Enzymes

In recent years, enzymes have gained wider applications in the biotechnology industry. The global industrial market has recently been valued at 1.4 billion, with an expected market increase of 4-5 (99). Enzymes are grouped into six major classes oxidoreductases, transferases, hydrolases, lyases, ligases, and isomerases. The majority of commercialized enzymes are hydrolases such as amylase, cel-lulase, xylanases, pectinase, proteases, lipase, and collagenase. Other important enzymes are glucose...

Alkaline dpeptidase

D-Aminopeptidase (EC 3.4.11.19) from Ochrobactrum an-thropi was discovered, and its primary structure has been found to have similarity to the -lactamases and penicillin-binding proteins (21,28). The enzyme acts mostly on pep-tides with D-Ala at the N-terminus to yield D-amino acids it does not act on D-amino acid derivatives with bulkier substituents. We proposed that D-aminopeptidase is a new penicillin-recognizing enzyme (11) based on its primary structure, inhibition by -lactam compounds,...

Effects of Ammonia on Product Expression

Because ammonia affects cell growth and metabolism, it is conceivable that it also affects the product expression. Either directly or indirectly, ammonia can affect the product concentration obtained in the culture and thus the process efficiency. The indirect effect of ammonia on production results from the reduced cell growth rate and subsequent cell density achieved in the culture. Even though the specific productivity may not have been altered, the cell density and longevity of the culture...

Conclusion

Animal cell lines are an established tool in biotechnology and will be used extensively in a variety ofemerging areas, such as tissue engineering, organ replacement, or drug discovery. A vast amount of knowledge and experience has accumulated concerning the cell lines described in this article, and research into improved industrial large-scale use is still on going. Safety concerns using continuous cell lines with a tumorigenic potential are addressed frequently. As a result of numerous efforts...

Affinity Constant of Electron Donor Ks

The constant Ks is an affinity constant in the substrate-uptake kinetics. It is known that reported Ks values can vary over a wide range (10 3 to 10 6 mol L). Even for the same organism, for example, E. coli, many different Ks values are found (30). Much of this wide spread is probably due to systematic errors in the determination of the Ks parameter. These errors can be due to ill-defined conditions of the microorganisms (adaptation), statistically unsound procedures to evaluate Ks from...

Hs

Where G k1 aRT gH is the dimensionless mass transfer coefficient F YS'mlzXym is the dimensionless product inhibition factor X gnJkebRT is the maximum possible viable cell concentration in the biophase and S'm is the product concentration that completely inhibits cell growth. Rather than solving equations 2 and 4 exactly, which would require the form of the inherent kinetic function q(S, Sm), consider some limiting cases in order of decreasing liquid outflow rate. These cases are used to...

Effects of Ammonia on Cell Metabolism

A number of studies reported the effects of ammonia on cell metabolism. For a murine hybridoma cell line, Ozturk et al. (6) observed a roughly twofold increase in glucose and glutamine consumption rates in cultures exposed to 3.75 mM of ammonia, compared to control conditions (Fig. 3). The production rates of lactate and ammonia were also enhanced by the presence of ammonia, indicating an elevated metabolic state of the cells. The yield coefficients of ammonia from glutamine and lactate yield...

AbR gene E coli

Single-crossover recombination showing integration of an intact integration vector into the host chromosome at the site of the target gene. Part or all of the target gene is duplicated as a result of the integration event. The inclusion of a controllable promoter upstream of the target gene fragment on the vector allows for controllable gene expression of the 3' copy of the gene or any genes downstream in the same operon. AlP, selectable antibiotic resistance gene. than 4,100...

What Is the Purpose of ASTM

As stated in the ASTM Technical Committee Officer Handbook (1), the charter purpose is the development of standards on characteristics and performance of materials, products, systems and services and the promotion of related knowledge. Currently, ASTM has 132 standards-writing technical committees, publishes more than 9,000 standards annually, and has more than 35,000 technically qualified members who voluntarily develop and maintain current standards in their committee specialty (2). The more...

Combination of Thermostability Related Mutations

To produce multiple mutants with combinations of two or three thermostability-related amino acid mutations, restriction fragments containing the mutations were used to replace the corresponding mutation-free DNA fragments (16). In the DCase of Agrobacterium sp. KNK712, the mutation of the 57th amino acid is located in a Ndel-SacI DNA fragment of about 190 bp the 203rd amino acid mutation is in a SaK-Clal DNA fragment of about 170 bp (hereinafter this fragment is referred to as fragment A) and...

PCR and Related Methods

DNA and RNA hybridization tests have been developed to detect organisms whose specific gene sequence of interest is known. At first, radioactive compounds were used to re port the hybridization, but recently, the reaction has been reported by enzyme and color reactions. The truly revolutionary development in genetic type of identification of microorganisms is in the field of PCR technology. In this technology, the gene sequence of the organism of interest (an anaerobe, for example) is known at...

Cell Accumulation

Where a is the recycle ratio equal to the recycle volume divided by the feed volume, C is the concentration factor cell concentration in the recycle divided by the effluent concentration related to the efficiency of the separation step, and X0, X1, and X2 are the cell concentrations in the feed, recycle, and separator effluent streams, respectively. Note that the low substrate concentrations in waste treatment create suboptimal growth environments in which cell death cannot be neglected....

Characteristics And Potential Of Fluidizedbed Bioreactors

The use of fluidized-bed bioreactors can provide a number of advantages that makes them an interesting alternative for bioprocesses, especially for continuous operation. In comparison with conventional mechanically stirred bio-reactors, fluidized-bed bioreactors provide a much lower attrition of solid particles, and almost any kind of immobilized biocatalyst preparation can be used without physical disruption. Biocatalyst concentration can be significantly higher because of immobilization, and...

Airlift Reactor Morphology

Airlift reactors can be divided into two main types of reactors on the basis of their structure Fig. 1 1 external-loop vessels, in which circulation takes place through separate and distinct conduits and 2 baffled or internal-loop vessels, in which baffles placed strategically in a single vessel create the channels required for the circulation. The designs of both types can be modified further, leading to variations in the fluid dynamics, in the extent of bubble disengagement from the fluid,...

Info

Effect of dilution rate on steady-state parameters for C. glutamicum B-6 S- 2-aminoethyl -l-cysteiner rifampicinr, streptomycin1, 6-azauracilr. Culture conditions 5-L jar fermenter, molasses medium, pH 7.0, 32 C, 600 rpm, air at 3 L min, working volume of 2.5 L. Stable l-lysine production for over 300 h. Feeding sugar concentration 12 O, 20 , 28 . Source Ref. 23. L-Lysine HCl is demanded in large quantities for animal feed and must be available at low cost. Reduction of cost through...

Airlift Reactorselection And Design Scaleup of Airlift Bioreactors

The problems encountered in the scale-up of bioreactors can be concentrated into two groups. The first includes the cases in which a high power input per unit volume is used on a laboratory scale, but cannot be maintained on an industrial scale due to economic or mechanical limitations. This is not the case for plant or animal cultures, for which a very high specific power input cannot be used because of cell fragility. The second group of problems can be generalized as lack of knowledge about...

Threedimensional Culture Systems

Animal cell lines have to be classified according to their ability to grow in suspension or be anchorage-dependent. For the large-scale production of biologicals, suspension cells are clearly the substrate of choice. With the development of microcarriers initiated by van Wezel 1967 72 , it is now possible to culture attached cells in bioreactors very similar to suspension cells. Growth of animal cells on microcarriers or immobilized systems facilitates production processes and allows high yield...

Organic Acids

Citric acid is the most important acid produced by fungi and the only organic acid produced almost exclusively through fermentation. Widely used in the food and beverage industry, its pleasant acid taste enhances products such as soft drinks, fruit juices, jams, jellies, candies, prepared desserts, and frozen fruits. Citrates are also efficient buffering and chelating agents and are used by the cosmetics industry and in blood transfusion products, effervescent tablets, detergent manufacturing,...

I I I I I I I I I

Concentration Profiles in Different Bioreactors. a , b Partial pressure in gas phase, dot-dash line c , d Viable biomass concentration, dot-dash line. Dotted line, partial pressure in biophase HS solid line, mole fraction in gas phase. Figure 3. Concentration Profiles in Different Bioreactors. a , b Partial pressure in gas phase, dot-dash line c , d Viable biomass concentration, dot-dash line. Dotted line, partial pressure in biophase HS solid line, mole fraction in gas phase....

Stability of the Immobilized Enzyme

For repeated batch reactions with the immobilized DCase, a substrate solution 3 of c-D-HPG pH 7.0 was prepared, with nitrogen gas bubbling at 40 C. The DCase immobilized on Duolite A-568 and the prepared substrate Figure 7. Construction profile of pNT4553. solution were stirred at 40 C under a stream of nitrogen gas while the pH was controlled at pH 7.0 with 2 M HCl. Samples were taken for activity measurement at 10 and 60 min, the reaction being continued for 23.5 h in total. The reaction...

Dissociation Constant

Amino acids exit aqueous solutions as dipolar ions zwitterions , and glutamic acid may be represented as follows 16 . Following Bronsted, an acid may be defined as a substance capable of combining with a proton. When an amino acid is titrated with HCl and NaOH, a curve exhibiting two points of inflection is obtained. Thus amino acid can react either as an acid or as a base, that is, as an ampholyte. The dissociation constants for glutamic acid are pK1 2.19 COOH , pK2 4.25 COOH , and pK3 9.67...

Solvents

Solvents are compounds that are essentially neutral in character and comprise organic alcohols and ketones. The major solvent products of microbial carbohydrate catabo-lism include ethanol, acetone, isopropanol, butanol, ace-toin, 1,3-propanediol, and butanediol. These are the most useful oxychemicals produced by fermentation. Solvents have various uses in the chemical industry, including the direct use as organic chemicals and indirect use as fuel additives, extenders, or feedstocks for...

Growth

The majority of Bacillus species will grow at mesophilic temperatures on commercially prepared nutrient media, although in some cases it is necessary to modify the pH or salt concentration. Obligate thermophilic species such as B. stearothermophilus that do not grow satisfactorily at 37 C are usually grown at 60 C. Moderately thermophilic species, such as B. coagulans, are grown between 45 C and 50 C. The more fastidious insect pathogens, B. larvae and B. popilliae, require the addition of...

Identification of Apoptosis

Apoptosis Diagram

The search for simple techniques that allow for the identification of apoptotic cells has attracted a considerable Figure 1. Schematic diagram showing the morphological features of apoptotic and necrotic cell death. The cell shown at stage 1 of necrosis exhibits clear swelling and dilation of mitochondria and Golgi. At this stage, nuclear morphology remains unchanged. By stage 2 of necrosis, disruption of organelles and plasma membrane is apparent, nuclear morphology is altered, and complete...

Thermodynamically Based Method To Estimate Growth Stoichiometry

In the previous paragraphs the methods for accurate measurement of a growth stoichiometric coefficient, as, for example, the biomass yield on electron donor FDX and the subsequent calculation of all the nonmeasured stoichio-metric coefficients of the macrochemical equation using the conservation principles have been provided. In past decades, the value of FDX for many different microorganisms, different electron donors, C sources, and electron acceptors has been measured under C- and...

Bibliography

Vargo, in A.S. Lubiniecki and S.A. Vargo eds., Regulatory Practice for Biopharmaceutical Production, Wiley-Liss, New York, 1994, pp. 1-12. 2. J.L. Goergen, I. Chevalot, A. Visvikis, T. Oster, K. Hess, J.M. Engasser, and A. Marc, in R.E. Spier, J.B. Griffiths, and C. MacDonald eds., Animal Cell Technology Developments, Processes and Products, European Society for Animal Cell Technology, Butterworth-Heinemann, Oxford, U.K., 1992, pp. 593595. 3. M.J. Keen and N.T....

Waste Treatment

Microorganisms excel in using organic substances as sources of nutrients and energy. The challenge of wastewater treatment is to remove 1 compounds with a high biochemical oxygen demand, 2 pathogenic organisms and viruses, and 3 a multitude of human-made chemicals. Anaerobic digestion AD is commonly used to treat materials with a high content of insoluble organic matter, such as cellulose, and to degrade concentrated industrial wastes, such as those from the food-processing...

Roll Tubes

One of the most widely used anaerobic cultivation systems is the Hungate roll tube, developed by Hungate 46-48 . Sterile tubes were flushed with CO2 while the medium was aseptically added to the tubes to prevent air contamination. The tubes were then inoculated, sealed with rubber stoppers, cooled 48 C , and hand spun so that the agar with cultures forms a thin film in the inner wall of the test tube. After incubation the colonies could be examined with ease. Isolation of colonies was also...

Advantages of Aspartame Production by Protease

The structures of APM and its regioisomer are shown in Figure 1. In APM production by conventional organic synthesis, the side-chain carboxylic group S-carboxylic group of aspartic acid must be protected to avoid the formation of unwanted -APM additionally, optically pure substrates are required to avoid the production of stereoisomers of APM. These APM-related compounds, such as -APM and stereoisomers, exhibit a bitter taste 1 . Use of a protease as catalyst does not give formation of these...

Mixed Cultures

Mixed cultures are used extensively in food fermentations and in biodegradation of complex substances. Mutualism, commensalism, amensalism, competition, and prey-predator relationships are the main interactions observed in mixed cultures 16 . Mutualism occurs when both species benefit from the interaction, whereas commensalism describes processes where only one species benefits and the other is not affected. Amensalism occurs when one species restricts another, whereas competition affects both...

Immobilized Thermolysin

Immobilization of thermolysin was also expected to reduce enzyme inactivation because it is protected from autolysis. However, an application of immobilized thermolysin in the current production process seems difficult, because the reaction for Z-APM production takes place in the presence of a dense solid precipitate, that is, an insoluble addition compound of Z-APM and PheOMe. If both the immobilized enzyme and the reaction product occur in the reaction mixture as solids, they cannot be...

Fed Batch Fermentation

Fed Batch Fermentation Penicillin

Fed-batch fermentation types are classified in Table 2. This fermentation method is aimed at efficiently carrying out fermentation and is characterized by a low concentration of components in the initial medium to minimize metabolic regulation. At the time of inoculation the medium promotes initial growth of microbes subsequent supplies of more raw materials drive the desirable increase in metabolite biosynthesis. Feeding is effected either intermittently or continuously. Industrial...

Outline

Introduction Metabolism Microbial Production Fermentation Method Chemical Properties Dissociation Constant Racemization Properties of L-Glutamic Acid salt Formation Infrared spectra Ionic Forms L-Glutamic Acid Hydrochloride Sodium Salt of L-Glutamic Acid Crystal Structure L-Glutamic Acid Monosodium Salt Pentahydrate Calcium Salt of L-Glutamic Acid Industrial Production Extraction Method Industrial Fermentation Method Separation Process Crystallization of L-Glutamic Acid Pyramid Type...

Stereospecific Reduction of Ethyl 4Chloroacetoacetate

Ethyl R -4-chloro-3-hydroxybutanoate formed through the reduction of ethyl 4-chloroacetoacetate with cells of S. salmonicolor showed low optical purity 8.5 ee because the cells contained a significant amount of an enzyme s catalyzing the reduction of ethyl 4-chloroacetoacetate to ethyl S -4-chloro-3-hydroxybutanoate in addition to the aldehyde reductase forming ethyl R -4-chloro-3-hydroxy-butanoate. Because heat treatment and acetone fraction-ation of a cell-free extract of S. salmonicolor...

Biological Membrane Fragments

A novel method using biological materials to achieve an-aerobiosis was developed by Adler and Crow 26 . Sterile suspensions of membrane fragments derived from Esche-richia coli were able to remove oxygen rapidly and efficiently as a result of the presence of a cytochrome-based electron transport system that transfers hydrogen from suitable donors in the bacteriological media to oxygen and produces water as an end product. The membranes are stable, nontoxic, and active in both liquid and solid...

Introduction

Activated carbon is a predominantly amorphous solid that has an extraordinarily large internal surface area and pore volume. These unique characteristics are responsible for its adsorptive properties, which are exploited in many different liquid- and gas-phase applications. Activated carbon is an exceptionally versatile adsorbent because the size and distribution of the pores within the carbon matrix can be controlled to meet the needs of current and emerging markets 1 . Engineering...

Mixed Bacterium and Yeast Interaction

Yeast is one of the most important organisms for industrial use in alcoholic fermentation. Bacterial contamination may occasionally occur during yeast fermentation, which may pose serious problems for the fermentation industry. This section deals with the interaction of Saccharomyces cerevisiae with Acetobacter suboxydans or E. coli in mixed-culture growth. S. cerevisiae was grown in mixed cultures with either A. suboxydans or E. coli in a culture medium and glucose at 28 C. Growth was...

Industrialscale Applications

Expanded-bed adsorption is a technique with great potential for initial purification. The number of published industrial scale applications is limited because until recently columns and adsorbents suitable for use in expanded beds were not available. In addition to the three industrial-scale applications described below, an IND Investigational New Drug application has been filed with the Food and Drug Administration for a therapeutic recombinant protein in which expanded-bed adsorption is...

Inorganic Matrices

A large selection of inorganic matrices are commercially available for incorporating homogenous catalysts, and some have been applied to chromatography separations. These matrices include silica, alumina, glass, zeolite, clay, celite, zerconia, titania, magnesium oxide, and carbon. Only a limited number of these matrices with suitable pore structure, particle size, and mechanical stability can be used for chromatography separation of biomolecules. Silica, alumina, and glass are available with a...

Oo

This does not have a C O group, but instead intermediate Figure 3. IR spectra of l-glutamic acid- related substances. Figure 3. IR spectra of l-glutamic acid- related substances. some between C O and C O. The spectra of the amino acids at the isoelectric point of pH do not show the existence of C O, which indicates that the COOH group is ionized. In a similar way, the ionization of the NH2 is indicated. The optical rotation changes with changing pH in solution at 25 C glutamic acid a D G H2O is...

Genetic Manipulation

A wide range of genetic techniques has been developed for B. subtilis, making it among the most amenable bacteria to genetic manipulation. These techniques include classical in vitro and in vivo mutagenic methods and extremely efficient in vitro genome manipulation methods that are in advance of those available for other bacteria, including Escherichia coli 18 . Bacillus vectors have been designed to allow recombinant or mutant genes to be maintained autonomously in the host or integrated into...

Taxonomy

Aspergillus Tetrazonus

The filamentous fungi that comprise the genus Aspergillus reproduce mitotically through the production of spores borne on a specialized structure called the conidiophore. The morphology of this spore-bearing structure, with its distinctive foot cell, long stalk, swollen apex, and protuberant phialides, is the defining feature of the genus. It was first described in 1729 by Micheli, an Italian priest, who was reminded of a Roman Catholic device used to sprinkle holy water, the aspergillum. All...

Future Prospects

The study of apoptosis from an animal-cell-technology standpoint is still in its infancy. However, even at this early stage, significant progress has been made, and it would appear that suppression of apoptosis can lead to improvements in culture viability and, indeed, productivity. It is now necessary to study the prevalence of apoptosis in other culture systems, and then to examine the effect of the suppression of bcl-2 overexpression on cell survival. Studies of a variety of high-density...

X

Strategy allowed an integration of the cell separation step with ion exchange adsorption of the gene product with simultaneous volume reduction, which resulted in a highly condensed but still efficient recovery process 55 . The two-step purification process, ion exchange chromatography in an expanded-bed format followed by IgG affinity chroma-tography for polishing, demonstrated an overall yield of more than 90 . An alternative strategy to simplify downstream processing was investigated by...

Amino Acid Production Monosodium Glutamate

Corynebacterium glutamicum, which produces L-gluta-mate, requires biotin for growth but excessively forms L-glutamic acid at a biotin concentration suboptimal for growth. Under the condition of excess biotin, L-glutamic acid can be produced by 1 adding penicillin 19 or a surface-active agent 20 , or 2 culturing an oleic acid-requiring strain at growth-limiting oleic acid concentrations 20,21 . Cane molasses, beet molasses, and corn syrup are mainly used as the carbon source because of their low...

Effects of Temperature and pH on Enzyme Stability

To evaluate the thermostability of the DCases, a cell-free extract 100 uL was incubated at various temperatures 55-85 C for 10 min, the denatured protein was removed by centrifugation, and then the residual activity was measured by the standard HPLC method. The heat denatur-ation profiles of the four mutant enzymes from KNK402M, KNK404M, KNK416M, and KNK455M and the native enzyme were investigated. The relative activities in comparison with the activities of the non-heat-treated enzymes were...

Apoptosis And Animal Cell Biotechnology

At present, there are around 100 new biopharmaceuticals in phase I, II, and III clinical trials 79 . Production of a biologically active therapeutic will, in many cases, necessitate expression of the protein in mammalian cell lines. As a result of intense commercial pressure, tried and tested production processes are often adopted in order to ensure that the product reaches the market in the shortest possible time. Initially, such production processes were relatively inefficient and there was...

Effect of Ammonia on Product Quality

Ammonia was reported to affect the conditions in intra-cellular compartments and enzymatic reactions for protein processing. High ammonia concentrations were reported to alter protein after translations, glycosylation, and secretion. Ammonia can alter the intracellular or intracom-partmental pH, alter membrane potentials, and directly interact with enzymes. Thorens and Vassalli 98 reported inhibition of sialic acid transferase for Immunoglobulin Ig M at 10 mM ammonia. The results indicate a pH...

[5 kDa

Schematic presentation of staphylococcal protein A SpA and streptococcal protein G SpG . a The complete SpA gene product and the 7-kDa B-domain analog Z, represented in the most widely used divalent form. b The SpG gene product, with the separate albumin- and immunoglobulin-binding regions indicated, and a presentation of some of the most commonly used albumin-binding affinity tags. BB 25 kDa was the first isolated serum albumin-binding affinity tag 14 . More recently, the new tags...

Mycotoxins

Filamentous fungal metabolites that cause human or veterinary diseases are called mycotoxins. The mycotoxins that have received the most attention are the aflatoxins, a family of highly toxic, mutagenic, and carcinogenic compounds produced by certain strains of A. flavus, Aspergillus nomius, and A. parasiticus. These species regularly contaminate peanuts, corn, cottonseed, rice, tree nuts, and other agricultural commodities 28 . A large body of epi-demiological and molecular biological data...

Aspartame Production by Thermolysin

The principles of the thermolysin process were introduced by Oyama et al. 9 in 1987. At first, L-PheOMe from racemic PheOMe is coupled with Z-Asp stereo and regio selectively by thermolysin. The reaction product, Z-APM, forms an insoluble addition compound with one molecule of remaining D-PheOMe immediately and precipitates. When the reaction is completed, the Z-APM-D-PheOMe addition compound is collected as a solid product, and ther-molysin is recovered from the solution. D-PheOMe is separated...

Problematic Antibodies

As has been seen, antibodies can be remarkably diverse. One problem seen is when an antibody does not behave in a fashion similar to others of the same isotype. The solution of this type of problem is just good old-fashioned process optimization. A much more serious problem is the purification of an antibody with limited solubility. A wide variety of additives can potentially be used for solubilization of antibodies, including urea, guanidine HCl, detergents, and sugars. Needless to say, there...

Ultrafiltration

As already mentioned, there are several biological and engineering disadvantages that need to be solved in conventional production methods. To overcome these disadvantages, we have developed a novel bioreactor process, the membrane reactor system, using microbial cells without artificial immobilization for the enzymatic reaction. Co-ryneform bacterium MJ-233, which is employed in this process, is characterized by nonlytic properties under non-growing conditions. The cost of the enzyme is low...

Generation of Ammonia Caused by Glutamine Degradation

Glutamine is not stable in aqueous solutions and is degraded to yield a five-member ring structure, pyrrolidone carboxylic acid, and ammonia 18-20 Glutamine r Pyrrolidone carboxylic acid NH 1 This reaction is irreversible, and the extent of the reaction is affected by the chemical environment of the medium. Glutamine degradation follows first-order kinetics, the half-life of glutamine is reported to be between 6 and 20 days, depending on the conditions 16,21-23 . Glutamine degradation is pH...

Anaerobiosis Tube Systems

Ogg et al. 54 designed a tube with double wells so that agar with cultures can be introduced into the tube and form a thin film. Anaerobiosis is initially achieved by boiling and autoclaving of the medium. By the action of reducing agent in the medium and minimum reabsorption of O2 due to the design of the tube commercially called the Lee tube , good anaerobiosis is maintained in the system. The glass cylinder forming the inner wall the inverted smaller tube makes it easy for enumeration and...

Baby Hamster Kidney Cells

The attached BHK 21 cell line was derived from five un-sexed 1-day-old Syrian hamster Mesocricetus auratus kidneys in 1961. BHK 21 clone 13 was obtained after single-cell isolation and is now widely used, very often only addressed as BHK or BHK 21. Several variants have been developed that are being adapted to suspension culture or suitable for genetic engineering techniques. Because of their susceptibility to various viruses, they have been extensively used for the production of vaccines....

Extraction Method

From 1909, when MSG production started, until 1965, when the extraction process ended, wheat gluten and defatted soybeans were used as the main raw materials, containing as much as 15 to 25 L-glutamaic acid. Crude raw materials were hydrolyzed by heating with hydrochloric acid. After concentration under reduced pressure, the hy-drolyzate was cooled to crystallize L-glutamic acid hydrochloride. L-Glutamic acid can be easily separated from other amino acids in the form of its hydrochloride...

Drosophila Metallothionein Expression System In the

Drosophila Mt. system, the inducible Mt. promotor is used to control the expression of recombinant proteins. This system offers the benefit of a well-known host and genomic structure with a tightly regulated promotor. In contrast to the viral system BEVS, where the production peak is found when the cells already die from the viral infection, Dro-sophila cells and the Mt. expression system can be used continuously. Despite the different expression systems for insect cell lines, development of...

Mixed Bacteria and Mold Interaction

Another example of mixed culture interaction is ensilage of crops. Dalamacio and Fung 35 and Dalmacio et al. 36 studied the influence of ammonia on bacteria and mold during ensilage of high-moisture corn. Bacteria were not affected by ammonia treatment as much as mold at the onset of the treatment. Bacterial populations remained detectable after treatment of 1.0, 1.5, and 2 ammonia. However, no mold was detected for corn treated with 1.0, 1.5, 2.0 ammonia. Corn treated with 0.5 ammonia had high...

Commercial Diagnostic Kits

Gram Positive Egg Shaped Cell

Around the beginning of 1970s with the advancement of miniaturized microbiological techniques and concepts de- Figure 1. Morphology of Clostridium perfringens under 1,000X light-phase-contrast microscopy. This is a gram-positive, rod-shaped, anaerobic, spore-forming bacterium that causes large numbers of foodborne outbreaks and cases in the world. The dark rod-shaped cells are vegetative bacteria, and the bright refractile oval objects are spores developed in the vegetative cells. Figure 1....

Product monosodium Lglutamate

Recovery process flow of monosodium l-glutamate. trolling the pH to neutrality with liquid ammonia. Molasses is fed until L-glutamic acid is no longer produced in the broth. The final L-glutamic acid concentration is around 95 g L. Figure 8 shows a typical fermentation profile in a commercial plant. The method of penicillin addition provides remarkably high productivity of this amino acid compared with fermentation under suboptimal biotin conditions. For purification of L-glutamic...

Industrially Important Strains And Products

Many products are or have been produced by fermentation in commercial quantities 2-4 . Food products, industrial bulk chemicals, solvents, enzymes, and amino acids are produced with the help of anaerobic microorganisms. In this work, the emphasis is on those processes carried out by anaerobes, which generally means that important pathways yield useful products under conditions where oxygen is not required. However, oxygen is present in modest quantities to enhance microbial growth in some...

Anaerobic Glove Boxes

To eliminate the chance of exposure of anaerobes to the natural environment during bacteriological manipulation, the anaerobic chamber, or glove box, was developed. The basic principles for achieving anaerobiosis in the glove box and for promoting binding of residual O2 and H2 in the presence of a catalyst Laidlaw principle are to remove air first and then flush the chamber with inert gas. Reducing agents in the medium also help to reduce the Eh to a desired low level. Companies marketing...

Nadh

Methanogenesis Wastewater

Ferredoxin flavodoxin Ferredoxin flavodoxin Ferredoxin flavodoxin Ferredoxin flavodoxin C. paraputrificum C. bifermentans C. thermohydrosulfuricum C. pasteurianum C. tyrobutyricum may include acetate- and H2-CO2-consuming methano-gens. Anaerobic microorganisms in general show a high degree of metabolic specialization. The success of the anaerobic digestion process therefore depends upon cooperative interactions between microorganisms with different metabolic capabilities. Figure 2 illustrates...

Growth And Product Formation

Anaerobic growth and product formation are often investigated together when the product is growth associated. In anaerobic fermentations, adenosine triphosphate ATP needed for growth is often formed as a result of substrate phosphorylation. Products such as ethanol are produced because the organism is growing and needs ATP for synthesis of microbial cell mass. Mass balances and yield parameters that describe growth and product formation can be written in terms of the mass of substrate, biomass,...

Intracellular pH

Decrease And Increase Intracellular

A possible explanation for the effect of ammonia is simply the alteration of intracellular and intracompartmental pH 6,72,106,107 . Ammonia in cell culture is present in both gaseous and ionic form, and these species are in equilibrium at a ratio determined by the medium pH. At normal pH values, almost all the ammonia present is in the form of ammonium ion, and the concentration of gaseous ammonia is very low pAa 9.2 . The regulation of intracellular cytosolic and intracom-partmental pH in...

Effects of Ammonia on Cell Growth

Although ammonia inhibited cell growth in all these studies, the sensitivity of the growth rate to ammonia concentration varied among the cell lines used. The extent of ammonia inhibition seems to be more severe for primary cells, whereas transformed cells tolerate higher ammonia levels. For 3T3 cells, ammonia levels as low as 0.6 mM reduced cell growth by 60 . However, when the cells are transformed, the reduction was reduced to 15 64 . Addition of 2 mM ammonia reduced growth by 30 for BSC-1...

Removal of Ammonia

Membrane Removal Ammonia

Several techniques were investigated to remove ammonia during cell culture and to improve culture performance. These techniques involve the use of adsorbents, gas exchange and ion exchange membranes, and electrodialysis. Although the systems can be placed in the bioreactor, they are normally used as a loop system Fig. 9 . Cell culture fluid is recycled through a column, where ammonia is removed. In the case of adsorbents, the recycle is halted routinely to allow the regeneration of the column....

Gasphase Applications

Gas-phase applications of activated carbon include separation, gas storage, and catalysis. Although only 20 of activated carbon production is used for gas-phase applications, these products are generally more expensive than liquid-phase carbons and account for about 40 of the total dollar value of shipments. Most of the activated carbon used in gas-phase applications is granular or shaped. Activated carbon use by application is shown in Table 6 74 . Separation processes comprise the main...

Minimization of Ammonia Generation

Glutamine Synthetase Gene Cmv

As mentioned before, ammonia is generated mainly by the spontaneous degradation and cellular metabolism of glu-tamine. Ammonia generation can be minimized by controlling these processes. Minimization of Glutamine Degradation. As previously mentioned, the glutamine degradation rate is dependent on several factors, and it can be minimized by several strategies. Temperature is the most obvious factor, and the media should be kept cold when stored. In the reactor, however, the temperature cannot be...

Factory Fermentation Operation

Fermentation Cooling Flow Diagram

Figures 1 and 6, respectively, show a process flow diagram of amino acid fermentation. The process comprises the steps of laboratory seed culture, factory seed culture Fig. 6 , and fermentation Fig. 1 , and the size of culturing is scaled up in this order. Laboratory Seed Culture and Factory Seed Culture The most important feature in the steps of laboratory and factory seed culture is to ensure active microbes. This promotes initial growth of microbes at the fermentation step and stabilizes...

Blood Plasma Fractionation

The well-known Cohn fractionation process, originally developed in the 1940s to isolate albumin as a blood volume expander during World War II, relies primarily on a series of ethanol fractionation steps to separate the various proteins of human blood plasma from one another according to their solubility behavior in the presence of ethanol 25 . As the role of other plasma components became recognized, such as factors VIII and IX for the treatment of clotting disorders and IgG for use in passive...

Contributors

Abu-Absi, University of Minnesota, St. Paul, Minnesota, Cell Cycle, Eukaryotes Luis A. Actis, Miami University, Oxford, Ohio, Plasmid DNA Replication Michael W.W. Adams, University of Georgia, Athens, Georgia, Enzymes, Extremely Thermostable P.S. Adams, Trudeau Institute, Saranac Lake, New York, Professional Societies, Association of Biomolecular Resource Facilities William R. Adams, Merck Manufacturing Division, West Point, Pennsylvania, Adsorption, Protein, Batch Eduardo Agosin,...

Economic Aspects

Activated Carbon Production From Wood

Excluding eastern European countries and China, where production figures have not been published, the world pro Figure 2. Chemical activation of wood. Figure 2. Chemical activation of wood. duction capacity of activated carbon was estimated to be 375,000 metric tons in 1990 35 . The price of most products was 0.70 to 5.50 kg, but some specialty carbons were more expensive 36, pp. 731.2001P, 731.2001Q . Forty percent of the production capacity was in the United States, 30 in western Europe, 20...

G

Normal water disinfection and filtration treatment steps remove or destroy the bulk of these materials 65 . However, treatment by activated carbon is an important additional step in many plants to remove toxic and other organic materials 66-68 for safety and palatability. Concern over contaminated groundwater sources increased in the 1980s, and in 1984 an Office of Groundwater Protection was created by the EPA 36pp.731.2000V-731.2001L . This led to an increase in...

Merck and Co Inc Rahway New Jersey

New York Chichester Weinheim Brisbane Singapore Toronto This book is printed on acid-free paper. Copyright 1999 by John Wiley amp Sons, Inc. All rights reserved. Published simultaneously in Canada. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the...

Thermal Activation Processes

Thermal activation occurs in two stages thermal decomposition or carbonization of the precursor and controlled gasification or activation of the crude char. During carbonization, elements such as hydrogen and oxygen are eliminated from the precursor to produce a carbon skeleton possessing a latent pore structure. During gasification, the char is exposed to an oxidizing atmosphere that greatly increases the pore volume and surface area of the product through elimination of volatile pyrolysis...