Nutritional types of bacteria

Bacteria are organisms that we may not be able to see from the naked eye but they are present everywhere even in the areas where human beings or other animals could not survive. They are also the first-ever species to come into existence on this planet. Now, this makes one excited to know exactly what bacteria and their types are.

What are bacteria?

Bacteria are microscopic organisms that are single-celled and present almost in all places around the world, let it be damp hot weather or icy cold glaciers. The first organisms to appear on earth dates back to 4 billion years and are bacteria. It is found that the human body contains 10 times a greater number of bacteria than human cells. Most of the bacteria in the human body are purely harmless rather they are helpful. Bacteria occur in various shapes such as spheres, rods, and even spirals. The disease-causing bacteria are called pathogens.

Examples of bacteria:

Streptococcus pneumoniae

Thiobacillus novellus

Staphylococcus aureus

Escherichia coli

Pseudomonas maltophilia

Listeria monocytogenes

Clostridium kluyveri

Lactobacillus acidophilus

Extremophiles bacteria are the ones that can withstand extreme conditions, these can survive in the places where no living organism can, these are;

• Halophiles- the bacteria found in a salty environment only

• Alkaliphiles- bacteria that can live under the Ph up to 10.5

• Acidophiles-bacteria that can survive acidic environments as low as Ph 0

• Psychrophiles-found in very cold temperatures like glaciers

The three types of bacteria

There are mainly three types of bacteria based on their shapes:

1. Spherical

These bacteria are shaped like a ball called cocci, and a singular bacteria is referred to as coccus.

Example-Streptococcus group of bacteria which are the pathogens causing “strep throat”

2.  Rod-shaped

These are also called bacilli (singular as bacillus). Some of these bacteria are also curved, known as vibrio.

Example for rod-shaped bacteria-Bacillus anthracis

3. Spiral

These are referred to as spirilla(singular, they are termed as spirillum).

Examples-Leptospirosis and syphilis are caused by such spiral-shaped bacteria.

Nutritional types of bacteria

Nutrition is used in energy production and biosynthesis; hence they are very important to all living organisms. Bacteria also require energy and nutrients to produce proteins and membranes. Carbon, nitrogen, iron, phosphorous, and various other molecules are required by bacteria. Some bacteria can produce pre-formed organic molecules to obtain energy, while others can produce their energy from inorganic sources.

There are two nutritional types of bacteria based on the energy source, which are further divided:

1. Chemotrophs(gains energy from chemical compounds)

1. Chemoheterotrophs

   1. Using oxygen such as all animals, protozoa, most fungi, and bacteria.

   2. Without using oxygen

Fermentative: Streptococcus

Electron transport chain: Clostridium

ii) Chemoautotrophs

monoxide-oxidizing bacteria

2. Phototrophs(utilize light as an energy source)

1. Photoheterotrophs

Green non sulphur bacteria, purple non sulphur bacteria

2. Photoautotrophs

   1. Using water to reduce carbon dioxide

cyanobacteria

2. Without Using water to reduce carbon dioxide

Anoxygenic photosynthetic bacteria(purple and green bacteria)

Based electron source:

1. Lithotrophs

• photo-lithotrophs

these gain their energy from light and use compounds such as H2S 

for example: on Chromatium okenii 

•  chemo-lithotrophs

bacteria gaining energy from the inorganic compound which is NH3

for example Nitrosomonas

2. Organotrophs

• photo-organotrophs 

gains energy from light and the organic compound, Succinate as the source for gaining an electron

example Rhodospirillum

•  chemo-organotrophs

the bacteria that gain energy from the organic compounds such as amino acids and glucose fall under this category

example Pseudomonas pseudoflora

some exceptions do survive in this case as there are species of bacteria that can either live on as chemo-lithotrophs or chemo-organotrophs,

The typical example in such a case is Pseudomonas pseudoflora because it can survive by using either H2S or glucose as its major source to gain an electron.

The types of bacteria in urine

Generally, human urine is filtered through the filtration system (kidneys) and urinary tract so it does not contain any bacteria. Although there are some bacteria in the urine which are present when a person is suffering from any of the UTIs(urinary tract infections). These bacteria are:

Escherichia coli

 Proteus mirabilis

 Klebsiella pneumoniae

 Staphylococcus saprophyticus

 Enterococcus faecalis

The most common among these bacteria is Escherichia coli (E. coli)

Applications and uses

 There are various uses and applications of several bacteria in human life but the most useful application is on an industrial scale which is best understood by the following table:

Conclusion

The topic of the nutritional types of bacteria has looked into what bacteria and types of bacteria are. Moreover, it has also looked into the nutritional kind of bacteria or nature of the bacteria, in great detail. The various uses of bacteria have been discussed under the topic. The FAQs section attempts to address the most probable queries that might arise. The FAQs section provides additional information which will aid a better understanding of the topic.