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[[Image:Agar plate with colonies.jpg|thumb|250px|right|An [[agar plate]] streaked with [[microorganism]]s]]
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'''Microbiology''' is the study of ''[[microorganisms]]'', which are [[unicellular]] or multi-cellular  [[microscopic]] [[organism]]s and [[community|communities]]. This includes [[eukaryote]]s (with a [[cell nucleus|nucleus]]) such as [[fungi]] and [[protists]] ([[protozoa]]), and [[prokaryote]]s (without a nucleus) such as [[bacteria]] and [[virus]]es (though viruses are usually classified differently to cellular living organisms).
[[Image:Ecoli_microcolonyPLoSBiologysm.jpg|left|frame|A growing microcolony of ''[[Escherichia coli]]'' From: Aging and Death in ''E. coli'' PLoS Biology Vol. 3, No. 2, e58 doi:10.1371/journal.pbio.0030058]]
 
'''Microbiology''' is the study of ''[[microorganisms]]'', which are [[unicellular]] or multi-cellular  [[microscopic]] [[organism]]s and [[community|communities]]. This includes [[eukaryote]]s (with a [[cell nucleus|nucleus]]) such as [[Fungus|fungi]] and [[protists]] ([[protozoa]]), and [[prokaryote]]s (without a nucleus) such as [[bacteria]] and [[virus]]es (though viruses are usually classified differently to cellular living organisms).


Although much is now known in the field of microbiology, advances are being made regularly. 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]], and new or emerging diseases such as [[HIV]] continually change the landscape of infectious disease.
Although much is now known in the field of microbiology, advances are being made regularly. 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]], and new or emerging diseases such as [[HIV]] continually change the landscape of infectious disease.


==History==
==History==
[[Bacteria]] were first observed by [[Anton van Leeuwenhoek]] in [[1676]] using a single-lens microscope of his own design.  The name "bacterium" was introduced much later, by [[Christian Gottfried Ehrenberg|Ehrenberg]] in [[1828]], derived from the [[Greek word]]  βακτηριον meaning "small stick".  While [[Antony van Leeuwenhoek]] is often cited as the first [[microbiologist]], the first recorded microbiological observation, that of the fruiting bodies of molds, was made earlier in [[1665]] by [[Robert Hooke]].
[[Bacteria]] were first observed by [[Antonie van Leeuwenhoek]] in 1676 using a single-lens microscope of his own design.  The name "bacterium" was introduced much later, by [[Christian Gottfried Ehrenberg|Ehrenberg]] in 1828, derived from the [[Greek word]]  βακτηριον meaning "small stick".  While [[Antonie van Leeuwenhoek]] is often cited as the first [[microbiologist]], the first recorded microbiological observation, that of the fruiting bodies of molds, was made earlier in 1665 by [[Robert Hooke]].


The field of '''bacteriology''' (later a subdiscipline of microbiology) is generally considered to have been founded by [[Ferdinand Cohn]] ([[1828]]-[[1898]]), a botanist whose studies on algae and photosynthetic bacteria led him to describe several bacteria including ''[[Bacillus]]'' and ''[[Beggiatoa]]''.  Ferdinand Cohn was also the first to formulate a scheme for the taxonomic classification of bacteria.
The field of '''bacteriology''' (later a subdiscipline of microbiology) is generally considered to have been founded by [[Ferdinand Cohn]] (1828-1898), a botanist whose studies on algae and photosynthetic bacteria led him to describe several bacteria including ''[[Bacillus]]'' and ''[[Beggiatoa]]''.  Ferdinand Cohn was also the first to formulate a scheme for the taxonomic classification of bacteria.


[[Louis Pasteur]] ([[1822]]-[[1895]]) and [[Robert Koch]] ([[1843]]-[[1910]]) were contemporaries of Cohn’s and are often considered to be the founders of '''medical microbiology'''. Pasteur is most famous for his series of experiments designed to disprove the then widely held [[theory of spontaneous generation]], thereby solidifying microbiology’s identity as a biological science.  Pasteur also designed methods for food preservation ([[pasteurization]]) and vaccines against several diseases such as [[anthrax]], fowl cholera and [[rabies]].  Robert Koch is best known for his contributions to the [[germ theory of disease]], proving that specific diseases were caused by specific pathogenic microorganisms. He developed a series of criteria that have become known as the [[Koch's postulates]].  Koch was one of the first scientists to focus on the isolation of bacteria in [[pure culture]] resulting in his description of several novel bacteria including ''[[Mycobacterium tuberculosis]]'', the causative agent of [[tuberculosis]].
[[Louis Pasteur]] (1822-1895) and [[Robert Koch]] (1843-1910) were contemporaries of Cohn’s and are often considered to be the founders of '''medical microbiology'''. Pasteur is most famous for his series of experiments designed to disprove the then widely held [[theory of spontaneous generation]], thereby solidifying microbiology’s identity as a biological science.  Pasteur also designed methods for food preservation ([[pasteurization]]) and vaccines against several diseases such as [[anthrax]], fowl cholera and [[rabies]].  Robert Koch is best known for his contributions to the [[germ theory of disease]], proving that specific diseases were caused by specific pathogenic microorganisms. He developed a series of criteria that have become known as the [[Koch's postulates]].  Koch was one of the first scientists to focus on the isolation of bacteria in [[pure culture]] resulting in his description of several novel bacteria including ''[[Mycobacterium tuberculosis]]'', the causative agent of [[tuberculosis]].


While Louis Pasteur and Robert Koch are often considered the founders of microbiology, their work did not accurately reflect the true diversity of the microbial world because of their almost exclusive focus on microorganisms having medical relevance.  It was not until the work of [[Martinus Beijerinck]] ([[1851]]-[[1931]]) and [[Sergei Winogradsky]] ([[1856]]-[[1953]]), the founders of '''general microbiology''' (an older term encompassing aspects of microbial physiology, diversity and ecology), that the true breadth of microbiology was revealed.  Martinus Beijerinck made two major contributions to microbiology: the discovery of [[virus]]es and the development of enrichment culture techniques.  While his work on the [[Tobacco Mosaic Virus]] established the basic principles of virology, it was his development of [[enrichment culturing]] <!-- should this be [[Growth medium]] or [[Microbiological culture]] ? --> that had the most immediate impact on microbiology by allowing for the cultivation of a wide range of microbes with wildly different physiologies.  Sergei Winogradsky was the first to develop the concept of [[chemolithotrophy]] and to thereby reveal the essential role played by microorganisms in geochemical processes. He was responsible for the first isolation and description of both nitrifying and nitrogen-fixing bacteria.
While Louis Pasteur and Robert Koch are often considered the founders of microbiology, their work did not accurately reflect the true diversity of the microbial world because of their almost exclusive focus on microorganisms having medical relevance.  It was not until the work of [[Martinus Beijerinck]] (1851-1931) and [[Sergei Winogradsky]] (1856-1953), the founders of '''general microbiology''' (an older term encompassing aspects of microbial physiology, diversity and ecology), that the true breadth of microbiology was revealed.  Martinus Beijerinck made two major contributions to microbiology: the discovery of [[virus]]es and the development of enrichment culture techniques.  While his work on the [[Tobacco Mosaic Virus]] established the basic principles of virology, it was his development of [[enrichment culturing]] <!-- should this be [[Growth medium]] or [[Microbiological culture]] ? --> that had the most immediate impact on microbiology by allowing for the cultivation of a wide range of microbes with wildly different physiologies.  Sergei Winogradsky was the first to develop the concept of [[chemolithotrophy]] and to thereby reveal the essential role played by microorganisms in geochemical processes. He was responsible for the first isolation and description of both nitrifying and nitrogen-fixing bacteria.


==Types of microbiology==
==Types of microbiology==
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*'''[[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]].
*'''[[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]].
*'''[[Microbial cell and population biology]]'''. The study of the cell biology of microorganisms, microbial interactions, signalling and evolutionary adaptations, multicellular-microorganisms and communities such as biofilms <ref> *{{cite book | author = Shapiro, James; and Dworkin, Martin| title = Bacteria as Multicellular Organisms | edition = 1st ed. | publisher = Oxford, Oxford and New York | year = 1997 | id = ISBN 0-19-509159-0 }}</ref>
*'''[[Microbial cell and population biology]]'''. The study of the cell biology of microorganisms, microbial interactions, signalling and evolutionary adaptations, multicellular-microorganisms and communities such as biofilms <ref> *{{cite book | author = Shapiro, James; and Dworkin, Martin| title = Bacteria as Multicellular Organisms | edition = 1st ed. | publisher = Oxford, Oxford and New York | year = 1997 | id = ISBN 0-19-509159-0 }}</ref>
*'''[[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]].
*'''[[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.
*'''[[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 cycle|nutrient cycling]], [[geomicrobiology]], microbial diversity and [[bioremediation]]<ref>[http://water.usgs.gov/wid/html/bioremed.html Bioremediation: Nature's Way to a Cleaner Environment]</ref>. Characterisation of key bacterial habitats such as the [[rhizosphere]] and [[phyllosphere]].
*'''[[Environmental microbiology]]''': The study of the function and diversity of microbes in their natural environments. Includes the study of [[microbial ecology]], microbially-mediated [[nutrient cycle|nutrient cycling]], [[geomicrobiology]], microbial diversity and [[bioremediation]]<ref>[http://water.usgs.gov/wid/html/bioremed.html Bioremediation: Nature's Way to a Cleaner Environment]</ref>. Characterisation of key bacterial habitats such as the [[rhizosphere]] and [[phyllosphere]].
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<!--These traits allowed Joshua and Esther Lederberg to devise an elegant experiment in [[1951]] demonstrating that adaptive mutations arise from [[preadaptation]] rather than directed mutation. For this purpose, they invented [[replica plating]], which allowed them to transfer numerous [[colony (biology)|bacterial colonies]] from their specific locations on one agar-filled petri dish to analogous locations on several other petri dishes. After replicating a plate of ''E. coli'', they exposed each of the new plates to a [[bacteriophage]] (also called phage). They observed that phage-resistant colonies were present at analogous locations on each of the plates, allowing them to conclude that the phage resistance trait had existed in the original colony, which had never been exposed to phage, instead of arising after the bacteria had been exposed to the virus.  !-- This was on the page before I modified it to read more like a general description of the field of microbiology, but it just didn't seem to make sense with the rest of the page the way I wrote it. I didn't want to just throw it out, but I don't know what to do with it now! Any suggestions?  transfer to [[genetics]]-->
<!--These traits allowed Joshua and Esther Lederberg to devise an elegant experiment in 1951 demonstrating that adaptive mutations arise from [[preadaptation]] rather than directed mutation. For this purpose, they invented [[replica plating]], which allowed them to transfer numerous [[colony (biology)|bacterial colonies]] from their specific locations on one agar-filled petri dish to analogous locations on several other petri dishes. After replicating a plate of ''E. coli'', they exposed each of the new plates to a [[bacteriophage]] (also called phage). They observed that phage-resistant colonies were present at analogous locations on each of the plates, allowing them to conclude that the phage resistance trait had existed in the original colony, which had never been exposed to phage, instead of arising after the bacteria had been exposed to the virus.  !-- This was on the page before I modified it to read more like a general description of the field of microbiology, but it just didn't seem to make sense with the rest of the page the way I wrote it. I didn't want to just throw it out, but I don't know what to do with it now! Any suggestions?  transfer to [[genetics]]-->


==References==
==References==
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* [http://www.rowland.org/labs/bacteria/showmovie.php?mov=swimming_ecoli Movies of growing bacteria.]
* [http://www.rowland.org/labs/bacteria/showmovie.php?mov=swimming_ecoli Movies of growing bacteria.]
* [http://www.learner.org/channel/courses/biology/units/microb/index.html Microbial diversity]
* [http://www.learner.org/channel/courses/biology/units/microb/index.html Microbial diversity]
* [http://www.learner.org/channel/courses/biology/textbook/infect/index.html Emerging infectious diseases]
* [http://www.learner.org/channel/courses/biology/textbook/infect/index.html Emerging infectious diseases][[Category:Suggestion Bot Tag]]
 
{{Biology-footer}}
 
[[Category:Biology]]
[[Category:Microbiology|*]]
[[Category:CZ Live]]
[[Category:Biology Workgroup (Top)]]

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A growing microcolony of Escherichia coli From: Aging and Death in E. coli PLoS Biology Vol. 3, No. 2, e58 doi:10.1371/journal.pbio.0030058

Microbiology is the study of microorganisms, which are unicellular or multi-cellular microscopic organisms and communities. This includes eukaryotes (with a nucleus) such as fungi and protists (protozoa), and prokaryotes (without a nucleus) such as bacteria and viruses (though viruses are usually classified differently to cellular living organisms).

Although much is now known in the field of microbiology, advances are being made regularly. 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, and new or emerging diseases such as HIV continually change the landscape of infectious disease.

History

Bacteria were first observed by Antonie van Leeuwenhoek in 1676 using a single-lens microscope of his own design. The name "bacterium" was introduced much later, by Ehrenberg in 1828, derived from the Greek word βακτηριον meaning "small stick". While Antonie van Leeuwenhoek is often cited as the first microbiologist, the first recorded microbiological observation, that of the fruiting bodies of molds, was made earlier in 1665 by Robert Hooke.

The field of bacteriology (later a subdiscipline of microbiology) is generally considered to have been founded by Ferdinand Cohn (1828-1898), a botanist whose studies on algae and photosynthetic bacteria led him to describe several bacteria including Bacillus and Beggiatoa. Ferdinand Cohn was also the first to formulate a scheme for the taxonomic classification of bacteria.

Louis Pasteur (1822-1895) and Robert Koch (1843-1910) were contemporaries of Cohn’s and are often considered to be the founders of medical microbiology. Pasteur is most famous for his series of experiments designed to disprove the then widely held theory of spontaneous generation, thereby solidifying microbiology’s identity as a biological science. Pasteur also designed methods for food preservation (pasteurization) and vaccines against several diseases such as anthrax, fowl cholera and rabies. Robert Koch is best known for his contributions to the germ theory of disease, proving that specific diseases were caused by specific pathogenic microorganisms. He developed a series of criteria that have become known as the Koch's postulates. Koch was one of the first scientists to focus on the isolation of bacteria in pure culture resulting in his description of several novel bacteria including Mycobacterium tuberculosis, the causative agent of tuberculosis.

While Louis Pasteur and Robert Koch are often considered the founders of microbiology, their work did not accurately reflect the true diversity of the microbial world because of their almost exclusive focus on microorganisms having medical relevance. It was not until the work of Martinus Beijerinck (1851-1931) and Sergei Winogradsky (1856-1953), the founders of general microbiology (an older term encompassing aspects of microbial physiology, diversity and ecology), that the true breadth of microbiology was revealed. Martinus Beijerinck made two major contributions to microbiology: the discovery of viruses and the development of enrichment culture techniques. While his work on the Tobacco Mosaic Virus established the basic principles of virology, it was his development of enrichment culturing that had the most immediate impact on microbiology by allowing for the cultivation of a wide range of microbes with wildly different physiologies. Sergei Winogradsky was the first to develop the concept of chemolithotrophy and to thereby reveal the essential role played by microorganisms in geochemical processes. He was responsible for the first isolation and description of both nitrifying and nitrogen-fixing bacteria.

Types of microbiology

The field of microbiology can be divided into several subtimes overlapping subdisciplines:

Fermenting tanks with yeast being used to brew beer

Benefits of microbiology

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, vitamins and dairy products), antibiotic production and as standard laboratory tools for genetic manipulation of higher organisms such as plants. Scientists have 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. Microbes play vital roles in geochemical cycles such as the Nitrogen-cycle.


References

  1. ↑ *Shapiro, James; and Dworkin, Martin (1997). Bacteria as Multicellular Organisms, 1st ed.. Oxford, Oxford and New York. ISBN 0-19-509159-0. 
  2. ↑ Bioremediation: Nature's Way to a Cleaner Environment

Further reading

  • Krasner, Robert I. (2002). The Microbial Challenge: Human-Microbe Interactions, 1st.. ASM Press, Washington, DC. ISBN 0-13-144329-4. 
  • Madigan, Michael; Martinko, John (editors) (2005). Brock Biology of Microorganisms, 11th ed.. Prentice Hall. ISBN 1-55581-241-1. 
  • Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology, 4th ed.. McGraw Hill. ISBN 0-8385-8529-9. 
  • Schaechter, Moselio; Ingraham, John L; Neidhardt, Frederick C (2006). Microbe, 1st ed.. ASM Press. ISBN 1-55581-320-8. 

See also

External links

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