Microbiology: Encyclopedia - Microbiology

Microbiology

Microbiology (in Greek micron = small and biologia = studying life) is the study of microorganisms, including viruses, viroids, prions, prokaryotes and simple eukaryotes (e.g. molds and fungi). Microbes represent ideal model systems for study due to the fact that many can be grown quickly and easily in genetically uniform cultures (e.g. agar), which allows for the production of biological materials (e.g. protein or DNA) in reasonable quantities quickly, safely and inexpensively. However, viruses, viroids, and prions cannot grow in artificial media because they lack the processes neccesary to replicate on their own, without a host. Some bacteria such as Escherichia coli (E-coli) have become model organisms for the study of biochemistry and genetics and have allowed for the discovery of scientific principles that have subsequently been applied to other, more complex biological systems. Such as the replication of DNA and DNA transcription into mRNA by RNA polymerase and translation of mRNA into proteins by ribosomes.

Not all microbes grow quickly and easily. In actual fact, the most common estimates suggest that we have studied only about 1% of all of the microbes in any given environment. Thus, despite the fact that over three hundred years have passed since the discovery of microbes the field of microbiology is clearly in its infancy relative to other biological disciplines such as zoology, botany or even entomology.

The field of microbiology can be generally divided into several subdiscplines:

• Microbial physiology: The study of how the microbial cell functions biochemically. Includes the study of microbial growth, microbial metabolism and microbial cell structure.
• Microbial genetics: The study of how genes are organised and regulated in microbes in relation to their cellular functions. Closely related to the field of molecular biology.
• Medical microbiology: The study of the role of microbes in human illness. Includes the study of microbial pathogenesis and epidemiology and is related to the study of disease pathology and immunology.
• Veterinary microbiology: The study of the role in microbes in veterinary medicine.
• Environmental microbiology: The study of the function and diversity of microbes in their natural environments. Includes the study of microbial ecology, microbially-mediated nutrient cycling, geomicrobiology, microbial diversity and bioremediation.
• Evolutionary microbiology: The study of the evolution of microbes. Includes the study of bacterial systematics and taxonomy.
• Industrial microbiology: The exploitation of microbes for use in industrial processes. Examples include industrial fermentation and wastewater treatment. Closely linked to the biotechnology industry.

While microbes are often viewed negatively due to their association with many human illnesses, microbes are also responsible for many beneficial processes such as industrial fermentation (e.g. the production of alcohol and dairy products), antibiotic production and as vehicles for cloning in higher organsisms such as plants. Scientists have also exploited their knowledge of microbes to produce biotechnologically important enzymes such as Taq polymerase, reporter genes for use in other genetic systems and novel molecular biology techniques such as the yeast two-hybrid system.

See also

• Archaea
• Bacterium
• Biochemistry
• Eukaryote
• Fungus
• Genetics
• Geomicrobiology
• Immunology
• Medicine
• Prokaryote
• Virology
• Mycology

• Important publications in microbiology

Adapted from the Wikipedia article "Microbiology", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki