Effect of activation energy microheterogeneity on first-order enzyme deactivation.

abstract：:L-Threonine, a kind of essential amino acid, has numerous applications in food, pharmaceutical, and aquaculture industries. Fermentative l-threonine production from glucose has been achieved in Escherichia coli. However, there are still several limiting factors hindering further improvement of l-threonine productivity...

journal_title：Biotechnology and bioengineering

authors： Liu J,Li H,Xiong H,Xie X,Chen N,Zhao G,Caiyin Q,Zhu H,Qiao J

更新日期：2019-01-01 00:00:00

abstract：:In this article, a kinetic model is developed and presented for biological nutrient removal (BNR) activated sludge (BNRAS) systems in general, but for external nitrification (EN) BNRAS (ENBNRAS) systems in particular. The model is based on the UCTPHO model, but includes some significant modifications, such as anoxic P...

journal_title：Biotechnology and bioengineering

authors： Hu ZR,Wentzel MC,Ekama GA

更新日期：2007-12-15 00:00:00

abstract：:Strains from Trichoderma reesei have been used for cellulase production with a long history. It has been well known that cellulase biosynthesis by the fungal species is controlled through regulators, and elucidation of their regulation network is of great importance for engineering T. reesei with robust cellulase prod...

journal_title：Biotechnology and bioengineering

authors： Meng QS,Zhang F,Liu CG,Zhao XQ,Bai FW

更新日期：2020-06-01 00:00:00

abstract：:Based upon the general characteristics of the optimal feed rate profiles presented in an earlier article, efficient computational algorithms have been developed for fed-batch fermentation processes described by four or less mass balance equations. These algorithms make computations of optimal substrate feed rate profi...

journal_title：Biotechnology and bioengineering

authors： Lim HC,Tayeb YJ,Modak JM,Bonte P

更新日期：1986-09-01 00:00:00

abstract：:Polyhydroxyalkanoates (PHA) terployesters P(3HB-co-3HV-co-3HHx) consisting of 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), and 3-hydroxyhexanoate (3HHx) were produced by wild-type Aeromonas hydrophila 4AK4, its recombinant harboring PHA synthesis genes phaPCJ encoding PHA binding protein phasin, PHA synthase, and...

journal_title：Biotechnology and bioengineering

authors： Zhang HF,Ma L,Wang ZH,Chen GQ

更新日期：2009-10-15 00:00:00

abstract：:By investigating the effects of four operating variables-volume (V), Ultrafiltration flux (J), enzyme concentration (E), and substrate concentration (S)-on capacity (K) and conversion rate (epsilon) of a hollow fiber CSTR, the performances of the CSTR and the kinetic constants of the reaction were determined. A model ...

journal_title：Biotechnology and bioengineering

authors： Bressollier P,Petit JM,Julien R

更新日期：1988-05-01 00:00:00

abstract：:Murine hybridoma cells were grown in a bubble column that was inclined up to 45 degrees from vertical. Inclining the column by a few degrees separated the rising bubbles against the upper surface, leaving the bulk of the liquid bubble free. The liquid was circulated well by the rising bubbles, but collection of cells ...

journal_title：Biotechnology and bioengineering

authors： Lu GZ,Gray MR,Thompson BG,Suresh MR

更新日期：1995-01-20 00:00:00

abstract：:The feasibility of continuous ester synthesis in a membrane bioreactor (MBR) by a recombinant cutinase from Fusarium solani pisi was investigated, using the optimal conditions previously attained by medium engineering. The objective was to analyze the MBR behavior as a differential or an integral reactor. The main com...

journal_title：Biotechnology and bioengineering

authors： Carvalho CM,Aires-Barros MR,Cabral JM

更新日期：2001-01-20 00:00:00

abstract：:A comparative study of antimicrobial activity is done using three different electrospun nanofibers namely-CA, PAN, and PVC used as control and with various amounts of AgNO(3) being treated with UV-irradiation leading to the enhancement of silver nanoparticles. DMF is used as the common solvent which helps to undergo s...

journal_title：Biotechnology and bioengineering

authors： Lala NL,Ramaseshan R,Bojun L,Sundarrajan S,Barhate RS,Ying-Jun L,Ramakrishna S

更新日期：2007-08-15 00:00:00

abstract：:The misfolding of polypeptide chains and aggregation into the insoluble inclusion body state is a serious problem for biotechnology and biomedical research. Developing a rational strategy to control aggregation requires understanding the mechanism of polymerization. We investigated the in vitro aggregation of P22 tail...

journal_title：Biotechnology and bioengineering

authors： Speed MA,King J,Wang DI

更新日期：1997-05-20 00:00:00

abstract：:The mobility of water in intact biofilms was measured with pulsed field gradient nuclear magnetic resonance (PFG-NMR) and used to characterise their diffusive properties. The results obtained with several well-defined systems, viz. pure water, agar, and agar containing inert particles or active bacteria were compared ...

journal_title：Biotechnology and bioengineering

authors： Beuling EE,van Dusschoten D,Lens P,van den Heuvel JC,Van As H,Ottengraf SP

更新日期：1998-11-05 00:00:00

abstract：:Temperature shifting was investigated as a means of improving cloned-gene product yields form a recombinant Escherichia coli containing the temperature-sensitive plasmid, pOU 140. In a series of shaker flask fermentations recombinant cells were thermally induced for different time periods. The growth, stability, and p...

journal_title：Biotechnology and bioengineering

authors： Dipasquantonio VM,Betenbaugh MJ,Dhurjati P

更新日期：1987-03-01 00:00:00

abstract：:An extractive acetonobutylic fermentation process is developed by integrating bioproduction, Ultrafiltration, and distillation, providing simultaneous retention of biomass, selective removal of inhibitors from the permeate, as well as separation and purification of acetone-butanol-ethanol solvents. Successive batch fe...

journal_title：Biotechnology and bioengineering

authors： Minier M,Grateloup R,Blanc-Ferras E,Goma G

更新日期：1990-04-15 00:00:00

abstract：:Fed-batch cultures of recombinant microorganisms have attracted attention as they can separate cell growth stage from cloned-gene expression phase during fermentations. In this work, the effect of different glucose feeding strategies on cell growth and cloned gene expression was studied during aerobic fed-batch fermen...

journal_title：Biotechnology and bioengineering

authors： Patkar A,Seo JH

更新日期：1992-06-05 00:00:00

abstract：:Microcrystalline cellulose (10 g/L Avicel) was hydrolysed by two major cellulases, cellobiohydrolase I (CBH I) and endoglucanase II (EG II), of Trichoderma reesei. Two types of experiments were performed, and in both cases the enzymes were added alone and together, in equimolar mixtures. In time course studies the rea...

journal_title：Biotechnology and bioengineering

authors： Medve J,Karlsson J,Lee D,Tjerneld F

更新日期：1998-09-05 00:00:00

abstract：:We studied the resolution of racemic glycidol through esterification with butyric acid catalyzed by porcine pancreatic lipase in organic media. A screening of seven solvents (log P values between 0.49 and 3.0, P being the n-octanol-water partition coefficient of the solvent) showed that neither log P nor the logarithm...

journal_title：Biotechnology and bioengineering

authors： Martins JF,Da Ponte MN,Barreiros S

更新日期：1993-08-05 00:00:00

abstract：:The effect of trehalose (0.5 M) on the thermal stability of cutinase in the alkaline pH range was studied. The thermal unfolding induced by increasing temperature was analyzed in the absence and in the presence of trehalose according to a two-state model (which assumes that only the folded and unfolded states of cutin...

journal_title：Biotechnology and bioengineering

authors： Baptista RP,Cabral JM,Melo EP

更新日期：2000-12-20 00:00:00

abstract：:Overexpression of recombinant proteins in Escherichia coli often leads to a severe growth retardation of the host cells. The phage T7 promoter phi10 in a pET vector was utilized to express human superoxide dismutase. Induction with IPTG lead to an increase in protein content and cell size and a termination of cell div...

journal_title：Biotechnology and bioengineering

authors： Soriano E,Borth N,Katinger H,Mattanovich D

更新日期：2002-10-05 00:00:00

abstract：:Maintenance of high cell viability was the main characteristic of our new strains of thermotolerant Saccharomyces. Total sugar conversion to ethanol was observed for sugarcane juice fermentation at 38-40 degrees C in less than 10 h and without continuous aeration of the culture. Invertase activity differed among the s...

journal_title：Biotechnology and bioengineering

authors： Laluce C,Palmieri MC,Lopes da Cruz RC

更新日期：1991-03-15 00:00:00

abstract：:Production of cellulase using solid culture systems of Trichoderma reesei QM9414 and Sporotrichum cellulophilum on wheat bran was studied. By using moisture-controlled solid culture equipment, the effect of water content of wheat bran on cell growth and cellulase production was investigated. Cellular biomass grown on ...

journal_title：Biotechnology and bioengineering

authors： Kim JH,Hosobuchi M,Kishimoto M,Seki T,Yoshida T,Taguchi H,Ryu DD

更新日期：1985-10-01 00:00:00

abstract：:The production of ethanol from carob pod extract by free and immobilized Saccharomyces cerevisiae cells in batch and fed-batch culture was investigated. Fed-batch culture proved to be a better fermentation system for the production of ethanol than batch culture. In fed-batch culture, both free and immobilized S. cerev...

journal_title：Biotechnology and bioengineering

authors： Roukas T

更新日期：1994-02-05 00:00:00

abstract：:The effects ensuing from the interaction between membrane-bound sarcosine dehydrogenase and the surrounding lipids as well as the effects of membrane fluidity were described in this study. A 25-fold activation was observed upon the reconstitution of the enzyme in bilayers of SUVs made of DMPC. The considerable decreas...

journal_title：Biotechnology and bioengineering

authors： Kheirolomoom A,Katoh S,Sada E,Yoshida K

更新日期：1991-04-15 00:00:00

abstract：:Continuous cellulase production by Trichoderma viride QM 9123, immobilized in 6 mm diameter, spherical, stainless steel biomass support particles, has been achieved using a medium containing glucose as the main carbon source. Experiments were carried out in a 10-L spouted bed fermentor. In this type of reactor-recycle...

journal_title：Biotechnology and bioengineering

authors： Webb C,Fukuda H,Atkinson B

更新日期：1986-01-01 00:00:00

abstract：:Hydrogen production by Rhodobacter capsulatus is an anaerobic, photobiological process requiring specific mixing conditions. In this study, an innovative design of a photobioreactor is proposed. The design is based on a plate-type photobioreactor with an interconnected meandering channel to allow culture mixing and H2...

journal_title：Biotechnology and bioengineering

authors： Turon V,Ollivier S,Cwicklinski G,Willison JC,Anxionnaz-Minvielle Z

更新日期：2020-12-15 00:00:00

abstract：:Increased stability at alkaline pH should be a valuable attribute for the utilization of penicillin acylase in bioreactors employed to convert penicillins into 6-aminopenicillanic acid, a precursor of semisynthetic penicillins. In these systems, base is added for pH control, which results in local alkaline conditions ...

journal_title：Biotechnology and bioengineering

authors： Del Río G,Rodríguez ME,Munguía ME,López-Munguí A,Soberón X

更新日期：1995-10-20 00:00:00

abstract：:An algorithm for operating a fed-batch fermentor at an optimum specific fermentation rate is proposed. It does not require on-line measurement of nutrient concentration in the culture medium. An on-line estimate of the specific fermentation rate is sufficient for implementation of this scheme. The algorithm is model i...

journal_title：Biotechnology and bioengineering

authors： Agrawal P,Koshy G,Ramseier M

更新日期：1989-01-05 00:00:00

abstract：:The Ff filamentous bacteriophages show potential as a new class of therapeutics, displaying utility in materials science as well as pharmaceutical applications. These phages are produced by the infection of E. coli, a Gram-negative bacterium which unavoidably sheds endotoxins into the extracellular space during growth...

journal_title：Biotechnology and bioengineering

authors： Branston SD,Wright J,Keshavarz-Moore E

更新日期：2015-08-01 00:00:00

abstract：:This article describes a methodology that implements a Markov decision process (MDP) optimization technique in a real time fed-batch experiment. Biological systems can be better modeled under the stochastic framework and MDP is shown to be a suitable technique for their optimization. A nonlinear input/output model is ...

journal_title：Biotechnology and bioengineering

authors： Saucedo VM,Karim MN

更新日期：1997-07-20 00:00:00

abstract：:Biomanufacturing exhibits inherent variability that can lead to variation in performance attributes and batch failure. To help ensure process consistency and product quality the development of predictive models and integrated control strategies is a promising approach. In this study, a feedback controller was develope...

journal_title：Biotechnology and bioengineering

authors： Schmitt J,Downey B,Beller J,Russell B,Quach A,Lyon D,Curran M,Mulukutla BC,Chu C

更新日期：2019-09-01 00:00:00

abstract：:The results of an initial study of enzymatic catalysis in metastable supersaturated solutions of carbohydrates are presented. It has been shown that such solutions, formed in the presence of small amounts of water and alcohol as plasticizers, are sufficiently stable under ambient conditions to enable enzymatic transfo...

journal_title：Biotechnology and bioengineering

authors： Millqvist-Fureby A,Gill IS,Vulfson EN

更新日期：1998-10-20 00:00:00