What is Microbiology?
- The scientific study of microorganisms is called microbiology, which are tiny living organisms that are often too small to be seen with the naked eye. These microorganisms include bacteria, viruses, fungi, algae, and protozoa. Microbiologists examine the biology, genetics, physiology, ecology, and taxonomy of these microorganisms to better understand their roles in various biological processes, including disease, environmental processes, and industrial applications.
- It is a subject that deals with living organisms that are individually too small to be seen with the naked eye. It considers the microscopic forms of life and deals with their reproduction, physiology, participation in the process of nature, helpful and harmful relationships with other living things, and significance in science and industry.
- It plays an important role in various fields, including medicine, as it helps to identify and understand the causes of infectious diseases and develop treatments and vaccines. It is also essential in biotechnology, food and beverage production, environmental science, and agriculture. Microbiologists study how microorganisms interact with each other and their environment how they can be used for various beneficial purposes or how they can be controlled when they cause harm.
History of Microbiology
- Humans have always been affected by diseases, which were originally believed to come from the gods to punish evildoers.
- Hippocrates, the father of medicine, said that bad health is caused by changes in the air, wind, water, climate, food, nature of the soil, and people’s habits.
- Verro (117–26 BC) put forward a theory that disease was caused by animated particles that are invisible to the naked eye but are carried in the air into the body through the mouth and nose.
Fracastorius (1500 BC) proposed that the agents of communicable disease were living germs, which could be transmitted by direct contact between humans and animals and indirectly by objects, But there is no proof due to lack of experimental evidence. - Antony Van Leeuwenhoek (1632-1723 G.C.), the father of microbiology, observed “animals” using a simple microscope with a single lens. He was the first person to correctly describe the different shapes of bacteria. However Leeuwenhoek was not concerned about the origin of the microbe; Many other scientists were searching for explanations for the spontaneous appearance of living things from rotten meat, stagnant ponds, fermented grains, and infected wounds. Based on this observation, two major theories were formulated.
(1) Theory of Abiogenesis.
(2) Theory of Biogenesis.
The theory of Abiogenesis is related to the theory of spontaneous generation, Stating that living things originated from nonliving things.
- Aristotle (384–322 BC): Founder of the theory of spontaneous generation. He observed the spontaneous survival of fish in dry ponds when the pond was filled by rain.
- Francesco Redi (1626-1697): He is the scientist who first tried to set up an experiment to disprove spontaneous generation.
– He put the meat in a bottle and covered it with gauze.
– He observed that flies lay eggs from which insects develop.
– He said that insects have evolved not from flesh but from fly eggs.
The theory of Biogenesis states that life comes from pre-existing life.
- Louis Pasteur (1822-1895 GC) was the scientist who refuted the Theory of biogenesis. He designed a large curved flask (Pasteur swan neck flask) and housed a sterile growth broth medium. Air moves freely through the tube, But the dust particles are trapped in the curved part of the flask. No microbial growth was observed in the broth. Therefore Pasteur proved that micro-organisms enter the substrate through air and micro-organisms do not grow spontaneously.
The major contribution of Louis Pasteur:
1. Microbial theory of fermentation.
2. Principles and practice of sterilization and pasteurization.
3. Control of diseases of silkworms.
4. Development of vaccines against anthrax and rabies.
5. Discovery of streptococci.
The germ theory of disease: The complete establishment of the germ theory of disease depended on the work of a German scientist, Robert Koch (1843-1910).
Major achievements of Robert Koch:
1. Discovery and use of solid medium in bacteriology.
2. Discovery of causative agents of tuberculosis and cholera.
3. Koch’s phenomenon.
4. Koch’s postulates.
Classification of Microbiology:
(A). Pure Microbiology: Pure microbiology refers to the study of microorganisms and their characteristics without direct applications or practical considerations. It focuses on understanding fundamental aspects of microorganisms, including their structure, genetics, physiology, and ecological roles. In pure microbiology, the aim is to expand knowledge about microorganisms and advance scientific understanding in the field. Pure microbiology provides the basis for applied microbiology, where the knowledge gained is used for practical purposes.
Branches of pure microbiology:
(1). Microbial cytology: The study of microbial cell details of microorganisms.
(2). Microbial physiology: Study of how the microbial cell functions biochemically.Includes the study of microbial growth, microbial metabolism, and microbial cell structure.
(3). Microbial ecology: The relationship between microorganisms and their environment.
(4). Microbial genetics: The study of how genes are organized and regulated in microbes about their cellular functions is closely related to the field of molecular biology.
(5). Microbial taxonomy: Study of naming and classification of microorganisms.
(6). Molecular microbiology: The study of the molecular principles of the physiological processes in microorganisms.
(7). Microbial diversity: Investigating the vast diversity of microorganisms on Earth, including those that have not yet been cultivated in the laboratory.
(B). Applied microbiology: Applied microbiology is a branch of microbiology that focuses on practical applications of microorganisms. It involves using the knowledge and understanding gained from pure microbiology to solve problems and develop beneficial technologies in various fields such as medicine, agriculture, biotechnology, and environmental science. Overall, applied microbiology transforms knowledge gained from pure microbiology into practical solutions for a variety of fields. It involves harnessing the abilities of microorganisms to solve challenges and improve processes in medicine, agriculture, biotechnology, and environmental science.
Branches of applied microbiology:
(1). Pharmaceutical microbiology: Study of microorganisms that are related to the production of antibiotics, enzymes, vitamins, vaccines, and other pharmaceutical products. They also develop methods to preserve and deliver these products effectively.
(2). Medical microbiology: Study of microorganisms that are related to their role in human illness. Microbiologists work in clinical laboratories to identify and study disease-causing microorganisms. They also develop vaccines and antibiotics. In the field of medicine, applied microbiology plays a crucial role in the diagnosis, treatment, and prevention of infectious diseases. Medical microbiologists study microbes to understand their pathogenesis, develop effective antimicrobial therapies, and improve overall human health. This branch also involves clinical microbiology, where microorganisms are identified and studied in clinical samples to aid in patient diagnosis and management.
(3). Industrial microbiology: Microorganisms are used in industrial processes like fermentation, food and beverage production, pharmaceuticals, and biofuel production. For example, yeast is used to ferment beer and bread, while bacteria can produce antibiotics.
(4). Agricultural Microbiology: Microbes are used in agriculture to improve soil fertility, control pests, and enhance crop yields. For example, certain bacteria can fix nitrogen in the soil, making it available to plants.
(5). Biotechnology: Microorganisms are used in biotechnological processes, including genetic engineering and the production of bio-based products. Genetic modification of microorganisms has led to the development of many valuable products, such as insulin and biodegradable plastics.
(6). Food microbiology: This field is concerned with the study of microorganisms in food and food processing. It ensures the safety and quality of food products and can also be used for processes like fermentation in cheese and yogurt production.
(7). Bioremediation: Microorganisms are used to clean up pollutants in the environment, such as oil spills and toxic waste. They can degrade hazardous chemicals into less dangerous ones.
(8). Aquatic microbiology: Study of microorganisms, and their activity in freshwater or marine water including lakes, rivers, sea, etc.
- Introduction to Virology
- Introduction to Bacteriology
- Introduction to Parasitology
- Introduction to Immunology
- Introduction to Mycology
<Explore the extraordinary world of Microbiology further by visiting: https://microbiologysociety.org/why-microbiology-matters/what-is-microbiology.html
References
- Microbiology Society
- Department of Biological Sciences- University of Pittsburgh
- ScienceDirect
- Study.com
- Study smarter UK
- Learn Biology Online
- Toppr
- Biologydictionary.net
- Brain Gain Magazine
- The University of Kansas
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