathy, Eric T Boder
Increasing interest in protein immobilization on surfaces has heightened the need for techniques enabling layer-by-layer protein attachment. Here, we report a technique for controlling enzyme-mediated immobilization of layers of protein on the surface using a genetically-encoded protecting group. An enterokinase-cleavable peptide sequence was inserted at the N-terminus of bifunctional fluorescent proteins containing Sortase A substrate recognition tags at both ends to control Sortase A-mediated protein immobilization on the surface layer-by-layer...
February 20, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28218470/maximizing-the-functional-lifetime-of-protein-a-resins
#3
Jennifer Zhang, Sethu Siva, Ryan Caple, Rob Gronke, Sanchayita Ghose
Protein A chromatography is currently the industry gold-standard for monoclonal antibody and Fc-fusion protein purification. The high cost of Protein A however makes resin lifetime and resin reuse an important factor for process economics. Typical resin lifetime studies performed in the industry usually examine the effect of resin re-use on binding capacity, yield, and product quality without answering the fundamental question of what is causing the decrease in performance. A two part mechanistic study was conducted in an attempt to decouple the effect of the two possible factors (resin hydrolysis and/or degradation vs...
February 20, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28188705/design-construction-and-optimization-of-a-novel-modular-and-scalable-incubation-chamber-for-continuous-viral-inactivation
#4
Raquel Orozco, Linus Amarikwa, Stephanie Parker, Scott Godfrey, Lindsay Hernandez, Chinenye Wachuku, Ben Mai, Brian Song, Shashidhar Hoskatti, Jinkeng Asong, Marcus Fiadeiro, Parviz Shamlou, Cameron Bardliving, Jon Coffman
We designed, built or 3D printed, and screened tubular reactors that minimize axial dispersion to serve as incubation chambers for continuous virus inactivation of biological products. Empirical residence time distribution data were used to derive each tubular design's volume equivalent to a theoretical plate (VETP) values at a various process flow rates. One design, the Jig In a Box (JIB), yielded the lowest VETP, indicating optimal radial mixing and minimal axial dispersion. A minimum residence time (MRT) approach was employed, where the MRT is the minimum time the product spends in the tubular reactor...
February 11, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28188702/control-of-chitin-nanofiber-production-by-the-lipid-producing-diatom-cyclotella-sp-through-fed-batch-addition-of-dissolved-silicon-and-nitrate-in-a-bubble-column-photobioreactor
#5
Omar Chiriboga, Gregory L Rorrer
Diatoms are single-celled algae that make cell walls of nanopatterned biogenic silica called frustules through metabolic uptake of dissolved silicon and its templated condensation into biosilica. The centric marine diatom Cyclotella sp. also produces intracellular lipids and the valued co-product chitin, an N-acetyl glucosamine biopolymer that is extruded from selected frustule pores as pure nanofibers. The goal of this study was to develop a nutrient feeding strategy to control the production of chitin nanofibers from Cyclotella with the co-production of biofuel lipids...
February 11, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28188696/applied-in-situ-product-recovery-in-abe-fermentation
#6
REVIEW
Victoria Outram, Carl-Axel Lalander, Jonathan G M Lee, E Timothy Davies, Adam P Harvey
The production of biobutanol is hindered by the product's toxicity to the bacteria, which limits the productivity of the process. In situ product recovery of butanol can improve the productivity by removing the source of inhibition. This paper reviews in situ product recovery techniques applied to the acetone butanol ethanol fermentation in a stirred tank reactor. Methods of in situ recovery include gas stripping, vacuum fermentation, pervaporation, liquid-liquid extraction, perstraction and adsorption, all of which have been investigated for the acetone, butanol and ethanol fermentation...
February 11, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28188692/bioreactor-scale-up-and-protein-product-quality-characterization-of-piggybac-transposon-derived-cho-pools
#7
Yashas Rajendra, Sowmya Balasubramanian, Robert B Peery, James R Swartling, Neil A McCracken, Dawn L Norris, Christopher C Frye, Gavin C Barnard
Chinese hamster ovary (CHO) cells remain the most popular host for the production of biopharmaceutical drugs, particularly monoclonal antibodies (mAbs), bispecific antibodies and Fc-fusion proteins. Creating and characterizing the stable CHO clonally-derived cell lines (CDCLs) needed to manufacture these therapeutic proteins is a lengthy and laborious process. Therefore, CHO pools have increasingly been used to rapidly produce protein to support and enable preclinical drug development. We recently described the generation of CHO pools yielding mAb titers as high as 7...
February 11, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28188688/evaluation-of-heavy-chain-c-terminal-deletions-on-productivity-and-product-quality-of-monoclonal-antibodies-in-chinese-hamster-ovary-cho-cells
#8
Zhilan Hu, Danming Tang, Shahram Misaghi, Guoying Jiang, Christopher Yu, Mandy Yim, David Shaw, Brad Snedecor, Michael Laird, Amy Shen
Monoclonal antibodies (mAbs) have been well established as potent therapeutic agents and are used to treat many different diseases. During cell culture production, antibody charge variants can be generated by cleavage of heavy chain (HC) C-terminal lysine and proline amidation. Differences in levels of charge variants during manufacturing process changes make it challenging to demonstrate process comparability. In order to reduce heterogeneity and achieve consistent product quality, we generated and expressed antibodies with deletion of either HC C-terminal lysine (-K) or lysine and glycine (-GK)...
February 11, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28187511/a-novel-cholesterol-lipid-delivery-system-for-murine-myeloma-cell-lines
#9
Gaurav Chauhan, Albert E Schmelzer
Murine myeloma NS0 cells are cholesterol-dependent auxotrophs and require externally provided cholesterol for sustained growth. Traditionally, cholesterol is provided to these cells by supplementing cell culture media with concentrated solution of cholesterol and other water insoluble components dissolved in 200-proof ethanol. However, the solubility of cholesterol in ethanol is limited and for processes requiring large amounts of cholesterol, the consequential increase in added ethanol may negatively impact cell growth...
February 10, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28127952/shock-treatment-of-corn-stover
#10
Austin Bond, Hema Rughoonundun, Eric Petersen, Carol Holtzapple, Mark Holtzapple
Corn stover digestibility was enhanced via shock treatment. A slurry of lime-treated corn stover was placed in a partially filled closed vessel. From the ullage space, either a shotgun shell was fired into the slurry, or a gas mixture was detonated. Various conditions were tested (i.e., pressures, depth, solids concentrations, gas mixtures). A high pressurization rate (108,000 MPa/s shotgun shells; 4,160,000 MPa/s hydrogen/oxygen detonation) was the only parameter that improved enzymatic digestibility. Stoichiometric propane/air deflagration had a low pressurization rate (37...
January 27, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28127897/cell-free-translational-screening-of-an-expression-sequence-tag-library-of-clonorchis-sinensis-for-novel-antigen-discovery
#11
Devi Kasi, Christy Catherine, Seung-Won Lee, Kyung-Ho Lee, Yu Jung Kim, Myeong Ro Lee, Jung Won Ju, Dong-Myung Kim
The rapidly evolving cloning and sequencing technologies have enabled understanding of genomic structure of parasite genomes, opening up new ways of combatting parasite-related diseases. To make the most of the exponentially accumulating genomic data, however, it is crucial to analyze the proteins encoded by these genomic sequences. In this study, we adopted an engineered cell-free protein synthesis system for large-scale expression screening of an expression sequence tag (EST) library of Clonorchis sinensis to identify potential antigens that can be used for diagnosis and treatment of clonorchiasis...
January 27, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28127895/a-robust-feeding-strategy-to-maintain-set-point-glucose-in-mammalian-fed-batch-cultures-when-input-parameters-have-a-large-error
#12
Viktor Konakovsky, Christoph Clemens, Markus Michael Müller, Jan Bechmann, Christoph Herwig
Industrial CHO cell cultures run under fed-batch conditions are required to be controlled in particular ranges of glucose, while glucose is constantly consumed and must be replenished by a feed. The most appropriate feeding rate is ideally stoichiometric and adaptive in nature to balance the dynamically changing rate of glucose consumption. However, high errors in biomass and glucose estimation as well as limited knowledge of the true metabolic state challenge the control strategy. In this contribution, we take these errors into account and simulate the output with uncertainty trajectories in silico in order to control glucose concentration...
January 27, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28127893/towards-the-design-of-an-optimal-strategy-for-the-production-of-ergosterol-from-saccharomyces-cerevisiae-yeasts
#13
Jan Náhlík, Pavel Hrnčiřík, Jan Mareš, Mojmír Rychtera, Christopher A Kent
The total yield of ergosterol produced by the fermentation of the yeast Saccharomyces cerevisiae depends on the final amount of yeast biomass and the ergosterol content in the cells. At the same time ergosterol purity - defined as percentage of ergosterol in the total sterols in the yeast - is equally important for efficient downstream processing. This study investigated the development of both the ergosterol content and ergosterol purity in different physiological (metabolic) states of the microorganism S...
January 27, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28127892/taming-hyperactive-hdnase-i-stable-inducible-expression-of-a-hyperactive-salt-and-actin-resistant-variant-of-human-deoxyribonuclease-i-in-cho-cells
#14
Cynthia Lam, Lydia Santell, Blair Wilson, Mandy Yim, Salina Louie, Danming Tang, David Shaw, Pamela Chan, Robert A Lazarus, Brad Snedecor, Shahram Misaghi
While the most common causes of clonal instability are DNA copy number loss and silencing, toxicity of the expressed protein(s) may also induce clonal instability. Human DNase I (hDNase I) is used therapeutically for the treatment of cystic fibrosis (CF) and may have potential benefit for use in systemic lupus erythematosus (SLE). hDNase I is an endonuclease that catalyzes degradation of extracellular DNA and is inhibited by both salt and G-actin. Engineered versions of hDNase I, bearing multiple point mutations, which renders them Hyperactive, Salt- and Actin-Resistant (HSAR-hDNase I) have been developed previously...
January 27, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28054475/design-and-control-of-integrated-chromatography-column-sequences
#15
Niklas Andersson, Anton Löfgren, Marianne Olofsson, Anton Sellberg, Peter Tiainen, Bernt Nilsson
To increase the productivity in biopharmaceutical production a natural step is to introduce integrated continuous biomanufacturing which leads to fewer buffer and storage tanks, smaller sizes of integrated unit operations and full automation of the operation. The main contribution of this work is to illustrate a methodology for design and control of a downstream process based on integrated column sequences. For small scale production, e.g. pre-clinical studies, integrated column sequences can be implemented on a single chromatography system...
January 5, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28054473/-screening-different-host-cell-lines-for-the-dynamic-production-of-measles-virus
#16
Tanja A Grein, Felix Schwebel, Marco Kress, Daniel Loewe, Hauke Dieken, Denise Salzig, Tobias Weidner, Peter Czermak
Measles virus (MV) has a natural affinity for cancer cells and oncolytic MV preparations have therefore been investigated in several clinical trials as a potential treatment for cancer. The main bottleneck in the administration of oncolytic MV to cancer patients is the production process, because very large doses of virus particles are required for each treatment. Here we investigated the productivity of different host cells and found that a high infection efficiency did not necessarily result in high virus yields because virus release is also dependent on the host cell...
January 5, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28054464/economic-improvement-of-continuous-pharmaceutical-production-via-the-optimal-control-of-a-multi-feed-bioreactor
#17
Jonathan P Raftery, Melanie R DeSessa, M Nazmul Karim
Projections on the profitability of the pharmaceutical industry predict a large amount of growth in the coming years. Stagnation over the last 20 years in product development has led to the search for new processing methods leading to improvements in profitability by the reduction of operating costs or the improvement of process productivity. This work proposes a novel multi-feed bioreactor system composed of independently controlled feeds for substrate(s) and media used as a supplement and allows for the free manipulation of the bioreactor supply rate and substrate concentrations to maximize bioreactor productivity and substrate utilization while reducing operating costs...
January 5, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28054462/optimization-of-biopharmaceutical-downstream-processes-supported-by-mechanistic-models-and-artificial-neural-networks
#18
Silvia M Pirrung, Luuk A M van der Wielen, Ruud F W C Van Beckhoven, Emile J A X van de Sandt, Michel H M Eppink, Marcel Ottens
Downstream process development is a major area of importance within the field of bioengineering. During the design of such a downstream process, important decisions have to be made regarding the type of unit operations as well as their sequence and their operating conditions. Current computational approaches addressing these issues either show a high level of simplification or struggle with computational speed. Therefore, this article presents a new approach that combines detailed mechanistic models and speed-enhancing artificial neural networks...
January 5, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28019710/mammalian-cell-culture-monitoring-using-in-situ-spectroscopy-is-your-method-really-optimised
#19
Silvère André, Sylvain Lagresle, Zahia Hannas, Éric Calvosa, Ludovic Duponchel
In recent years, as a result of the process analytical technology (PAT) initiative of the US Food and Drug Administration (FDA), many different works have been carried out on direct and in situ monitoring of critical parameters for mammalian cell cultures by Raman spectroscopy and multivariate regression techniques. However, despite interesting results, it cannot be said that the proposed monitoring strategies, which will reduce errors of the regression models and thus confidence limits of the predictions, are really optimized...
December 26, 2016: Biotechnology Progress
https://www.readbyqxmd.com/read/28019701/current-state-and-perspectives-in-modeling-and-control-of-human-pluripotent-stem-cell-expansion-processes-in-stirred-tank-bioreactors
#20
REVIEW
Vytautas Galvanauskas, Vykantas Grincas, Rimvydas Simutis, Yuki Kagawa, Masahiro Kino-Oka
Implementation of model-based practices for process development, control, automation, standardization, and validation are important factors for therapeutic and industrial applications of human pluripotent stem cells. As robust cultivation strategies for pluripotent stem cell expansion and differentiation have yet to be determined, process development could be enhanced by application of mathematical models and advanced control systems to optimize growth conditions. Therefore, it is important to understand both the potential of possible applications and the apparent limitations of existing mathematical models to improve pluripotent stem cell cultivation technologies...
December 26, 2016: Biotechnology Progress
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