Bacteria, Biotechnology, and Society - Essay Example

April 10, 2006 Bacteria, Biotechnology and Society The term “bacteria” has often been understood as one that causes diseases, food spoilage, decomposition, and even death. A number of great men in the world history succumbed to illnesses caused by these microorganisms. Among them were Alexander the Great who died of an infection of the lungs, Pharaoh Ramses V who may have died of small pox, and Amadeus Mozart who may have died of rheumatic fever (Wassenaar). These microorganisms are quite ubiquitous that scientists have delved into research to know more about them and find good use with their numbers. This paper is aimed at looking into the morphology and physiology of the bacterial cell and discusses its significance in the field of medicine, biotechnology and society. All life forms are classified into five major kingdoms. These are Kingdoms Monera, Protista, Plantae, Fungi and Animalia. Bacteria are the lone members of the Kingdom Monera. The archaebacteria are believed to be the most primitive type and can now be found only in hot springs and areas of low oxygen concentration (Farabee). According to Joklik et al. (10), bacteria, or prokaryotes, are free-living, energy-producing, single-celled organisms that reproduce asexually through binary fission. They contain genetic information and have the biosynthetic systems necessary for growth and reproduction. Unlike eukaryotes, they do not have membrane-bound organelles such as the nucleus, mitochondria, lysosomes, endoplasmic reticulum, or golgi apparatus. They also do not have the 80s ribosome units that eukaryotes have. Instead they have a 70s ribosomes and a nucleoid which contain their genetic material in the form of a double-stranded deoxyribonucleic acid (DNA) that replicates amitotically. They move through their single-filament flagellar structures, unlike the 9+2 flagellar configuration of eukaryotes. They have a rigid cell wall, with the exception of Mycoplasma, whose chemical nature renders a bacterium gram-positive, gram-negative or acid-fast organism. Morphologically, they occur as spheres (cocci), rods (bacilli), or as spiral-shaped cells. Bacteria can be classified by their method of energy acquisition (Joklik et al. 40). They can either be autotrophic or heterotrophic. Autotrophic or lithotrophic bacteria utilize carbon dioxide as the sole source of carbon and synthesize from it all other carbon derivatives. They require only water, inorganic salts and carbon dioxide for growth. Autotrophs can either be photosynthetic or chemosynthetic. The former uses radiant energy to drive their activities while the latter derive energy from the oxidation-reduction reactions using simple inorganic electron donors such as hydrogen, sulfur and ammonia. Cyanobacteria are examples of photolithotrophs. Heterotrophic bacteria, on the other hand, are unable to utilize carbon dioxide as their carbon source but would need that it be supplied in an organic form. Bacteria that cause diseases to man belong to this group. Bacteria require tremendous amounts of energy to drive their activities as evidenced by the speed by which they divide and the rate at which they drive enzymatic reactions. They need energy to convert chemical and radiant energy into biologically useful form through the processes of respiration, fermentation and photosynthesis. Respiration makes use of oxygen as the ultimate electron acceptor. In fermentation, food material is being converted to ethanol with carbon dioxide as a byproduct. Photosynthesis converts energy from the sun into useful chemical energy. Energy produced in these processes comes in the form of adenosine triphosphate or ATP. Most bacterial reactions are associated with the production of too much heat because of the rate at which they proceed. Heat evolved is considered as excess energy which is of no use to the host organism, thus making bacteria less efficient converters of free energy than organisms with slower metabolic rate. The use of bacteria in recombinant DNA technology is now gaining popularity as scientists exploit the properties of bacterial cells to develop cures for certain diseases, as well as a means to speed up production of raw materials, for example in the food industry. Parts of a bacterial genome or plasmids can be transferred to another member of its own species and at times even to other species. One transfer mechanism is called transformation. It involves the uptake of a naked DNA by a recipient cell from a donor cell and incorporating the genetic material into its own chromosomes resulting to the production of a recombinant DNA. This process can be found in the generation of what we call genetically modified organisms or GMOs (Hunt). The effect of bacteria in lives of men often comes in the form of diseases, many of which are lethal ones. Time was when men feared coming in contact with these microorganisms for fear that they might contract diseases which could lead to their death, but with the advances in research and development in the pharmaceutical industry, diseases which were once regarded as life-threatening, now have a higher cure rates. The discovery of penicillin has paved the way for the eradication of diseases known to man. Antibiotics such as penicillin bind to the penicillin-binding proteins located at the cell wall of bacteria. They inhibit the formation of peptidoglycans which lead to the enzymatic autolysis of the cell wall, thereby killing the bacterial cell (Hunt). The over use and misuse of antibiotics, though, would cause bacterial resistance which poses an even bigger problem for the patient. This is the reason why professional help is always advised before administering antibiotics. Today bacteria are known to play a key role in field of medicine and biotechnology (Ramel). Several strains of Streptomyces sp. serve as key component of some of the known antibiotics today such as Streptomyces remosus in tetracycline, Streptomyces erythreus in erythromycin, and Streptomycin noursei in nystatin. The food industry has also found good use with them, as they are now known producers of certain amino acids used as food additives. Examples of these are glutamic acid in MSG, lysine in breads, and phenylalanine and aspartic acid in aspartame, a soft drink sweetener. Bacteria also act as enzymes which catalyze much of the biological processes in nature. The vitamin industry, which is worth 1 billion USD per year, can now synthesize their products biochemically. The most important of which is the production of vitamin B12 which is made possible with the help of Pseudomonas denitrificans. Bacteria also play a key role in mining, such as Thiobacillus ferrooxidans which act as a catalyst in the oxidation of metal sulfides. Biodegradable plastics are now being manufactured to address the problem of plastic-build-up in landfills, and the major player here is Alcaligenes eutrophas. In vinegar and wine making, bacteria aid in the fermentation of ethanol to produce acetic acid. In the field of medicine, the advent of vaccines has greatly reduced the risks of several death causing diseases such as hepatitis, measles, chicken pox, and tuberculosis, among others. Epidemics have been controlled and millions of lives have been saved with the use of live bacterial strains which enable humans to develop immunity against known pathogens. In the field of cancer treatment, bacteriophages are now being studied to eradicate cancer cells without causing harm to the normal functioning ones which is a known adverse effect of chemotherapy. Clearly the field of science and biotechnology has come a long way in discovering the great many uses of bacteria to man’s advantage. More researches and clinical studies are underway in quest for more knowledge of this microscopic yet complex form of life that is the bacterial cell. Works Cited Farabee, M.J. Biological Diversity: Bacteria and Archaeans. 2001. 07 Apr. 2006 . Hunt, Richard. "Bacteriology." Microbiology and Immunology online. 06 April 2006. University of South Carolina School of Medicine. 07 Apr. 2006 . Joklik, Wolfgang, Hilda Willett, and Bernard Amos. Zinsser Microbiology. 18th ed. : Prentice Hall, 1984. Ramel, G. Bacteria and Technology. 11 November 2005. Earth-Life Web Productions. 07 Apr. 2006 . Wassennar, T.M. "Bacterial Diseases in History." Virtual Museum of Bacteria. 08 March 2005. Foundation of Bacteriology. 07 Apr. 2006 . Read More