384 Biotechnology Chap. 9 is complete and can be released from the ribosome to carry out its function. Some proteins remain in the cytoplasm for cell maintenance and operations. Others are needed in the nucleus; some proteins, such as digestive enzymes, leave the cells for other functions. 9.6.6 Summary The following analogy is somewhat exaggerated but: • The genetic information carried on DNA is analogous to the designer at the tup of Hgure 4.17in Chapter 4. • The mRNA and transcription are analogous to the process planning steps that convert design information to the specific details of manufacturing. • Ribosomes are the sites where proteins are translated or synthesized, and thus analogous to fabrication machinery. • The proteins are the manufactured product. which then do the work of the cells. • These proteins can be seen as the "workers," who bring energy back into the overall system. The created proteins and enzymes subsequently enable other processes, such as "triggering" the promoters, which then make copies of the genes. The whole process, summarized here, thus becomes self-replicating. With the review of both biosciences in Section 9.5 and bioprocesses in Sec- tion 9.6, some aspects of biotechnology and specifically genetic engineering and manufacturing can now be considered in more detail. 9.7 GENETIC ENGINEERING I: OVERVIEW 9.7.1 Motivation and Goals The most common type of genetic engineering in biotech uses recombinant DNA technologies to transfer genetic information from one organism to another for a potentially useful purpose. For example, in agriculture, there is now the possibility of new breeds of plants and animals. In medicine, there is also help for people with genetic diseases. Genes have now been identified that are involved in Huntington's disease, cystic fibrosis, sickle-cell anemia, retinoblastoma, and Alzheimer's disease. Also in medicine, the manufacturing of useful proteins through genetic engi- neering is a basic goal of many biotech firms. There is growing interest in the manu- facture of cytokines (such as interferon), which are important for immune system function. Recombinant DNA technologies can also be used to produce insulin. Diabetic people fail to produce sufficient quantities of the protein insulin and hence are unable to control their sugar metabolism. A daily injection of insulin can regulate their system without interfering directly with the other bodily chemical reactions. In the past, the insulin could be obtained only by expensive extractions from a hog pan- creas. Now, genetic engineering has enabled bacteria to produce a plentiful supply, plus help for patients who were allergic to hog insulin. Injecting natural or synthetic 9.7 Genetic Engineering I:Overview 385 proteins (such as insulin) into an organism can induce temporary changes in the organism's protein content and function. Permanent changes can also be obtained in an organism, if it is possible to manipulate protein synthesis inside its cells. 9.7.2 The Essential Steps Figure 9.15,by Nicholl (1994),provides a "snapshot" of manufacturing by gene cloning. • Step 1: The original DNA of an organism, plant, or animal is first cut into frag- ments. • Step 2: It is then joined to a carrier, called a vehicle or a vector. • Step 3: This recombined DNA is then reintroduced into the cell of a host organism. With the proper manufacturing controls, clones grow. Gene splicing is one of the most routine and fundamental steps in gene cloning and is a mainstay of biotech research activities. It is essentially a cut-and-paste process similar to film splicing, except instead of film stock, pieces of DNA are used, as shown in Figure 9.16. 9.7.3 Step 1: Cutting DNA Using Restriction Enzymes In the first step of Figure 9.15, DNA is cut into fragments at precisely defined nucleotide sites by restriction enzymes. This process is shown in Figure 9.17. (1) t t t DNAfrllgments Introduce into host cell Join to vector 22 s! Flame 9.15 Schematic diagrams of gene cloning. (From An Introduction to Genetic Engineering by Desmond S.T.NichoU, C 1994. Reprinted with the pennistion of Cambridge University Press.) Grow clones 3.6 Biotechnology Chap.9 Figure 9.16 Movie-film splicing as an analogy for gene splicing.Only a short section of II gene is represented, and in fact many nucleotide pairs and movie-film frames would be contained in the two "bracketed" areas on the right of the figure (from Understllnding DNA and Gene Cloning by Drlica, Copyright © 1992. Reprinted by permission of John Wiley & Sons, Inc.}, 9.7.4 Step 2: Joining DNA Using the Enzyme DNA Ligase Once isolated. a DNA fragment is ready to be joined to another DNA molecule. This requires the presence of another enzyme called DNA ligase Thisjoining process is a key aspect of recombinant DNA technology:the DNA ofone organism canbe linked to the DNA of a completely different organism Thisisshowninstep 2 of Figure 9.15and in Figure 9.18. This second DNA molecule is usually a circular plasmid or a phage-short for bacteriophage. These are shown in Figures 9.19 and 9.20. The plasmid or phage is caned a vector. 9.7.5 Step 3: Vectors, Hosts, and Cloning The plasmid or phage vector is used to carry the recombinant DNA into a host cell where the genetic material can be propagated. Host cells are most commonly bac- teria or yeast, single-celled organisms that can exhibit phenomenal growth rates. They are therefore an important tool in cloning. In a manufacturing context, these hosts can be viewed as the "transfer line for mass production." When the host cells with the recombinant DNA divide, they produce a large number of genetically identical clones, as shown in part 3 of Figure 9.15. The most common bacterial host is Escherichia coli. E. coli is in our intestines right now, as well as in those of most animals. (Out of interest, this bacterium gained notoriety in recent years when several people were killed or sickened by undercooked hamburgers that had an excess of E. coli. However, this form of E. coli is different from laboratory strains, which are not pathogenic.) E. coli is the bacteria of choice for gene cloning because it has been so well studied over the last few decades that it is now charac- terized and its functions well understood. E. coli cells-at high magnification-are IGeneticletter (nucleotide pair) 0<", , Scene I Frame Film DNA 9.7 Genetic Engineering I: Overview 387 Q1 DNA Flpft 9.17 CUttingof DNA into short "staggered" pieces.When a restriction enzyme is added to the DNA, it binds to the DNA and cuts it Note there are three cut sites in the top diagram.1bis converts the DNA molecule into four shorter moleeules: a,b,c, and d. Each has "sticky ends" that can subsequently form base pairs with other DNA in the splicing procedures (from Undmt4ndillg DNA and Gene Ckming by Drlica, Copyright C 1992.Reprinted by permission of John Wiley & Sons,Inc.). shown in Figure 9.21;growing bacterial colonies-more or less at life size-are shown in Figure 9.22. 9.7.6 Transgenic Plants and Animals A transgenic plant or animal is one that has been altered to contain a gene from another organism, usually from another species. Genetic manipulation of plants is well established as the science of selective breeding. Direct manipulation of plant genes is a newer but relatively commonplace technique substantially similar to the gene cloning methods for bacteria and yeast. Add restriction endouuclease c- to cut DNA Recognition sequences 388 Biotechnology Chap. 9 DNA ~nCubate fragments to allowjoining [IjDNAligase seaIsnicks- in DNA FIpre 9.18 Joining two DNA fragments. The complementary ends of DNA facilitate the joining process. "Nicks" are enzymatically sealed by DNA ligase (from Understanding DNA and Gene Cloning by Drlica, Copyright © 1992. Reprinted by permission of John Wiley & Sons, Inc.) FIpre 9.l9 An artist's impressions of (a) Circular plasmids and (b) an enlargement of a plasmid showing a short region becoming singlc-atranded, Nick Nick [...]... to stay on top of manufacturing developments in their field and to pursue distance learning/continuing education opportunities in manufacturing processes that have been outsourced Even though the physical manufacturing process may be outsourced, the internal designers must still keep pace with the knowledge in that field In summary, for all firms,the manufacturing process is always a part of a larger... commercial enterprise Future Aspects of Manufacturing 408 Chap 10 10.3 FROM THE PAST TO THE PRESENT 10.3.1 Mass Production and Taylorism Chapter 1 reviewed the history of manufacturing It included some details of the industrial revolution (1780 1820),the importance of interchangeable parts (Colt and Whitney), and organized mass production with a division between design and manufacturing (Taylor and Ford) In... CHAPTER FUTURE ASPECTS OF MANUFACTURING 10.1 RESTATEMENT OF GOALS AND CONTEXT The goals of this book are to: • Illustrate general principles of manufacturing (Chapters 1 and 2) •Review some of the main manufacturing techniques needed during the product development cycle of a consumer electromechanical product (Chap- ters 3 through 8) • Review the emerging market of biotechnology manufacturing (Chapter... Shuler,M L.1992 Bioprocess engineering 2 San Diego, CA; Academic Press in Med- Press animals." Science News 140 (10): 148 The university-industrial complex New Haven; Yale Univer- O'Connor, G M.1995 From new drug discovery to bioprocess operations: nology.IEEE Engineering in Medicine and Biology 14 (2): 2m Rosenfield, Oxford: Engineering In Encyclopedia Press U.S.A of physical science and technology... issues ~olecular biology Molecular targeting Bench-scale synthesis Manufacturing Issues Pilot-scale production Large-scale manufacturing F1IUre 9.27 Critical path for biotech design for planning to large-scale production (Adapted from O'Connor, 1995 © 1995 IEEE Reprinted, with permission, from iEEE Engineering ill Medicine and Biology, vot 14, no 2, p.2rf7,March-ApriI1995.) interest in, the smaller start-up... the resulting DNA sequences into a carrier molecule or vector, and introduce that vector into a host cell so that it propagates and grows 9.11,13 GeneticCode Figure 9 .14 shows the 64 possible codons and the amino acids specified 9.11 .14 Genetic by each Engineering The practice of manipulating genetic information encoded in a DNA fragment to conduct basic research or to generate a medical or scientific... interests, combined with a focus on group-oriented case study projects or consulting projects, requires a certain amount of flexibility and compromise on everyone's part The book and its related lectures are deliberately a survey of each manufacturing topic and also focus on issues in today's business environment This has two obvious limitations: 406 10.2 Management of Technology 407 First, as far as... passed on Over hundreds and thousands of generations, a species may develop a whole set of features that have enhanced its survival in a particular environment Biotechnology 404 Chap 9 9.11.18 Nucleotide A building block for DNA and RNA A nucleotide is composed of three parts: a sugar, a phosphate, and a chemical base In DNA, the bases are adenine (A), guanine (G), thymine (T), and cytosine (C) RNA contains... in a big warehouse is dead For the PC industry in particular, the inventory is flying through the air in the belly of one of FedEx's or DHL's cargo planes or being sorted at the airport hub for next-day delivery (Tanzer, 1999) Overall, what is needed is a cross-functional, interdisciplinary approach that fosters communication and integration among all parts of an enterprise A fundamental prerequisite... is for a firm to become a "learning organization" that constantly examines its production practices for potential improvements (Cole, 1999) In contrast to the compartmentalized mentality of Taylorism, the learning organization reintegrates manufacturing with planning and creativity It promotes integrated problem solving among all groups, including shop floor personnel, production staff, design engineers, . technology developed during genome research, particularly the automation and optimization routines, willgreatly benefit the biotech industry. 9.10.2 Manufacturing Despite these advances in knowledge,. that it propagates and grows. 9.11,13 GeneticCode Figure 9 .14 shows the 64 possible codons and the amino acids specified by each. 9.11 .14 Genetic Engineering The practice of manipulating genetic. fibrosis, sickle-cell anemia, retinoblastoma, and Alzheimer's disease. Also in medicine, the manufacturing of useful proteins through genetic engi- neering is a basic goal of many biotech firms.