Bacteria: Essential for Living Organisms or Deadly Pathogens?

Germs have a terrible reputation as deadly pathogens. Many people think that germs have to be killed, yet our bodies are hosts to trillions of bacteria. In fact, bacteria, fungi, and protozoa outnumber a person's cells by ten to one! Germs are a part of our bodies. They help us digest organic compounds, regulate appetite and metabolism, and regulate our immune systems. The majority of germs live in the digestive system. The human body produces 99 enzymes to break down starches and other polysaccharides, and bacteria in the gut can produce 250 more enzymes to break down sugars, greatly increasing the energy one can extract from a meal.

By killing germs with antibiotics, people have actually strengthened bacteria. For example, penicillin was first used to treat staph infections. The bacteria who were immune to penicillin lived and reproduce, creating a population of penicillin-immune germs. Then, methicillin was used to treat penicillin-immune staph infections, but the bacteria who were immune to methicllin survived and reproduce, creating the deadly super bug, MRSA. Hunter Spence, a 12-year-old girl, almost died in five days from MRSA. In addition, this disease can be spread through an open cut and an unwashed hand. Although several of people use alcoholic sanitizers like Purell to kill many germs, it is no replacement for hand washing.

The Human Microbiome Project, a five year study, is trying to sort the good microbes from the bad. Because different species of bacteria live on every separate structure of the body, there are thousands of microbes to be discovered. By studying how the germs interact with our cells, scientists might find better ways to improve health and to fight disease.

How does the immune system tolerate these trillions of invaders? Certain cells takes samples of microbes in the body. If they see the same type of microorganism, the cells secrete a substance that tells the immune systems to let the germs live, but for this reaction to occur, one must be exposed to harmless microbes as an infant. Modern sanitation kills many of these microbes. Scientists believe that if babies are not exposed to harmless microbes, they are more likely to have allergies and asthmas.

Some germs have interesting effects on the body. Heliocobacter pylori can cause gastric ulcers and stomach cancer, but it also protects against esophagus cancer. Since it is disappearing, the rate of stomach cancer has decrease, yet the rate of esophagus cancer and asthma have increased. Scientists have already started to introduce microbes in food or pills. Dannon's Acivtia is a yogurt that contains Bifidobacterium animalis, a bacteria that helps digestion. Other germs have intriguing effects. Mycobacterium vaccae was given to a sample of cancer patients. The patients felt better even if the cancer was getting worse. The bacteria was working as a antidepressant without the side effects of insomnia and anxiety.

Germs affect our lives in unimaginable ways. Even though most believe that micro organisms are dangerous, bacteria are essential to all living life. Scientists can now utilize these microbes to improve quality of life around the world. The interesting part is that trillions of bacteria live on our bodies, helping us to survive and preforming many functions. Will people use too many antibiotics to create a super bug that can extinct the human race? Are there other bacteria like the M. vaccae that can cure diseases or act as medicine?

Sources
Madigan, Michael, Martinko, John, "Brock Biology of Microorganisms"