For each phase the author identifies decision rules that provide for successful corporate growth. The book begins with discussions of the evolution of biotechnology; entrepreneurship in the biotechnology industry; university-industry technology transfer process; and the life cycle of a biotechnology company.
It considers the prospects for biotechnology, from the perspective of a venture capitalist and human resource practitioner. There are separate chapters that deal with the cloning and expression of recombinant gene products; developing strategies to reduce the cost-to-produce CTP therapeutic proteins; intellectual property protection; and the regulation of commercial biotechnology. The final chapters cover the marketing of biotechnology companies and products; the performance of biotechnology stocks; mergers and acquisitions in the biotechnology industry, and prospects for the Japanese and European biotechnology industry.
I was very fortunate to work for the company that begat the biotech industry during its formative years. This experience established a solid foundation from which I could grow in both the science and business of biotechnology. After my fourth year of working on Oyster Point Boulevard, a close friend and colleague left Genentech to join a start-up biotechnology company.
Later, he approached me to leave and join him in of all places — Oklahoma. He persisted for at least a year before I seriously considered his proposal. After listening to their plans, the opportunity suddenly became more and more intriguing. Finally, I took the plunge and joined this ent- preneurial team in cofounding and growing a start-up biotechnology company. Making that fateful decision to leave the security of a larger company was extremely difficult, but it turned out to be the beginning of an entrepreneurial career that forever changed how I viewed the biotechnology industry.
Since that time, I have been fortunate to have cofounded two other biotechnology com- nies and even participated in taking one of them public. During my career in these start-ups, I held a variety of positions, from directing the science, operations, regulatory, and marketing components, to subsequently becoming CEO.
For all the resources on how to start companies and on how to manage established companies in other sectors, there is a dearth of material on unique and critical issues in starting biotechnology companies, as well as managing the transition from start-up to established company. It is to this gap that Biotechnology Entrepreneurship is directed. This accessible introduction to common laboratory techniques focuses on the basics, helping even readers with good math skills to practice the most frequently encountered types of problems.
Discusses very common laboratory problems, all applied to real situations. Explores multiple strategies for solving problems for a better understanding of the underlying math.
Basic Industrial Biotechnology Author : S. Basic Laboratory Calculations for Biotechnology, Second Edition discusses very common laboratory problems, all applied to real situations. It explores multiple strategies for solving problems for a better understanding of the underlying math. Primarily organized around laboratory applications, the book begins with more general topics and moves into more specific biotechnology laboratory techniques at the end.
This book features hundreds of practice problems, all with solutions and many with boxed, complete explanations; plus hundreds of "story problems" relating to real situations in the lab. Additional features include: Discusses common laboratory problems with all material applied to real situations Presents multiple strategies for solving problems help students to better understand the underlying math Provides hundreds of practice problems and their solutions Enables students to complete the material in a self-paced course structure with little teacher assistance Includes hundreds of "story problems"that relate to real situations encountered in the laboratory.
The book provides state-of-the-art and integrative views of translational biotechnology by covering topics from basic concepts to novel methodologies. Topics discussed include biotechnology-based therapeutics, pathway and target discovery, biological therapeutic modalities, translational bioinformatics, and system and synthetic biology.
Additional sections cover drug discovery, precision medicine and the socioeconomic impact of translational biotechnology. This book is valuable for bioinformaticians, biotechnologists, and members of the biomedical field who are interested in learning more about this promising field.
Explains biotechnology in a different light by using an application-oriented approach Discusses practical approaches in the development of precision medicine tools, systems and dynamical medicine approaches Promotes research in the field of biotechnology that is translational in nature, cost-effective and readily available to the community.
This book contains almost multiple choice questions as well as fill in the blanks with answers covering all aspects of molecular biological systems of prokaryotes and eukaryotes. In writing the first edition, the aim is to provide all simple and difficult questions for weak students in plant molecular biology that have no more knowledge and have more problems in solving the questions.
Biotechnology Author : David P. Using straightforward, less-technical jargon, Clark and Pazdernik introduce each chapter with basic concepts that develop into more specific and detailed applications.
This up-to-date text covers a wide realm of topics including forensics, bioethics, and nanobiotechnology using colorful illustrations and concise applications.
In addition, the book integrates recent, relevant primary research articles for each chapter, which are presented on an accompanying website. The articles demonstrate key concepts or applications of the concepts presented in the chapter, which allows the reader to see how the foundational knowledge in this textbook bridges into primary research.
Thus, biotechnology is not a sudden discovery but rather a com- ing of age of a technology that was initiated several decades ago. If it is accepted that biotechnology has its roots in distant history and has large, successful industrial outlets, why then has there been such increased public awareness of this subject in recent years?
Undoubtedly, the main dominating reason must derive from the rapid advances in molecular biol- ogy, in particular recombinant DNA technology, which are giving humans dominance over nature. While in theory the technology is available to transfer a particular gene from any organism into any other organism, microorganism, plant or animal, in actual practice there are numerous constraining factors, such as which genes are to be cloned and how they can be selected.
The developments of biotechnology are proceeding at a speed simi- lar to that of microelectronics in the mid-ls.
Although the analogy is tempting, any expectations that biotechnology will develop commercially at the same spectacular rate should be tempered with considerable caution. New biotechnology will have a con- siderable impact across all industrial uses of the life sciences.
The growth in awareness of modern biotechnology parallels the serious worldwide changes in the economic climate arising from the escalation of oil prices since l There is a growing realisation that fossil fuels although at present in a production glut period and other non-renewable resources will one day be in limited supply.
Countries with climatic conditions suit- able for rapid biomass production could well have major economic advan- tages over less climatically suitable parts of the world. In particular, the tropics must hold high future potential in this respect. Another contributory factor to the growing interest in biotechnology has been the current recession in the Western world, in particular the depression of the chemical and engineering sections, in part due to the increased energy costs.
Biotechnology has been considered as one impor- tant means of restimulating the economy, whether on a local, regional, national or even global basis, using new biotechnological methods and new raw materials. In part, the industrial boom of the l—ls was due to cheap oil; while the information technology advances in the ls and ls resulted from developments in microelectronics.
There is undoubtedly a worldwide increase in molecular biological research, the formation of new biotechnological companies, large invest- ments by nations, companies and individuals, and the rapid expansion of databases, information sources and, above all, extensive media coverage.
Indeed, many of the innovations in biotechnology will not appear a priori as new products, but rather as improvements to organisms and processes in long-established biotechnological industries, e.
New applications are likely to be seen earliest in the areas of healthcare and medicine, followed by agriculture and food technology. Exciting new medical treatments and drugs based on biotechnology are appearing with ever-increasing regularity. Prior to l, insulin for diabetics was derived from beef and pork pancreases. The gene for human insulin was then isolated and cloned into microorganisms that were then mass-produced by fermentation.
In clinical diagnosis there are now hundreds of specialised kits available for simple home use or for complex laboratory procedures, such as blood screening. Over the past decade the generation of biopharmaceutical products has greatly expanded both in numbers and types of products approved by the US Food and Drug Administration FDA ; in there were 39 products and by there were well over a hundred on the market.
Similarly, there has been a wide adoption of transgenic crops, with world acreage increasing from about 4 million acres in to over million acres in just over ten years. Increasingly, biotechnology will evolve as a powerful and versatile approach that can compete with chemical and physical techniques of reduc- ing energy and material consumption and minimising the generation of waste and emissions.
Biotechnology will be a valuable, indeed essential, contribution for achieving industrial sustainability in the future. There is an ever-increasing diversity and scale of raw material consumption and this means that it is becoming urgent to act to minimise the increasing pressures on the environment.
Applications in chemical production, fuel and energy production, pollution control and resource recovery will pos- sibly take longer to develop and will depend on changes in the relative economics of currently employed technologies. The use of biotechnology with respect to the environment could have contrasting effects. On the one hand there would be many posi- tive effects on environmental conservation, e. Figure 1. Biotechnology-based industries will not be labour intensive, and although they will create valuable new employment the need will be more for brains than muscle.
Much of modern biotechnology has been devel- oped and utilised by large companies and corporations. Must manage regulatory authorities, public perception; issues of health and safety; risk assessment.
Business climate characterised by rapid change and considerable risk — one biotechnology innovation may quickly supersede another. Biotechnology business growth highly dependent on venture capital — usually needs exceptionally high level of funding before profit sales return. Knowledge of biotechnology innovations must be translated through to all sectors of industry. Many new, high-technology biotech companies have arisen from entrepreneurs from academia who are often dominant, charismatic indi- viduals whose primary aim has been to develop a new technology.
New biotechnology companies have certain features not often seen in others Table 1. The position of new biotechnology at the interface between academia and industry creates a unique need for abstracting information from a wide range of sources, and companies spend large sums on infor- mation management.
Biotechnology is high-technology par excellence. Translating research into application is neither easy nor inevitable and requires a unique investigator and also a unique environment. Truly, new biotechnology has come of age. For biotechnology to be commercially successful and exploited there is a need both to recruit a specialist workforce and also for the tech- nology to be understood and applied by practitioners in a wide range of other areas including law, patents, medicine, agriculture, engineer- ing, etc.
Also many already employed in biotechnology-based industries must regularly have means of updating their knowledge or even retraining. Such programmes are designed not only for the needs of students but also for company training activities and are written in the user-friendly style of good, open-learning materials. The currency of biotechnology throughout the world will be an educated, skilled workforce with ready access to the ever-widening knowledge and resource base.
In the majority of examples developed to date, the most effective, sta- ble and convenient form for the catalyst for a biotechnological process is a whole organism, and it is for this reason that so much of biotechnol- ogy revolves around microbial processes. This does not exclude the use of higher organisms; in particular, plant and animal cell culture will play an increasingly important role in biotechnology.
Furthermore, microorganisms can possess extremely rapid growth rates far in excess of any of the higher organisms such as plants and animals. Thus immense quantities can be produced under the right environmental conditions in short time periods. These new techniques have largely arisen from fundamental achievements in molec- ular biology over the last two decades.
These manipulated and improved organisms must be maintained in substantially unchanged form and this involves another spectrum of tech- niques for the preservation of organisms, for retaining essential features during industrial processes and, above all, retaining long-term vigour and viability.
The second part of the core of biotechnology encompasses all aspects of the containment system or bioreactor within which the catalysts must func- tion Fig. Here the combined specialist knowledge of the bioscientist and bioprocess engineer will interact, providing the design and instrumen- tation for the maintenance and control of the physico-chemical environ- ment, such as temperature, aeration, pH, etc.
Having achieved the required endpoint of the biotechnological process within the bioreactor, e. Processing will usually involve more than one stage. Downstream processing costs as approximate proportions of selling prices of fermen- tation products vary considerably, e.
Successful involvement in a biotechnological process must draw heavily upon more than one of the input disciplines. The main areas of application of biotechnology are shown in Table 1. Novel fermenter designs to optimise productivity. Enzyme technology Used for the catalysis of extremely specific chemical reactions; immobilisation of enzymes; to create specific molecular converters bioreactors.
Products formed include L-amino acids, high fructose syrup, semi-synthetic penicillins, starch and cellulose hydrolysis, etc. Enzyme probes for bioassays. Waste technology Long historical importance but more emphasis is now being placed on coupling these processes with the conservation and recycling of resources; foods and fertilizers, biological fuels.
Environmental technology Great scope exists for the application of biotechnological concepts for solving many environmental problems pollution control, removing toxic wastes ; recovery of metals from mining wastes and low-grade ores.
Renewable resources technology The use of renewable energy sources, in particular lignocellulose, to generate new sources of chemical raw materials and energy — ethanol, methane and hydrogen. Total utilisation of plant and animal material. Clean technology, sustainable technology. Plant and animal agriculture Genetically engineered plants to improve nutrition, disease resistance, maintain quality, and improve yields and stress tolerance will become increasingly commercially available.
Improved productivity etc. Improved food quality, flavour, taste and microbial safety. Healthcare New drugs and better treatment for delivering medicines to diseased parts. Improved disease diagnosis, understanding of the human genome — genomics and proteomics, information technology.
Biotechnology offers a great deal of hope for solving many of the problems that the world faces! In practice, such barriers come from the costs of testing products to meet regulatory standards, possible delays and uncer- tainties in regulatory approval, and even outright disapproval of new prod- ucts on grounds of safety.
Concern has been expressed in the USA that over-zealous and perhaps unrealistic regulatory requirements are damaging the future industrial development of some areas of biotechnology and, consequently, they are systematically reassessing their regulatory requirements. The use of recombinant DNA technology has created the greatest areas of possible safety concern. Public attitudes to biotechnology are most often related to matters of perceived or imaginary dangers in the techniques of genetic manipulation.
The implementation of the new techniques will be dependent upon their acceptance by consumers. Associated with genetic manipulation are diverse questions of safety, ethics and welfare. Public understanding of these new technologies could well has- ten public acceptance. Consequently, it is conceivable and indeed the case that a small number of activists might argue the case against genetic engi- neering in such emotive and ill-reasoned ways that both the public and the politicians are misled.
The biotechnology community needs to sit up and take notice of, and work with, the public. Most compa- nies, however, neglected certain essential marketing questions such as, who will be buying the new products and what do these people need to under- stand?
What biotechnology needs with the public is dialogue! In the developed world agricultural sciences are well developed producing an abundance of high-quality products. Worldwide there will be enough food for all, but will it always continue to be disproportionately distributed?
Sadly, there is a growing gap between biotechnology in highly industrialised countries and the biotechnology-based needs of developing countries. The ability of developing nations to avail themselves of the many promises of new biotechnology will to a large extent depend on their capac- ity to integrate modern developments of biotechnology within their own research and innovation systems, in accordance with their own needs and priorities.
The United Nations Millenium Development Goal for has targeted poverty alleviation, improved education and health, together with environ- mental sustainability. The main areas of biotechnology that can contribute to these aims are listed in Table 1. In the following chapters some of the most important areas of biotechnology are considered with a view to achieving a broad overall understanding of the existing achievements and future aims of this new area of technology.
Biotechnology is just now entering this golden period. A spectacular future lies ahead. Chapter 2 Biomass: a biotechnology substrate? Many traditional agricultural products may well be further exploited with the increasing awareness of biotechnology. Biomass agriculture, aquaculture and forestry may hold great economic potential for many national economies particularly in tropical and subtrop- ical regions Fig.
Indeed, the development of biotechnological processes in developing areas where plant growth excels could well bring about a change in the balance of economic power. It should be noted that the non-renewable energy and petrochemical feedstocks on which modern society is so dependent oil, gas and coal were derived from ancient types of biomass. Modern industrialised nations have come to rely heavily on fossil reserves for both energy and as feedstocks for a wide range of production processes.
In little over a century the industri- alised world has drawn heavily on fossil fuels that took millions of years to form beneath the beds of the oceans or in the depths of the earth. Further- more, it is a very unequal pattern of usage. Table 2. The answer to these problems must be the use of photosyn- thetically derived biomass for energy and industrial feedstocks.
Currently more than ten times more energy is generated annually by photosynthe- sis than is consumed by mankind. At present, large-scale exploitation of biomass for fuel and chemical feedstocks is restricted by the cost of fossil alternatives, the heterogeneous nature of biomass sources and their diffuse distribution. The use of biomass directly as a source of energy has long been practised in the less industrialised nations such as Latin America, China, India and Africa.
In developed nations, biomass derived from agriculture and forestry has largely been directed to industrial and food uses Table 2. At present biomass is used to derive many products of industrial and commercial importance Table 2. These are mainly carbohydrates of varying chemical complexity, and include sugar, starch, cellulose, hemicellulose and lignin.
The wide range of by- products obtained from raw materials that are of use in biotechnological processes is shown in Table 2.
Sugar-bearing raw materials such as sugar beet, sugar cane and sugar millet are the most suitable and available to serve as feedstocks for biotech- nological processing. Many tropical economies would collapse if the markets for sugar were to be removed. Already cane sugar serves as the substrate for the Brazilian gasohol programme, and many other nations are rapidly seeing the immense potential of these new technologies.
A slight disadvantage of starch is that it must usually be degraded to monosaccharides or oligosaccharides by digestion or hydrolysis before fermentation. However, many biotechnolog- ical processes using starch are being developed, including fuel production. There can be little doubt that cellulose, both from agriculture and forestry sources, must contribute a major source of feedstock for biotech- nological processes such as fuels and chemicals.
However, cellulose is a very complex chemical and invariably occurs in nature in close association with lignin. The ability of lignocellulose complexes to withstand the biodegrada- tive forces of nature is witnessed by the longevity of trees, which are mainly composed of lignocellulose.
Lignocellulose is the most abundant and renewable natural resource available to man throughout the world. At present, expensive energy-demanding pre-treatment processes are required to open up this complex structure to wide micro- bial degradation. Pure cellulose can be degraded by chemical or enzymatic hydrolysis to soluble sugars, which can be fermented to form ethanol, butanol, acetone, single cell protein SCP , methane and many other prod- ucts. It has been realistically calculated that approximately 3.
On a worldwide basis land plants produce 24 tonnes of cellulose per person per year. Time will surely show that lignocellulose will be the most useful carbon source for biotechnological developments. Agricul- tural and forestry wastes come in many diverse types: cereal straws, corn husks and cobs, soy wastes, coconut shells, rice husks, coffee bean husks, wheat bran, sugar cane bagasse and forestry wastes including trimmings, sawdust, bark, etc.
Only a modest fraction of these wastes is utilised on a large scale due primarily to economic and logistical factors. A primary objective of biotechnology is to improve the management and utilisation of the vast volumes of agricultural, industrial and domestic waste organic materials to be found throughout the world. The biotechno- logical utilisation of these wastes will eliminate a source of pollution, in particular water pollution, and convert some of these wastes into useful by-products.
Not all processes will involve biosystems. Reverse osmosis is a method of concentrating liquid solutions in which a porous membrane allows water to pass through but not the salts dissolved in it.
Waste materials are frequently important for economic and environ- mental reasons. For example, many by-products of the food industry are of low economic value and are often discharged into waterways, creating serious environmental pollution problems. An attractive feature of carbo- hydrate waste as a raw material is that, if its low cost can be coupled with suitable low handling costs, an economic process may be obtained.
However, the composition or dilu- tion of the waste may be so dispersed that transport to a production centre may be prohibitive. On these occasions biotechnology may only serve to reduce a pollution hazard. Each waste material must be assessed for its suitability for biotechno- logical processing. Only when a waste is available in large quantities and preferably over a prolonged period of time can a suitable method of utili- sation be considered Table 2. Upgrade the food-waste quality to make it suitable for human consumption.
Feed the food waste directly or after processing to poultry, pigs, fish or other single-stomach animals that can utilise it directly. Feed the food waste to cattle, or other ruminants, if unsuitable for single-stomach animals because of high fibre content, toxins or other reasons.
Production of biogas methane and other fermentation products if unsuitable for feeding without expensive pre-treatments. Selective other purposes such as direct use as fuel, building materials, chemical extraction, etc. Initial separation of non-starch components may be required Lignocellulosic materials Corn cobs, oat hulls, straw, bagasse, wood Normally requires complex pre-treatment wastes, sulphite liquor, paper wastes involving reduction in particle size followed by various chemical or enzymic hydrolyses.
Energy intensive and costly acids and commercial yeasts for baking, and is directly used in animal feed- ing. Whey, obtained during the production of cheese, could also become a major fermentation feedstock. More complex wastes such as straw and bagasse are widely available and will be increasingly used as improved processes for lignocellulose break- down become available Table 2.
However, where intensive animal rearing is undertaken, serious pollution problems do arise. Future biotechnological processes will increasingly make use of organic materials that are renewable in nature or occur as low-value wastes that may presently cause environmental pollution.
In the s there was a worldwide glut of chemical and petrochemical feedstocks and alternative uses were being actively pursued.
At this time also there was concern that there would be a worldwide shortage of protein. The energy companies producing these excess feedstocks were then drawn into the concept of using them as fermentation substrates to produce bacte- rial protein — single-cell protein or SCP.
While massive fermentation programmes were initiated and operated in the developed nations e. Europe, USA and Russia full commercialisation was never achieved, due in part to the change in oil prices in the s and to the lack of appearance of a worldwide protein shortage. However, escalating oil prices in the ls created profound reappraisals of these processes, and as the price of crude oil approached that of some major cereal products there was a reawakening of interest in many fermentation processes for the production of ethanol and related products.
However, the decrease in oil prices in l again widened the gap and left uncertainty in the minds of industrial planners. However, once again, oil prices have escalated and it is doubtful if they will ever again decrease. The most important criteria that will determine the selection of a raw material for a biotechnological process will include price, availability, com- position, form and oxidation state of the carbon source.
At present the most widely used and of commercial value are corn starch, molasses and raw sugar. There is little doubt that cereal crops, particularly maize, rice and wheat, will be the main short- and medium-term raw materials for biotech- nological processes. It is hoped that this can be achieved without seri- ously disturbing human and animal food supplies.
Throughout the world there is an uneven distribution of cereal production capacity and demand. Although much attention has been given to the uses of wastes in biotechnology there are many major obstacles to be overcome. For instance, availability of agricultural wastes is seasonal and geographical availabil- ity problematic; they are also often dilute and may contain toxic wastes.
However, their build-up in the environment can present serious pollu- tion problems and therefore their utilisation in biotechnological processes, albeit at little economic gain, can have overall community value. Biotechnology will have profound effects on agriculture and forestry by enabling production costs to be decreased, quality and consistency of products to be increased, and novel products generated.
Wood is extensively harvested to provide fuel, materials for construc- tion and to supply pulp for paper manufacture. There may also be an increased non-food use of many agriculturally derived substances such as sugars, starches, oils and fats.
Supplies in excess of food needs could allow new industries to develop and reduce poverty. Devel- opment of disease-resistant cotton plants by new molecular methods could have major economical and environmental impact.
How successful will biomass be as a crucial raw material for biotechnol- ogy? Chapter 3 Genetics and biotechnology 3. There are two broad categories of genes — structural and regulatory. Struc- tural genes encode for amino acid sequences of proteins, which, as enzymes, determine the biochemical capabilities of the organism by catalysing par- ticular synthetic or catabolic reactions or, alternatively, play more static roles as components of cellular structures. In contrast, the regulatory genes control the expression of the structural genes by determining the rate of production of their protein products in response to intra- or extracellular signals.
The derivation of these principles has been achieved using well known genetic techniques, which will not be considered further here. The seminal studies of Watson and Crick and others in the early s led to the construction of the double-helix model depicting the molecular structure of DNA, and subsequent hypotheses on its implications for the understanding of gene replication. Since then there has been a spectacu- lar unravelling of the complex interactions required to express the coded chemical information of the DNA molecule into cellular and organismal expression.
Changes in the DNA molecule making up the genetic comple- ment of an organism are the means by which organisms evolve and adapt themselves to new environments. The precise role of DNA is to act as a reser- voir of genetic information. In nature, changes in the DNA of an organism can occur in two ways: 1 by mutation, which is a chemical deletion or addition of one or more of the chemical parts of the DNA molecule 2 by the interchange of genetic information or DNA between like organ- isms normally by sexual reproduction, and by horizontal transfer in bacteria.
In eukaryotes, sexual reproduction is achieved by a process of conju- gation in which there is a donor, called male, and a recipient, called female. Often these are determined physiologically and not morphologi- cally. Bacterial conjugation involves the transfer of DNA from a donor to a recipient cell. Transduction is the transfer of DNA mediated by a bacte- rial virus bacteriophage or phage and cells that have received transducing DNA are referred to as transductants. Genetic trans- fer by this way in bacteria is a natural characteristic of a wide variety of bacterial genera such a Campylobacter, Neisseria and Streptomyces.
Strains of bacteria not naturally transformable can be induced to take up isolated DNA by chemical treatment or by electroporation. Classical genetics was, until recently, the only way in which heredity could be studied and manipulated. However, in recent years, new tech- niques have permitted unprecedented alterations in the genetic make-up of organisms even allowing exchange in the laboratory of DNA between unlike organisms.
Organismal manipulation Genetic manipulation of whole organisms has been happening naturally by sexual reproduction since the beginning of time. The evolutionary progress of almost all living creatures has involved active interaction between their genomes and the environment. Active control of sexual reproduction has been practised in agriculture for decades — even centuries. In more recent times it has been used with several industrial microorganisms, e.
It involves selection, mutation, sexual crosses, hybridisation, etc. However, it is a very random process and can take a long time to achieve desired results — if at all in some cases.
Cellular manipulation Cellular manipulations of DNA have been used for over two decades, and involve either cell fusion or the culture of cells and the regeneration of whole plants from these cells. Successful biotechnological examples of these methods include monoclonal antibodies see later and the cloning of many important plant species. This is the much publicised area of genetic engineering or recombinant DNA technol- ogy, which is now bringing dramatic changes to biotechnology.
Current industrial ventures are concerned with the production of new types of organism, and of numerous compounds ranging from phar- maceuticals to commodity chemicals; these are discussed in more detail in later chapters. The success of strain selection and improvement programmes practised by all biologically based industries e.
The task of improving yields of some primary metabolites and macromolecules e. Advances have been achieved in this area by using screening and selection techniques to obtain better organisms.
In a selection system all rare or novel strains grow while the rest do not; in a screening system all strains grow, but cer- tain strains or cultures are chosen because they show the desired qualities required by the industry in question.
How- ever, such methods normally lead only to the loss of undesired character- istics or increased production due to loss of control functions. It has rarely led to the appearance of a new function or property. Thus, an organism with a desired feature will be selected from the natural environment, prop- agated and subjected to a mutational programme, then screened to select the best progeny.
In particular, this has been the case in antibiotic-producing microorganisms; this has meant that the only way to change the genome with a view to enhancing produc- tivity has been to indulge in massive mutational programmes followed by screening and selection to detect the new variants that might arise. Once a high-producing strain has been found, great care is required in maintaining the strain.
Strain or culture instability is a constant problem in industrial utilisation of microorganisms and mammalian cells. Industry has always placed great emphasis on strain viability and productivity potential of the preserved biological material. Most industrially important microorganisms can be stored for long periods, for example in liquid nitrogen, by lyophili- sation freeze-drying or under oil, and still retain their desired biological properties.
However, despite elaborate preservation and propagation methods, a strain has generally to be grown in a large production bioreactor in which the chances of genetic changes through spontaneous mutation and selec- tion are very high.
The chance of a high rate of spontaneous mutation is probably greater when the industrial strains in use have resulted from many years of mutagen treatment. Great secrecy surrounds the use of indus- trial microorganisms and immense care is taken to ensure that they do not unwittingly pass to outside agencies. There is now a growing movement away from the extreme empiricism that characterised the early days of the fermentation industries.
Fundamen- tal studies of the genetics of microorganisms now provide a background of knowledge for the experimental solution of industrial problems, and increasingly contribute to progress in industrial strain selection.
In recent years, industrial genetics has come to depend increasingly on two new ways of manipulating DNA — protoplast and cell fusion, and recombinant DNA technology. These are now important additions to the technical repertoire of the geneticists involved with biotechnological indus- tries.
A brief examination of these techniques will attempt to show their increasingly indispensable relevance to modern biotechnology. Immediately within the cell wall is the living membrane, or plasma membrane, retaining all the cellular components such as nuclei, mitochon- dria, vesicles, etc. For some years now it has been possible, using special techniques in particular, hydrolytic enzymes , to remove the cell wall, releasing spherical membrane-bound structures known as protoplasts.
These protoplasts are extremely fragile but can be maintained in isolation for vari- able periods of time. In practice, it is the cell wall that largely hinders the sexual conjugation of unlike organisms. Only with completely sexually compatible strains does the wall degenerate allowing protoplasmic interchange. Thus natural sexual-mating barriers in microorganisms may, in part, be due to cell wall limitations, and by removing this cell wall, the likelihood of cellular fusions may increase.
Protoplasts from different strains can sometimes be persuaded to fuse and so overcome the natural sexual-mating barriers. However, the range of protoplast fusions is severely limited by the need for DNA compatibility between the strains concerned.
Fusion of proto- plasts can be enhanced by treatment with the chemical polyethylene glycol, which, under optimum conditions, can lead to extremely high frequencies of recombinant formation that can be increased still further by ultraviolet irradiation of the parental protoplast preparations.
Protoplast fusion can also occur with human or animal cell types. Protoplast fusion has obvious empirical applications in yield improve- ment of antibiotics by combining yield-enhancing mutations from different strains or even species. Protoplasts will also be an important part of genetic engineering, in facilitating recombinant DNA transfer.
Fusion may provide a method of re-assorting whole groups of genes between different strains of macro- and microorganisms. One of the most exciting and commercially rewarding areas of biotech- nology involves a form of mammalian cell fusion leading to the formation of monoclonal antibodies. It has long been recognised that certain cells B-lymphocytes within the bodies of vertebrates have the ability to secrete antibodies that can inactivate contaminating or foreign molecules the antigen within the animal system.
It has been calculated that a mammalian species can generate up to million different antibodies thereby ensuring that most invading foreign antigens will be bound by some antibody. For the mammalian system they are the major defence against disease-causing organisms and other toxic molecules.
It is now known that individual B-lymphocyte cells produce single antibody types. However, in George Kohler and Cesar Milstein successfully demonstrated the production of pure or monoclonal antibodies from the fusion product hybridoma of B-lymphocytes antibody- producing cells and myeloma tumour cells.
Stage 3: the Survive in special medium specific antibody-producing STAGE 2 hybridoma is selected and propagated in culture vessels in Cloned on agar and selected vitro or in animal in vivo and monoclonal antibodies harvested. Single hybrid cells can then be selected and grown as clones or pure cultures of the hybridomas.
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