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About Bacteria

Some Bacteria Keep Us Healthy, While Other Bacteria Make Us Sick. But... We Can Not Exist Without Them!

Triva - In 1675 Antony van Leeuwenhoek discovered bacteria.

Bacteria is plural (more than one) for bacterium.

Bacteria are tiny, living, one cell microorganisms that require a microscope to be seen, can be found in virtually any environment, and can be "good" - beneficial, or "bad" - cause infection and disease. Life in any form on Earth can not exist without these tiny microorganisms.

Where Bacteria Live

Bacteria are found everywhere. Like all living cells, each bacterium requires food for energy and building materials. Bacteria are found in plants, animals, and in and on the human body (called the host). About 600 types of bacteria live on the skin, and saliva contains about 6 different kinds of bacteria. Water, wind, insects, plants, and animals can carry bacteria. They also live on clothes, human hair, room-temperature foods, and surfaces in our homes, schools, and workplaces.

Most are harmless though, less than 1 percent of bacteria cause diseases in humans.

Bacteria that can cause disease are called pathogenic.

Bacteria are so small that a line of 1,000 could fit across a pencil eraser.

There are many different types and shapes of bacteria, but, typically they have one of three distinct shapes.

Commom Shapes of Bacteria

1) Cocci - (singular - coccus) Spheres - round

2) Spirilla - (singular - spirillum) Spirals

3) Bacilli - (singular - bacillus) Rods - oblong

Some bacteria (aerobic bacteria) need oxygen to live, and other bacteria (anaerobic bacteria) don't. What's amazing is that some bacteria can adapt to new environments by learning how to survive with or without oxygen.

Some bacteria, thermophiles, live in extreme heat, such as in the hot springs in Yellowstone National Park, while other bacteria, psychrophiles, thrive in the freezing cold, in the subfreezing temperature of the Arctic.

Extreme thermophiles, or hyperthermophiles, thrive at 235 degrees Fahrenheit near volcanic vents on the ocean floor.

Many bacteria prefer the milder temperature of the healthy human body.

You can't see, taste, or smell bacteria in food, but they can be present in food and multiply rapidly under the right conditions. That's why it's important to properly handle all foods.

How Bacteria Grow

Most bacteria multiply through a process called binary fission, a form of asexual reproduction in which the deoxyribonucleic acid (DNA) that holds all of the cell's genetic information doubles, the cell splits, and two independent cells are formed. One cell can double within 20 to 30 minutes.

Bad Bacteria Cause Disease

Some bacteria produce poisons called toxins, which also can make us sick. Bad bacteria in soil, water, or air can cause human, animal, and plant health problems. Examples of bad bacteria, such as Salmonella and Escherichia coli (E. coli), can cause illness in humans, even death.

Some Examples of Common Bacterial Diseases and Infections:

• Cholera
• Diarrhea
• Diphtheria
• Foodborne illness
• Haemophilus influenza
• Legionnaire's disease
• Meningitis
• Rheumatic fever
• Pertussis
• Pneumococcus (pneumonia)
• Sinusitis
• Skin infections
• Stomach ulcers
• Strep throat
• Tetanus
• Tooth decay
• Tuberculosis
• Typhoid
• Urinary tract infection
• Vaginal infections

Streptococci Bacteria

Good Bacteria For a Healthy Life

Out in the world...good bacteria aid in pollution control by consuming and breaking down organic matter and other pollutants in septic systems, sewage, oil spills, and soils.

Some bacteria are used in making foods like sauerkraut, vinegar, and pickles, yogurt, cheese, and buttermilk.

Bacteria are in our intestines, on our skin and in other orifices, and are vital to proper development of our immune system, to protect against microorganisms that could cause disease, and to the digestion and absorption of food and nutrients.

Harmless anaerobic bacteria, such as Lactobacilli, live in our intestines, where they help to digest food, destroy disease-causing microbes, fight cancer cells, and give the body needed vitamins.

Lactobacillus acidophilus is generally believed to be safe and have few side effects, but taken by mouth should be avoided in people with overgrowth of intestinal bacteria, intestinal damage, or a weakened immune system.

References:
U.S. Department of Health and Human Services (HHS)
National Institutes of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
NIH Publication No. 06-4914
January 2006
www3.niaid.nih.gov/
www.cfsan.fda.gov/