File Name: recombinant technology and its application .zip
Recombinant DNA rDNA molecules are DNA molecules formed by laboratory methods of genetic recombination such as molecular cloning that bring together genetic material from multiple sources, creating sequences that would not otherwise be found in the genome.
It is generated by transferring selected pieces of DNA from one organism to another.
Uses of Recombinant DNA in Agriculture
It is generated by transferring selected pieces of DNA from one organism to another. The vial shown in the photograph contains human insulin, one of the first therapeutic proteins that was genetically cloned. The drug is used to treat diabetes. Credit: Wellcome Library, London. Genetic engineering is used for many different purposes in research, medicine, agriculture and industry.
The technology is important because it enables the creation of multiple copies of genes and the insertion of foreign genes into other organisms to give them new traits, such as antibiotic resistance or a new colour. One of the first ways in which the technology was deployed was to re-engineer microbial cells to produce foreign proteins.
This facilitated the manufacture of human proteins on an unprecedented scale at minimum cost, thereby opening the way to study the function of proteins in greater detail and to their therapeutic use. By over 80 recombinant DNA based products had been approved for treating disease and for vaccination and a further recombinant DNA-based drugs were being tested for safety and efficacy.
The technology is also an important tool in agriculture, being used to improve plants' resistance to pests and increase crop yields. While the structure of DNA was first determined in , it was to take another two decades before scientists had the means to generate recombinant DNA. This was aided by firstly the realisation in the s that plasmids, small mobile pieces of DNA, could replicate in huge quantities independently of chromosomal bacteria DNA and that they could transfer genetic information.
It was this process that gave host bacteria the capacity to inherit new genes and therefore new functions such as resistance to antibiotics. Another important tool for creating recombinant DNA was the discovery in the s by the Swiss microbiologist Werner Arber and American biochemist Stuart Linn that bacteria could protect themselves from attack by viruses the production of endonucleases, known as restriction enzymes, which could seek out a single DNA sequence in a virus and cut it precisely in one place.
This process prevented the replication of viruses and hence the death of virally infected bacteria. This was demonstrated by Daniel Nathans to be a useful tool for cutting and pasting specific DNA segments.
In Paul Berg, attached to Stanford University, demonstrated the feasibility of splicing and recombining genes for the first time. Gene cloning has a diverse range of applications.
Where it has proven particularly useful has been in mapping out the human genome, the creation of transgenic animals, and the development of insect-resistant crops. It is also pivotal to genetic tests carried out in forensic science and archaeology as well as in tests for determining hereditary disease and paternity.
The technology also forms the backbone of hepatitis and human immunodeficiency virus HIV diagnostic tests. Recombinant DNA technology has also proven important to the production of vaccines and protein therapies such as human insulin, interferon and human growth hormone. It is also used to produce clotting factors for treating haemophilia and in the development of gene therapy. Janet Mertz forced to halt experiment to clone recombinant DNA in bacteria after safety concerns raised.
Temporary moratorium called for on genetic engineering until measures taken to deal with potential biohazards. Nobel Prize given in recognition of discovery of restriction enzymes and their application to the problems of molecular genetics. University of Edinburgh scientists published the successful isolation and cloning DNA fragments of the hepatitis B virus in Escherichia coli.
Biogen applied for European patent to clone fragment of DNA displaying hepatitis B antigen specificity. First chimeric monoclonal antibodies developed, laying foundation for safer and more effective monoclonal antibody therapeutics. Results released from first small-scale clinical trial of recombinant interferon-alpha therapy for post-transfusion chronic hepatitis B.
FDA approved the use of genetically engineered interferon-alpha, Intron A, for the treatment of hepatitis B. Respond to or comment on this page on our feeds on Facebook , Instagram or Twitter. Facebook Twitter Donate to WiB. He is credited with improving the nucleic acid hybridisation technique. It is now used for analysing the organisation of the genome, studying gene expression and for developing recombinant DNA. This was based on some experiments he performed with Edward Tatum in which involved mixing two different strains of bacteria.
Their experiments also demonstrated for the first time that bacteria reproduced sexually, rather than by cells splitting in two, thereby proving that bacterial genetic systems were similar to those of multicelluar organisms. Later on, in , working with Norton Zinder, Lederberg found that certain bacteriophages viruses that affect bacteria could carry a bacterial gene from one bacterium to another.
In Lederberg shared the Nobel Prize for Medicine for 'discoveries concerning genetic recombination and the organisation of the genetic material of bacteria.
This he did as part of his work to study viral chromosomes. He was awarded the Nobel Prize in for this work. His technique paved the way to the development of genetic engineering and the modern biotechnology industry. Berg was also instrumental in the setting up of the Asimolar Conference on Recombinant DNA, in , which drew up the first guidelines for experiments with genetic engineering.
He was also instrumental in the application of genetic engineering to agricultural plants to improve their output and resistance to pests, salt and drought. His work inspired the use of restriction enzymes for many different biotechnology applications, including DNA sequencing and the construction of recombinant DNA.
He was awarded the Nobel Prize in Physiology or Medicine in for his work on restriction enzymes. He shared the Nobel Prize in for helping to discover restriction enzymes and showing their application in molecular genetics.
It was based on some work he carried out in the s. Arber indicated in that restriction enzymes could be used as a tool for cleaving DNA. The enzymes are now an important tool for genetic engineering. Together with Matthew Medelsohn, Stahl showed that the double-stranded helix molecule of DNA separates into two strands and that each of these strands serve as a template for the production of a new strand of DNA.
They did this in Following this work, Stahl did extensive work on bacteriophages, viruses that infect bacteria, and their genetic recombination. In he established that DNA in T4 bacteriophages is circular rather than linear.
Eight years later he and his wife, Mary, found a DNA sequence in the lambda bacteriophage necessary to initiate genetic recombination.
This laid the foundation for genetic engineering. This he achieved with Kent Wilcox in Smith was awarded the Nobel Prize for Physiology or Medicine in for his part in the discovery of the enzyme. It was the first bacterial genome to be deciphered. Later on he helped in the genomic sequencing efforts for the fruit fly and humans at Celera Genomics.
In he found a way to make Escherichia coli acquire a plasmid that made it resistant to the antibiotic tetracycline. He also discovered with Herbert Boyer a restriction enzyme that could cleave a circular plasmid at a single site.
This laid the foundation for their joint experiment in which demonstrated the feasibility of combining and replicating genetic information from different species. Their experiment involved inserted a gene for frog ribosomal RNA into bacterial cells which then expressed the gene.
Three patents were taken out on their technique. These paved the way to the rise of new start-up biotechnology companies, founded on the back of the promise of genetic engineering for generating new therapeutic products.
This they did by combining a gene for frog ribosomal RNA with a bacterial plasmid which was then put into a strain of E-coli for expression. Based on this technique Boyer helped found Genentech, the first biotechnology company dedicated to commercialising recombinant DNA.
This he did in in collaboration with Robert Swanson. He also spearheaded efforts for the scientific governance of recombinant DNA and genome editing technologies. From to Swanson was Chief Executive and Director of the company and played an instrumental role in leading it to become the first major biotechnology company to show a profit and go public.
It has the advantage that it can be easily grown in E Coli and is not pathogenic except in the case of bacteria. Lederberg's discovery paved the way to understanding the transfer of genetic material between bacteria, the mechanisms involved in gene regulation and how piece of DNA break apart and recombine to make new genes. He published his experiment in the Journal of Biological Chemsitry in May Louis Werner Arber, Swiss microbiologist and geneticist, and his doctoral student Daisy Dussoix proposed that bacteria produce restriction and modification enzymes to counter invading viruses.
Arber, 'Host-controlled modification of bacteriophage', Annual Review Microbiology, 19 , They found that bacteria protect themselves against invading viruses by producing two types of enzymes. One cut up the DNA of the virus and the other restricted its growth. Arber believed these two enzymes could provide an important tool for cutting and pasting DNA, the method now used in genetic engineering.
Its discovery was pivotal to the development of recombinant DNA. The two scientists announced their achievement to a press conference as part of an effort to increase the American public's appreciation of government funded scientific work. It, however, generated debate about whether life should be created in a test tube. The achievement was an important stepping stone to the development of recombinant DNA.
Restriction enzymes are now workhorses of molecular biology. They are essential in the development of recombinant DNA and were pivotal to the foundation of the biotechnology industry. The enzyme was simultaneously discovered independently by Howard Temin and David Baltimore. Temin made the discovery while working on Rous sacoma virions and Baltimore was working on the poliovirus and vesicular stomatis virus. The discovery laid the foundations for the the disciplines of retrovirology and cancer biology and ability to produce recombinant DNA.
Following this Berg self-imposed a moratorium on experiments in his laboratory involving the cloning of SV40 in E-Coli. The session was chaired by Norton Zinder. The discussion set the stage for the subsequent Asilomar Conference in which led to the first guideline for experiments with genetic engineering.
It was generated by cutting DNA with a restriction and then using ligase to paste together two DNA strands to form a hybrid circular molecule. They managed to splice sections of viral DNA and bacterial DNA with the same restriction enzyme to create a plasmid with dual antibiotic resistance.
The technique showed it was possible to reproduce recombinant DNA in bacteria. It argued for the establishment of an advisory committee to oversee experimental procedures to evaluate the potential biological hazards of recombinant DNA molecules and develop procedures to minimise the spread of such molecules within human and other populations. In addition to the moratorium the conference established several principles for safely conducting any genetic engineering.
Containment was considered essential to any experimental design, such as the use of hoods, and the use of biological barriers was suggested to limit the spread of recombinant DNA. This included using bacterial hosts that could not survive in natural environment and the use of vectors plasmids, bacteriophages and other viruses that could only grow in specified hosts. The conference also called for a moratorium on genetic engineering research in order to have time to estimate the biohazard risks of recombinant DNA research and develop guidelines.
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Recombinant DNA changes the natural genetic makeup and the characteristics of an organism by inserting DNA from another organism. Also known as genetic engineering, recombinant DNA technology is widely used in agriculture to create genetically-modified organisms that produce genetically-modified crops. The first GM food was the Flavr Savr tomato, produced in , which had a longer shelf life and an enhanced flavor. Since then, the number of GMOs has exploded as producers prefer them over traditional crops because they yield more and require less care. Some GMO crops are resistant to herbicides. Introduction of a herbicide-resistant bacterial gene into plant DNA makes the plant resistant to that herbicide. Genetically-modified soybeans, corn, cotton, potatoes and wheat resist herbicides sprayed on farms to kill weeds.
Not a MyNAP member yet? Register for a free account to start saving and receiving special member only perks. Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. There is no evidence that unique hazards exist either in the use of R-ONA techniques or in the movement of genes between unrelated organisms. To avoid inhibiting the development and. A classification scheme must rest on lems that have resulted from the extensive reliance on considerations of several types, including the nature of the chemicals in both agriculture and industry. R-ONA techniques constitute a powerful and safe new means for the modification of organisms.
Recombinant DNA , molecules of DNA from two different species that are inserted into a host organism to produce new genetic combinations that are of value to science , medicine , agriculture, and industry. Since the focus of all genetics is the gene , the fundamental goal of laboratory geneticists is to isolate, characterize, and manipulate genes. Although it is relatively easy to isolate a sample of DNA from a collection of cells , finding a specific gene within this DNA sample can be compared to finding a needle in a haystack. Consider the fact that each human cell contains approximately 2 metres 6 feet of DNA. Therefore, a small tissue sample will contain many kilometres of DNA.
Authors : Alemayehu Choramo and Motuma Debelo. Abstract: Human beings want enjoying highest attainable standard of basic health without discrimination of race, religion and political belief, economic or social condition. The benefits of medical, psychological and related knowledge have to be extended all people to the fullest attainment of health. Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity. Three factors affect human life greatly by: deficiency of food, health problems and environmental issues.
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The first production of recombinant DNA molecules, using restriction enzymes, occurred in the early s. Researchers at UC San Francisco and Stanford used restriction enzymes to cut DNA from different species at specific sites, and then fused the cut strands from the different species back together. Boyer would co-found Genentech, Inc. Paul Berg, a biochemist at Stanford who was among the first to produce a recombinant DNA molecule in , wrote a letter shortly afterwards, along with ten other researchers, to the journal Science. In the letter, they urged the National Institutes of Health to regulate the use of recombinant DNA technology and meanwhile, they urged scientists to halt most recombinant DNA experiments until they better understood whether the technique is safe.
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