2 WHAT IS BIOTECHNOLOGY? MICROBIAL BIOTECHNOLOGY What kind of relationship is there between microbes and biotechnology? National DNA Day is celebrated on April 25 each year to commemorate the completion of the Human Genome Project in 2003 and the discovery of DNA s double-helical structure in 1953. You have surely heard of or studied genes and genome. What are they? ONLINE RESOURCES What is biotechnology? Definition of biotechnology Biotechnology can be defined as using living organisms or their products for commercial purposes. As such, biotechnology has been practised by human society since the beginning of recorded history in such activities as baking bread, brewing alcoholic beverages, or breeding food crops or domestic animals. DNA All living organisms are composed of cells that contain a substance called DNA (deoxyribonucleic acid) in the chromosomes. The structure of DNA molecules contains information that is used by cells like a recipe book for the organism; that is, the characteristics of any living thing essentially are determined by the information in DNA. The words for the DNA recipe, called genes , are derived from a 4-letter alphabet (A, C, G, T). The entire recipe book is called the genome . Except for the sequence and number of letters in each recipe, DNA from any organism is chemically and physically the same. One of the great scientific breeding: producing, raising crop: agricultural product recipe: a set of instructions for preparing and cooking food to result in: to create 110 MICROBES AND BIOTECHNOLOGY discoveries of biotechnology is that DNA from any organism will function if it is transferred into any other organism! Combining DNA from different existing organisms (plants, animals, insects, bacteria, etc.) results in modified organisms with a combination of traits from the parents. The sharing of DNA information takes place naturally through sexual reproduction, but, however, sexual reproduction can occur only between individuals of the same species. Recent advances What s new since 1973 is that scientists have been able to identify the specific DNA genes for many desirable traits and transfer only those genes, usually carried on a plasmid or virus, into another organism. This process is called genetic engineering. Virtually any desirable trait found in nature can, in principle, be transferred into any chosen organism. An organism modified by genetic engineering is called transgenic.