Careers in Microbiology

What is microbiology?
Microbiology is the study of living organisms of microscopic size.

It also be defined as the study of living organisms, a large diverse group of micro-organisms that exist as single cells or cell clusters; it also includes viruses, which are microscopic but not cellular.

As you know, a microbiologist is a scientist who studies tiny organisms called micro-organisms. He or she might have a Bachelor’s, Master’s, or doctoral (PhD) degree in microbiology.
There are many career fields within the science of microbiology.

CAREERS IN MICROBIOLOGY

A person may specialize in the study of just one particular category of micro-organisms. A bacteriologist is a scientist who specializes in bacteriology; the study of the structure, functions, and activities of bacteria.

Scientists specializing in the field of phyco-logy study the various types of algae and are called phyco-logists. Proto-zoologists explore the area of proto-zoology, the study of protozoaand their activities.

Those who specialize in the study of fungi, or mycology, are called mycologists.
Virology encompasses the study of viruses and their effects on living cells of all types. Virologists and cell-biologists may become genetic engineers who transfer genetic material (deoxyribonucleic acid or DNA) from one cell type to another. Virologists may also study prions and viroids, acellular infectious agents that are even smaller than viruses.
Other career fields in microbiology pertain more to applied microbiology that is, how knowledge of microbiology can be applied to different aspects of society, medicine, and industry. Some of these career fields are briefly described
below.

The scope of microbiology has broad, far-reaching effects on humans and their environment.


Agricultural Microbiology


Agricultural microbiology is an excellent career field for individuals with interests in agriculture and microbiology.

Included in the field of agricultural microbiology are studies of the beneficial and harmful roles of microbes in soil formation and fertility; in carbon, nitrogen, phosphorus, and sulfur cycles; in diseases of plants; in the digestive processes of cows and other ruminants; and in the production of crops and foods.

Many different viruses, bacteria, and fungi cause plant diseases. A food microbiologist is concerned with the production, processing, storage, cooking, and serving of food as well as the prevention of food spoilage, food poisoning, and food toxicity. 

A dairy microbiologist oversees the grading, pasteurizing, and processing of milk and cheeses to prevent contamination, spoilage, and transmission of diseases from environmental, animal, and human sources.


Biotechnology (Industrial Microbiology)


Biotechnology (industrial microbiology); the use of microorganisms in industry, is an excellent career field for individuals with interests in industry and microbiology.

Many businesses and industries depend on the proper growth and maintenance of certain microbes to produce beer, wine, alcohol, and organic materials such as enzymes, vitamins, and antibiotics. Industrial microbiologists monitor and maintain the micro-organisms that are essential for these commercial enterprises.

Applied microbiologists conduct research aimed at producing new products and more effective antibiotics. 


Environmental Microbiology and Bio-remediation:


The field of Environmental-microbiology, or microbial ecology, has become increasingly important in recent years because of heightened awareness and concern about dangers to the environment.

Environmental microbiologists are concerned about water and sewage treatment.

The purification of waste water is partially accomplished by bacteria in the holding tanks of sewage disposal plants, where feces, garbage, and other organic materials are collected and reduced to harmless waste.
Some micro-organisms, such as the iron and sulfur-utilizing bacteria, even break down metals and minerals. Bioremediation involves the use of micro-organisms to clean up after ourselves that is, to clean up landfills and industrial and toxic wastes. The beneficial activities of microbes affect every part of our environment, including soil, water, and air.

Environmental microbiology and bioremediation are excellent career fields for individuals with interests in ecology and microbiology.


Medical and Clinical Microbiology


Medical microbiology is an excellent career field for individuals with interests in medicine and microbiology.

The field of medical microbiology involves the study of pathogens, the diseases they cause, and the body’s defenses against disease.

This field is concerned with epidemiology, transmission of pathogens, disease-prevention measures, aseptic techniques, treatment of infectious diseases, immunology, and the production of vaccines to protect people and animals against infectious diseases.
The complete or almost complete eradication of diseases like smallpox and polio, the safety of modern surgery, and the successful treatment of victims of infectious diseases are due to the many technological advances in this field. A branch of medical microbiology, called clinical or diagnostic microbiology, is concerned with the laboratory diagnosis of infectious diseases of humans.

This is an excellent career field for individuals with interests in laboratory sciences and microbiology.


Microbial Genetics and Genetic Engineering


Microbial genetics involves the study of microbial DNA, chromosomes, plasmids, and genes. (Plasmids are small, circular molecules of extra-chromosomal DNA).


Genetic engineering involves the insertion of foreign genes into micro-organisms (usually into bacteria or yeasts). These foreign genes may come from any other organism (e.g., another micro-organism, an animal, or even a plant).

The primary purpose of inserting a foreign gene into a micro-organism is to create a microbe that is capable of either producing a product of importance to us or accomplishing some task of importance to us. Genetic engineering has applications in agricultural, environmental, industrial, and medical microbiology.
The intestinal bacterium E. coli has been used extensively in microbial genetics, genetic engineering, and microbial physiology. 

Microbial genetics and genetic engineering are excellent career fields for individuals with interests in genetics and microbiology.

 

Microbial Physiology  


Research in microbial physiology has contributed immensely to our understanding of the structure and functions of microbial cells.

What microbiologists learn about microbial cells quite often applies to cells in general. Microbial physiology is an excellent career field for individuals with interests in biochemistry and microbiology.


Paleo-microbiology


The field of paleo-microbiology involves the study of ancient microbes.

Although life is thought to have originated between 3.7 and 4 billion years ago, there are no cellular fossils available from that period. However, there are molecular fossils, molecules (usually lipids) that are known to be made only by organisms or, in some cases, only by particular organisms. Finding such molecular fossils in ancient rocks serves as evidence that life existed at that time.
*The earliest molecular fossils date back to between 3.7 and 4 billion years ago*.

Some Paleo-microbiologists examine and study skeletons and mummified human remains to determine the infectious diseases that occurred in ancient civilizations. Such studies often involve the recovery of microbial DNA from bone and mummified tissue samples. For example, finding Mycobacterium tuberculosis DNA in Egyptian mummies has revealed that tuberculosis existed as far back as 3000 BC.

Paleo-microbiology is an excellent career field for individuals with interests in anthropology, archaeology, and microbiology.



Parasitology


Parasitology, technically, any organism that lives on or in another living organism is called a parasite.

It would seem then, that the term parasite would apply to all the micro-organisms of our indigenous micro-flora the viruses and bacteria that live on or in the human body. However, the field of parasitology involves only the following three categories of parasites: parasitic protozoa, helminthes (parasitic worms), and arthropods (specifically, certain insects and arachnids). 

A parasito-logist studies these organisms and their life cycles in an attempt to discover the best ways to control and treat the diseases that they cause. 
 

Sanitary Microbiology


The field of sanitary microbiology includes the processing and disposal of garbage and sewage wastes, as well as the purification and processing of water supplies to ensure that no pathogens are carried to the consumer by drinking water.  

Sanitary microbiologists also inspect food processing installations and eating establishments to ensure that proper food handling procedures are being enforced.


Veterinary Microbiology


A wide variety of micro-organisms; including viruses, bacteria, fungi, and protozoa cause infectious diseases in animals. Control of such diseases is the concern of veterinary microbiologists.

The production of food from livestock, the raising of other agriculturally important animals, the care of pets, and the transmission of diseases from animals to humans are areas of major importance in this field. Infectious diseases of humans that are acquired from animal sources are called zoonoses or zoonotic diseases. 

Veterinary microbiology is an excellent career field for a person who is fond of animals and microbiology.


Difference Between Exotoxin and Endotoxin

Serial; no.
Property
Exotoxin
Endotoxin
1.
Bacterial source
Mostly from gram positive bacteria
Gram negative bacteria
2.
Relation to microorganism
Metabolic product of growing cell
Present in LPS of outer membrane of cell wall and released with destruction of cell or during cell division
3.
Protein content
Proteins usually with two parts (A-B)
Liquid portion of LPS of outer membrane
4.
Heat stability
Unstable can usually be destroyed at 60-80 degree centigrade
Stable can withstand autoclaving 121 degree centigrade for 1 hour
5.
Pharmacology
Each has a  highly characteristic mechanism of action
General such as fever, weakness aches and shock all produce the same effects
6.
Toxicity
High
 Low
7.
Fewer producing
No
 Yes
8
Representative disease
Gas gangrene,  Tetanus botulism, Diphtheria, Scarlet fever
Typhoid fever
9
Lethal dose
Small
Considerable larger
10.
Example
Streptococcus pyogens
 Salmonella typhus

Difference Between Bacteria and Fungi

What is meant by bacteria and fungi?

Bacteria:

Bacteria are unicellular free living organisms having
both DNA and RNA. They are capable of performing all
essential processes of life, e.g., growth, reproduction, and
metabolism.

They do not show any true branching except
Actinomycetales, the higher bacteria. Bacteria lack chlorophyll unlike blue green algae, which contain chlorophyll.

Fungi:
The name “fungi” is derived from “mykos” meaning mushroom. The fungi are eukaryotic organisms and they differ from the bacteria, which are prokaryotic organisms, in many ways.

The natural habitats of most of the fungi which cause
systemic mycoses are in organic wastes or debris or in
soil enriched by organic wastes.


Fungi differ from bacteria in a number of ways which is shown in the following table.


Differences between Bacteria and Fungi:



Serial no.
Basis for comparison
Fungi
Bacteria
1.
Cell type
Eukaryotic
Prokaryotic
2.
Optimum pH
3.8-5.6
6.5-7.5
3.  
Optimum temperature
22-30 degree centigrade.
30-37 degree centigrade (Mesophiles).
4.
Energy source
They obtain their energy from the used and pre-existing sources present in environment.
Obtain their energy from sugars, proteins and fats.
5.
Organelles
Organelles present
Cell lack organelles
6.
Light requirement
None
Some photosynthetic group requires light.
7.
Carbon requirement
Organic
Inorganic and organic
8.
Cell membrane
Present
Present below the cell wall.
9.
Cell wall structural components
 Chitin, cellulose or Hemi-cellulose.
Peptido-glycan
10.
Sugar concentration in laboratory media
4.5%
0.5-1%
11.
   Host
They grow their own
They do not need a host to grow.
12.
Reproduction
Asexual
  Can be either sexually or asexually
13.
Motility
They are non motile
Move through flagellum