Microorganisms including bacteria, fungi, algae and viruses are important tools used for a wide variety of pharmaceutical and/or biotechnological processes including but not limited to drug and vaccine production, single cell protein production, production of probiotics and other therapeutic, cosmetic or pharmaceutical products. For effective and sustainable production of useful microbial by-products, microorganisms can be genetically engineered or manipulated in order to ensure improved production of quality products in large amounts. The manipulation of microorganisms at the genetic or molecular level simply involves altering the genetic makeup of the microbe in question. Such manipulation usually includes processes that modify the organisms DNA in order to get an improved microbial strain for effective and sustainable production of useful microbial by-products or metabolites. As aforementioned, microorganisms are manipulated for several medical, pharmaceutical, agricultural and commercial purposes; and this manipulation is usually carried out using advanced molecular techniques including molecular cloning of genes.
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Microorganisms are also applied in several bioremediation activities which help to clean up the environment especially in oil spillage areas. More so, microbes can also be genetically engineered and used to manage waste disposal including sewage and other industrial or domestic wastes that are harmful to man, the environment, plants and animals. The genetic manipulation of microbes including bacteria, fungi and viruses offers several ways of engineering microorganisms in such a way that novel strains with the capacity to perform a handful of activities beneficial to man and his environment are developed. Some of these novel strains are used to solve many societal and/or environmental problems including but not limited to pest control, bioremediation, biodegradation, enhanced crop production, improved pharmaceutical, cosmetic and therapeutic productions and degradation of wastes using genetically engineered microbes. The DNA of an organism is manipulated via a process known as genetic engineering.
Genetic engineering is defined as the process of manipulating the genetic makeup of an organism. It is the modification of an organism’s genetic composition by artificial means. Genetic engineering usually involves the transfer of specific traits, or genes, from one organism into a plant or animal of an entirely different species. Genetic engineering encompasses those recent biotechnological technologies used to change the genetic makeup of living cells. Some of these techniques include molecular cloning, electroporation, transformation, transfection and conjugation. Transformation, electroporation, transfection and conjugation are examples of molecular biology tools or gene transfer methods that are used to deliver selected gene(s) into desired organisms or living host cells. These processes encourage the exchange of genetic materials amongst organisms.
Cloning is the process of introducing a foreign DNA molecule or gene into another organism. With genetic engineering, the gene or DNA of an organism can be removed and manipulated in vitro to acquire certain beneficial characteristics. After a successful in vitro manipulation, the mutant heritable material or DNA can then be re-introduced into a host cell or vehicle that will transport the manipulated gene into another organism. Genes are the chemical blueprints that determine an organism’s phenotype. When the DNA or genes of one particular organism is moved to another organism, the genetic traits or genotype of the former organism will be transferred to the recipient organism.
Phenotypes are the observable features of gene expression. They reveal the physical appearances or metabolic capabilities of organisms. Genotype on the other hand refers to all the genes (DNA) that encode characteristics/traits of an organism. During genome or DNA replication in a cell, the genetic information encoded in the gene is usually transformed or changed into the molecule that the gene encodes, usually a protein molecule. This process of turning the information from the gene in the DNA into a protein molecule or other molecules that it encodes is generally known as gene expression. Since not all genes are expressed in a cell, it is however noteworthy that only expressed gene can contribute to the phenotype of an organism. If the genes are not expressed during DNA replication, the information it contained cannot significantly contribute to the organism’s phenotype.
Gene expression in living cells mainly involves the synthesis of RNA and protein. This process of RNA and protein synthesis (otherwise known as gene expression) occurs all the time in every living cell. The gene is the foundation of most molecular biology techniques, and this is usually due to the notion that the gene harbours the heritable genetic material of the cell. Since one of the most important genetic activities that living organisms undergo during each round of their cell division is the replication of their genome, understanding this important biological process (i.e. genome or DNA replication) and how the cell’s genome works has enabled molecular biologists to deliberately manipulate the organism’s gene or DNA at a molecular level.
This helps scientists to synthesize desired products that are of commercial, health, industrial and environmental benefits. Genetic engineering allows organisms to acquire targeted combinations of new genes or DNA from various sources so that they can begin to act or metabolize in certain ways. It allows organisms to acquire those genetic traits they naturally lacked via an artificial means especially through molecular cloning. Through advanced biotechnological processes, certain desired target genes of living organisms can be manipulated with a view to influencing their natural traits. Genetic engineering and/or the molecular manipulation of organisms usually lead to the production of transgenic organisms and genetically modified organisms (GMOs) with various economic benefits.
Cooper G.M and Hausman R.E (2004). The cell: A Molecular Approach. Third edition. ASM Press.
Das H.K (2010). Textbook of Biotechnology. Fourth edition. Wiley edition. Wiley India Pvt, Ltd, New Delhi, India.
Davis J.M (2002). Basic Cell Culture, A Practical Approach. Oxford University Press, Oxford, UK.
Mather J and Barnes D (1998). Animal cell culture methods, Methods in cell biology. 2rd eds, Academic press, San Diego.
Noguchi P (2003). Risks and benefits of gene therapy. N Engl J Med, 348:193-194.
Sambrook, J., Russell, D.W. (2001). Molecular Cloning: a Laboratory Manual, 3rd edn. Cold Spring Harbor Laboratory Press, New York.
Tamarin Robert H (2002). Principles of Genetics. Seventh edition. Tata McGraw-Hill Publishing Co Ltd, Delhi.