Transgenic organisms are those organisms with different sets of genes acquired from a different organism. If genetic material from another species is added to another host organism, the resulting organism is generally called a transgenic organism. Genetically modified organisms (GMOs) are those plants, animals or microorganisms whose genetic makeup or DNA has been changed through genetic engineering. Genetically modified microorganisms have applications in various areas including but not limited to agriculture, health, research, food, textile and paper industries.
Some of the beneficial outcomes of manipulating microorganisms at the molecular level include increased food production and reliability, and increased agricultural yields. The genetic manipulation of microorganisms also leads to enhanced taste and nutritional value of crops. It also leads to decreased losses of crops due to various biotic and abiotic environmental stresses. Microbes serve primary and secondary roles in food fermentation and in food spoilage, and they can produce enzymes or other metabolites used in food production and processing. Microorganisms play significant roles in food production. Wine, bread, yoghurt and cheese are common examples of ancient foods, still popular today, that depend on microbial ingredients and activities.
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Microorganisms have been used and manipulated since time immemorial to produce a wide variety of goods and services including cheese, yoghurt, bread and wine (as aforesaid) through the process of fermentation even at a time when the scientific basis behind these processes were unknown. Microbes whose genes have been manipulated by biotechnological processes have been used to improve agriculture and also to enhance the environment especially in the area of cleaning up the environment and making it free from wastes that harm human health.
Mutation and selective processes have allowed scientists to effectively manipulate microbes at the molecular level. But the advent of recombinant DNA technology and/or genetic engineering as aforementioned has revolutionized microbial manipulation at the molecular level. Recombinant DNA (rDNA) technology (genetic engineering) is the biotechnological technique or process that is used to cut a known DNA sequence of an organism (known as the donor organism) and then introduce the modified and cut DNA molecule into another organism (known as the recipient organism). One of the major reasons of doing this is to alter the genotype of the recipient host organism so that its phenotype during genome (DNA) replication could also be changed into a desired and expected outcome.
Some of the approaches involved in the genetic engineering of a microorganism’s DNA or gene are highlighted in this section; and these measures are usually employed to generate novel DNA molecules in a host organism. These approaches are:
- Disruption of undesirable gene functions
- Over-expression of desired genes
- Improving protein properties
- Improving or enhancing product yield
- Enhancing product metabolic pathways
- Removing competing metabolic pathways
- Eliminating feedback regulation mechanisms
- Manipulating transcription regulatory genes
BENEFITS OF MOLECULAR MANIPULATION OF MICROORGANISMS
- Molecular manipulation of the gene helps biologist to study gene arrangement.
- It helps us to understand how genes are expressed and regulated in the cell.
- Gene manipulation allows us to obtain a changed and desired protein product.
- Gene manipulation leads to improved and increased production of a desired product.
- It also helps scientist to suppress the expression of a particular gene in an organism.
- With gene manipulation, multiple copies of a DNA molecule or a segment of a gene could be artificially produced.
- Gene manipulation allows us to create transgenic organisms and genetically modified organisms.
- It also allows us to create organisms with desirable or altered traits.
- Gene manipulation helps scientists to study how genes are turned “on” and “off”.
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