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Introduction to Organisms

Author(s): Deanne Erdmann, MS

Ecological Importance of Prokaryotes

The majority of bacteria are not harmful and, in many cases, are beneficial to survival. Prokaryotes are the decomposers of the Earth. Many prokaryotes obtain energy by breaking down organic molecules and, in the process, make nutrients available for use by other organisms. Prokaryotes are the only organisms to metabolize inorganic nutrients such as sulfur, iron and nitrogen. Nitrogen recycling, or nitrogen fixation, is unique to Prokaryotes and is the only biological mechanism that makes atmospheric nitrogen available for the production of organic compounds. Mutualistic bacteria live inside our intestines aiding in digestion while other bacteria suppress the growth of yeasts and other microbes by altering pH levels in our body.

In the late 1800s, Louis Pasteur and other scientists linked bacteria to disease. Robert Koch was the first to identify the organisms that cause tuberculosis and anthrax. Since then, other pathogenic prokaryotes have been identified and linked to diseases, such Lyme's disease, tetanus, cholera, diarrhea, botulism and syphilis. In industry, bacteria have been used in bioremediation and as metabolic factories that produce acetone as well as pharmaceuticals like insulin and antibiotics. Bacterial metabolic abilities are useful in separating sulfur compounds from copper and uranium in mining low grade ores.