Bacteria, Harmless
and Harmful
Bacteria are so tiny; they can only be seen under a
microscope. Bacteria are one celled tiny microorganisms. Most people are
unaware that most bacteria are harmless. Harmless bacteria are called
nonpathogenic bacteria, While a bacterium that is harmful is called
pathogenic.
Nonpathogenic or harmless bacteria make up over 70 percent of all bacteria.
Bacteria can be found in water, in and on our bodies, and on all surfaces.
Some of these bacteria can be found in our stomach and intestines. This
bacterium is what helps us digest our food.
Pathogenic or harmful bacteria make up the other 30 percent of all bacteria.
Pathogenic bacteria are also referred to as germs. Pathogenic means disease
causing.
Pathogenic bacteria can be broken down into three groups. The three groups of
pathogenic bacteria are Cocci, Bacilli and Spirlla. Cocci can also be broken
down into three groups as well: Staphylococci, Streptococci and Diplococci.
Cocci are bacteria that grow in groups are pus producing. Cocci are
responsible for causing boils and pustules. Bacilli produce disease like
influenza and TB. Spirillum causes disease such as syphilis.
Bacteria need dark, warm and damp conditions to grow. Bacteria can grow as
well as reproduce. Bacteria split in two when they reach maturity. When a
bacterium divides it is called mitosis. Bacteria can divide over and over
again. In a single day, one bacterium can create over 32 million copies of
itself. Understanding bacteria’s needs to survive is one way to help prevent
its growth. While a virus is pathogenic as well it is smaller than bacteria. A
virus needs a host to survive, while bacteria can grow on it’s own.. Because a
bacterium doesn’t need a host to survive it can reproduce rapidly.
One aspect of bacteria is that when conditions change and they are unfavorable
for bacteria then go into hibernation or sort and form an outside covering
called a spore. A spore is bacteria in a dormant state. Spores are very
resilient. When conditions improve, the bacteria will once again become
active. Disinfection can not kill spores, only sterilization can.
Disinfection is one of three levels of decontamination.
To lessen the number of bacteria one can sanitize an area. The next level of
decontamination is disinfection. Disinfection rids the area of all bacteria
except for spores. Sterilization is the last level of decontamination.
Sterilization kills all bacteria including spores.
Bacteria are an important group of living organisms.
Most of them are microscopic and unicellular, with a relatively simple cell
structure, lacking a cell nucleus, and organelles such as mitochondria and
chloroplasts. A tough protective layer called a cell wall encloses almost all
kinds of bacteria. The cell wall gives the bacterium its distinctive shape and
enables it to live in a wide range of environments. A capsule, a slimy layer
outside the cell wall, further encloses certain species. The capsule causes
the cell to be resistant to destructive chemicals. All bacteria possess a cell
membrane, an elastic, bag-like structure immediately inside the cell wall.
Small molecules of food enter the cell through pores in this membrane, but
large molecules cannot pass through it. Inside the membrane is the cytoplasm,
a jellylike, soft substance. The cytoplasm contains chemicals called enzymes,
which help build cell parts and break down food.
Bacteria can be categorized as living cells unlike viruses. Bacteria are found
everywhere from the tallest mountains to the deepest parts of an ocean on
earth. The air is replete with bacteria. Certain bacteria spend their whole
lives in the atmosphere, reproducing and growing in the clouds. Although
bacteria lack distinct nuclear structures common to the cells of higher
organisms like animals and plants and are able to reproduce successfully and
transfer genetic information from one generation to the next. Motile bacteria
can move about, either using bacterial gliding, flagella or changes of
buoyancy.
Almost 99% bacteria are helpful. Disease is caused by only a few of them.
Water, food, and air carry bacteria from one person to another. Bacteria can
be classified into three types on the basis of shape. The sphere shaped
bacteria, rod shaped bacteria and spiral bacteria are the three types.
Helpful bacteria
- Certain types of bacteria live in the intestines of
human beings. They help in digestion and in destroying the harmful
organisms. Intestinal bacteria also produce some vitamins required by the
human body.
- Certain bacteria help break down lactose in the
digestive tract.
- It is observed that Infants who were administered the
bacteria Lactobacillus reuteri or Bifidobacterium had fewer and shorter
episodes of diarrhea.
- Fermented milk containing the live bacteria
Lactobacillus casei helps in eradicating harmful bacteria Helicobacter
pylori in children.
- Saccharomyces boulardii is found to reduce the risk
of antibiotic-associated diarrhea in children.
- Some bacteria present on the skin protect us from the
spread of certain fungus.
- It was found that DNA damage was significantly
reduced by all six strains of lactic acid producing helpful bacteria tested
with the exception of Streptococcus thermophilus.
- There are many types of bacteria that live inside the
mouth, nose, throat, and intestines of humans and animals. These bacteria
get a place to live and feed while keeping other harmful microbes from
taking up residence.
- Certain stomach bacteria may work harmoniously with
our immune system. There are billions of stomach bacteria, which are
friendly or beneficial bacteria.
- There are some friendly bacteria such as intestinal
flora or micro flora which are good for human health. These healthy stomach
bacteria are helpful to release many useful vitamins such as vitamin B and
vitamin K, etc. The most important task that stomach bacteria do is to
maintain normal pH level or acid level of human stomach.
Harmful bacteria
- Certain bacteria act as pathogens and cause tetanus,
typhoid fever, pneumonia, syphilis, cholera, food-borne illness and
tuberculosis.
- Streptococcus bacteria may cause small infections
like strep throat and some serious diseases like pneumonia. Certain
streptococci may be fatal.
- Bacteria that usually live harmlessly in the body may
cause infections when a person's resistance to disease is reduced in
conditions such as AIDS (Acquired Immune Deficiency Syndrome).
- Not all stomach bacteria are beneficial, some of the
stomach bacteria enter the body through the mouth, and they can survive in
the acidic conditions in the stomach and can cause serious diseases and can
be fatal.
- Campylobacter is a group of bacteria that can create
illnesses in humans and is a common cause of food poisoning.
- Harmful bacteria in food cause botulism, which can
cause paralysis or even death if even one millionth of the bacterium is
ingested.
- Yersinia pestis or bubonic plague, is a rod-shaped
type of bacterium which is well known for its harmful nature.
Bacteria-carrying fleas found on animals such as rats and mice transmit the
bacteria that are believed to have caused the deaths of millions of people
in human history.
Antibiotics are widely used to kill harmful bacteria.
Washing hands with antiseptic soap will kill the bacteria. Don’t eat or drink
from unhygienic places. One should realize that while good bacteria can
survive without us, we cannot survive without good bacteria.
Olives and yogurt are products of bacterial
decomposition. The more decomposition the more flavor the food has. Modern
technology can also “reprogram” bacteria to isolate insulin which is used as a
medicine. Instead of killing animals in the slaughterhouse and getting it out
of their pancreas the insulin that diabetics need comes from bacteria (Johnson
347).
Bacteria can grow in the human bodies, which can have the bad side effect of
causing illness. Bacteria that make humans sick can come through food or
water. Harmful bacteria in food cause botulism, which can cause paralysis or
even death if even one-millionth of the bacterium is consumed. This harmful
bacteria can grow in improperly canned food and it lives in soil. Salmonella
is another harmful bacterium. The symptoms aren’t nearly as bad as botulism
but it can still be fatal. The best way to avoid getting salmonella is to wash
kitchen work areas with hot, soapy water (Johnson 349).
Pasteurization is the heating up of the substance to kill any unwanted
bacteria and its toxins (Todar 1). When the pasteurized substance is cooled
down to a few degrees above freezing it eliminates bacteria as well to get rid
of the bacteria in the substance.
Bacteria
Bacteria can be found almost anywhere on the
globe, even in the most remote places, bacteria can be found. Bacteria
belong to the oldest group of organisms. A 3.5 billion-year-old fossil
contains ancient bacteria (Johnson 339). The tiniest organisms can be filled
with bacteria. You cannot see bacteria with out microscope. People can grow
bacteria to find out different things. More bacteria will grow yogurt that
has more milk fat.
There are three common shapes of bacteria: spiral, rod-shaped, and
spherical. The spherical shaped bacteria are usually formed in long chains.
Rod-shaped bacteria looks like abstract art and spiral bacteria looks like
DNA strands (Johnson 339). Even though they may look interesting, they can
have an awful effect. One type of spiral shaped bacteria sometimes causes
kidney and liver damage. This spiral-shaped bacterium is called Leptospira.
Staphylococcus aureus is a spherical bacteria that can cause skin infections
(Johnson 339).
Although there are three major shapes of bacteria, there is a certain
general structure to all bacterial cells. There is no nucleus in a
bacterium. All of the genes of the bacterium are located on one molecule of
DNA in the middle of the bacterium. Some bacteria.