Microbiology 19909 226134634 2008-07-16T23:43:03Z ClueBot 4928500 Reverting possible vandalism by [[Special:Contributions/67.84.108.252|67.84.108.252]] to version by ST47. False positive? [[User:ClueBot/FalsePositives|Report it]]. Thanks, [[User:ClueBot]]. (441989) (Bot) [[Image:Agar plate with colonies.jpg|thumb|right|An [[agar plate]] streaked with [[microorganism]]s]] '''Microbiology''' is the study of ''[[microorganisms]]'', which are [[unicellular]] or cell-cluster [[microscopic]] [[organism]]s.<ref name=Brock>{{cite book | author = Madigan M, Martinko J (editors) | title = Brock Biology of Microorganisms | edition = 11th ed. | publisher = Prentice Hall | year = 2006 | isbn = 0-13-144329-1 }}</ref> This includes [[eukaryote]]s such as [[fungi]] and [[protists]], and [[prokaryote]]s, which are [[bacteria]] and [[archaea]]. [[Virus]]es, though not strictly classed as living organisms, are also studied.<ref>{{cite web | author = Rice G | title = Are Viruses Alive? | url = http://serc.carleton.edu/microbelife/yellowstone/viruslive.html | date = 2007-03-27 |accessdate = 2007-07-23}}</ref> In short; microbiology refers to the study of life and organisms that are too small to be seen with the naked eye. Microbiology is a broad term which includes [[virology]], [[mycology]], [[parasitology]] and other branches. A [[microbiologist]] is a specialist in microbiology. Microbiology is researched actively, and the field is advancing continually. We have probably only studied about one percent of all of the microbe species on Earth.<ref name="Amann1995">{{cite journal | author = Amann RI, Ludwig W, Schleifer KH | year = 1995 | title = Phylogenetic identification and in situ detection of individual microbial cells without cultivation | journal = Microbiol. Rev. | volume = 59 | pages = 143–169 | url = http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=7535888}}</ref> Although microbes were first observed over three hundred years ago, the field of microbiology can be said to be in its infancy relative to older biological disciplines such as [[zoology]] and [[botany]]. ==History== ===Pre-microbiology=== The existence of [[microorganisms]] was hypothesized for many centuries before their actual discovery in the 17th century. The first theories on microorganisms was made by [[Ancient Rome|Roman]] [[scholar]] [[Marcus Terentius Varro]] in a book titled ''On Agriculture'' in which he warns against locating a homestead in the vicinity of swamps: {{cquote|...and because there are bred certain minute creatures which cannot be seen by the eyes, which float in the air and enter the body through the mouth and nose and there cause serious diseases.<ref>''Varro On Agriculture'' 1,xii Loeb</ref>}} This passage seems to indicate that the ancients were aware of the possibility that diseases could be spread by yet unseen organisms. In ''[[The Canon of Medicine]]'' (1020), [[Abū Alī ibn Sīnā]] (Avicenna) stated that bodily [[secretion]] is contaminated by foul foreign earthly bodies before being infected.<ref name=Syed>Ibrahim B. Syed, Ph.D. (2002). "Islamic Medicine: 1000 years ahead of its times", ''[[The Islamic Medical Association of North America|Journal of the Islamic Medical Association]]'' '''2''', p. 2-9.</ref> He also hypothesized on the contagious nature of [[tuberculosis]] and other [[infectious disease]]s, and used [[quarantine]] as a means of limiting the spread of contagious diseases.<ref>David W. Tschanz, MSPH, PhD (August 2003). "Arab Roots of European Medicine", ''Heart Views'' '''4''' (2).</ref> When the [[Black Death]] [[bubonic plague]] reached [[al-Andalus]] in the 14th century, Ibn Khatima hypothesized that infectious diseases are caused by "[[Microorganisms|minute bodies]]" which enter the human body and cause disease.<ref name=Syed/> In 1546 [[Girolamo Fracastoro]] proposed that [[epidemic]] [[diseases]] were caused by transferable seedlike entities that could transmit infection by direct or indirect contact or even without contact over long distances. All these early claims about the existence of microorganisms were [[speculative]] in nature and not based on any data or science. Microorganisms were neither proven, observed, and correctly and accurately described until the 17th century. The reason for this was that all these early inquiries lacked the most fundamental tool in order for microbiology and [[bacteriology]] to exist as a science, and that was the [[microscope]]. [[Image:Antoni van Leeuwenhoek.png|thumb|240px|right|[[Antonie van Leeuwenhoek]], the first [[microbiologist]] and the first to observe microorganisms using a microscope and is called as the 'Father of Microbiology'and the first person to invent Microscope.]] ===Discovery and origins of microbiology=== [[Bacteria]] and [[microorganisms]] were first observed by [[Antonie van Leeuwenhoek]] in 1676 using a single-lens microscope of his own design. In doing so [[Leeuwenhoek]] made one of the most important discoveries in [[biology]] and initiated the scientific fields of [[bacteriology]] and microbiology.<ref name=Brock /> The name "bacterium" was introduced much later, by [[Christian Gottfried Ehrenberg|Ehrenberg]] in [[1828]], derived from the [[Greek language|Greek]] ''βακτηριον'' meaning "small stick". While Van Leeuwenhoek is often cited as the first [[microbiologist]], the first recorded microbiological observation, that of the fruiting bodies of [[mold]]s, was made earlier in 1665 by [[Robert Hooke]].<ref>{{cite journal |author=Gest H |title=The remarkable vision of Robert Hooke (1635-1703): first observer of the microbial world |journal=Perspect. Biol. Med. |volume=48 |issue=2 |pages=266–72 |year=2005 |pmid=15834198 |doi=10.1353/pbm.2005.0053}}</ref> 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 [[Phototroph|photosynthetic bacteria]] led him to describe several bacteria including ''[[Bacillus]]'' and ''[[Beggiatoa]]''. Cohn was also the first to formulate a scheme for the [[taxonomic classification]] of bacteria.<ref>{{cite journal |author=Drews G |title=Ferdinand Cohn, a Founder of Modern Microbiology |journal=ASM News |volume=65 |issue=8 |pages= |year=1999 |url=http://www.asm.org/Articles/Ferdinand.html}}</ref> [[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]]'''.<ref name=Sherris>{{cite book | author = Ryan KJ, Ray CG (editors) | title = Sherris Medical Microbiology | edition = 4th ed. | publisher = McGraw Hill | year = 2004 | isbn = 0-8385-8529-9 }}</ref> 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.<ref>{{cite journal |author=Bordenave G |title=Louis Pasteur (1822-1895) |journal=Microbes Infect. |volume=5 |issue=6 |pages=553–60 |year=2003 |pmid=12758285 |doi=}}</ref> Pasteur also designed methods for food preservation ([[pasteurization]]) and vaccines against several diseases such as [[anthrax]], fowl cholera and [[rabies]].<ref name=Brock /> 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]].<ref name=Brock /> While Pasteur and Koch are often considered the founders of microbiology, their work did not accurately reflect the true diversity of the microbial world because of their exclusive focus on microorganisms having direct 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.<ref name=Brock /> Beijerinck made two major contributions to microbiology: the discovery of [[virus]]es and the development of enrichment culture techniques.<ref>{{cite web | author = Johnson J | title = Martinus Willem Beijerinck | publisher = American Phytopathological Society | url = http://www.apsnet.org/Education/feature/TMV/intro.html | date = 1998-07-01 | accessdate = 2007-07-23}}</ref> While his work on the [[Tobacco Mosaic Virus]] established the basic principles of virology, it was his development of [[enrichment culture|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. Winogradsky was the first to develop the concept of [[chemolithotrophy]] and to thereby reveal the essential role played by microorganisms in geochemical processes.<ref>{{cite web | author = Paustian T, Roberts G | title = Beijerinck and Winogradsky initiate the field of environmental microbiology | work = The Microbial World | url = http://www.microbiologytext.com/index.php?module=Book&func=displayarticle&art_id=32| accessdate = 2007-07-23}}</ref> He was responsible for the first isolation and description of both [[nitrifying bacteria|nitrifying]] and [[nitrogen-fixing bacteria]].<ref name=Brock /> ==Types== The field of microbiology can be generally divided into several subdisciplines: *'''[[Microbial physiology]]''': The study of how the microbial cell functions biochemically. Includes the study of microbial growth, microbial [[metabolism]] and [[bacterial cell structure|microbial cell structure]]. *'''[[Microbial genetics]]''': The study of how [[gene]]s 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]] or animal [[taxonomy]]. *'''[[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]]. Characterisation of key bacterial habitats such as the [[rhizosphere]] and [[phyllosphere]], [[soil]] and [[groundwater]] [[ecosystem]]s, open [[oceans]] or extreme environments ([[extremophile]]s). *'''[[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. This field also includes [[brewing]], an important application of microbiology. *'''[[Aeromicrobiology]]''': The study of airborne microorganisms. *'''[[Food microbiology]]''': The study of microorganisms causing food spoilage. *'''[[Pharmaceutical microbiology]]''': the study of microorganisms causing pharmaceutical contamination and spoilage. *'''[[Oral microbiology]]''': the study of microorganisms of the mouth in particular those causing [[caries]] and [[periodontal disease]]. ==Benefits== [[Image:Samadams2.jpg|thumb|right|Fermenting tanks with [[yeast]] being used to [[Brewing|brew]] [[beer]] ]] {{refimprovesect|date=July 2007}} 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 organisms such as plants. Scientists have also exploited their knowledge of microbes to produce biotechnologically important [[enzyme]]s such as [[Taq polymerase]], [[reporter gene]]s for use in other genetic systems and novel molecular biology techniques such as the [[two-hybrid screening|yeast two-hybrid system]]. Bacteria can be used for the industrial production of [[amino acid]]s. ''Corynebacterium glutamicum'' is one of the most important bacterial species with an annual production of more than two million tons of amino acids, mainly L-glutamate and L-lysine. <ref name= BurkovskiA>{{cite book | author = Burkovski A (editor). | title = Corynebacteria: Genomics and Molecular Biology | publisher = Caister Academic Press | year = 2008 | url=http://www.horizonpress.com/cory | id = [http://www.horizonpress.com/cory ISBN 978-1-904455-30-1 ]}}</ref> A variety of [[biopolymer]]s, such as [[polysaccharide]]s, [[polyester]]s, and [[polyamide]]s, are produced by microorganisms. Microorganisms are used for the biotechnological production of biopolymers with tailored properties suitable for high-value medical application such as tissue engineering and drug delivery. Microorganisms are used for the biosynthesis of [[xanthan]], [[alginate]], [[cellulose]], [[cyanophycin]], poly(gamma-glutamic acid), [[levan]], [[hyaluronic acid]], organic acids, [[oligosaccharide]]s and [[polysaccharide]], and polyhydroxyalkanoates.<ref name= RehmBHA>{{cite book | author = Rehm BHA (editor). | title = Microbial Production of Biopolymers and Polymer Precursors: Applications and Perspectives | publisher = Caister Academic Press | year = 2008 | url=http://www.horizonpress.com/biopolymers | id = [http://www.horizonpress.com/biopolymers ISBN 978-1-904455-36-3 ]}}</ref> Microorganisms are beneficial for [[microbial biodegradation]] or [[bioremediation]] of domestic, agricultural and industrial wastes and subsurface [[pollution]] in soils, sediments and marine environments. The ability of each microorganism to degrade [[toxic waste]] depends on the nature of each [[contaminant]]. Since most sites are typically comprised of multiple pollutant types, the most effective approach to [[microbial biodegradation]] is to use a mixture of bacterial species and strains, each specific to the [[biodegradation]] of one or more types of contaminants.<ref name=Diaz>{{cite book | author = Diaz E (editor). | title = Microbial Biodegradation: Genomics and Molecular Biology | edition = 1st ed. | publisher = Caister Academic Press | year = 2008 | url=http://www.horizonpress.com/biod | id = [http://www.horizonpress.com/biod ISBN 978-1-904455-17-2]}}</ref> There are also various claims concerning the contributions to human and animal health by consuming [[probiotics]] (bacteria potentially beneficial to the digestive system) and/or [[prebiotics]] (substances consumed to promote the growth of probiotic microorganisms).<ref name=Tannockpro3>{{cite book | author = Tannock GW (editor). | title = Probiotics and Prebiotics: Scientific Aspects | publisher = Caister Academic Press | year = 2005 | url=http://www.horizonpress.com/pro3 | id = [http://www.horizonpress.com/pro3 ISBN 978-1-904455-01-1]}}</ref> <!--These traits allowed Joshua and Esther Lederberg to devise an elegant experiment in [[1951]] demonstrating that [[adaptive mutation]]s 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? --> <br clear=all /> ==References== <!-- --------------------------------------------------------------- See http://en.wikipedia.org/wiki/Wikipedia:Footnotes for a discussion of different citation methods and how to generate footnotes using the <ref> & </ref> tags and the {{Reflist}} template -------------------------------------------------------------------- --> {{Reflist|2}} ===Further reading=== <div class="references-small"> * {{cite book | author = Lerner, Brenda Wilmoth & K. Lee Lerner (eds) | title = Medicine, health, and bioethics : essential primary sources | edition = 1st ed. | publisher = Thomson Gale | year = 2006 | id = ISBN 1414406231 }} * {{cite book | author = Witzany, Guenther | title = Bio-Communication of Bacteria and its Evolutionary Interrelations to Natural Genome Editing Competences of Viruses. | publisher = Nature Precedings | year = 2008 | id = hdl:10101/npre.2008.1738.1 }} </div> == See also == {{MultiCol}} * [[Archaea]] * [[Bacteria]] * [[Biochemistry]] * [[Biomilling]] * [[Biosafety]] * [[Biotechnology]] * [[Environmental microbiology]] * [[Eukaryote]] {{ColBreak}} * [[Food microbiology]] * [[Genetics]] * [[Geomicrobiology]] * [[Good Hygiene Practice]] * [[Good Microbiological Practice]] * [[Immunology]] * [[List of publications in biology#Microbiology|Important publications in microbiology]] * [[Industrial microbiology]] {{ColBreak}} * [[Medical technologist]] * [[Medicine]] * [[Mycology]] * [[Oral microbiology]] * [[Phage meetings|Bacteriophage meetings]] * [[Prokaryote]] * [[Virology]] {{EndMultiCol}} ==External links== {{WVD}} ===General=== * [http://media.med.sc.edu/microbiology2007/ Online lectures in microbiology] University of South Carolina * [http://www.microbiologytext.com/index.php?module=Book&func=toc&book_id=4 Online Microbiology textbook] * [http://www.textbookofbacteriology.net/ Todar's Bacteriology textbook] * [http://pathmicro.med.sc.edu/book/welcome.htm Online Medical Microbiology textbook] ===Journals=== * [[Critical Reviews in Microbiology]] ([http://www.informaworld.com/crmicrobiology journal home]) * [[Nature Reviews Microbiology]] ([http://www.nature.com/nrmicro/index.html journal home]) * [[Springer Protocols]] in Microbiology ===Professional organizations=== * [http://www.microbiologystudents.com/ Information portal For Microbiology Students] * [http://www.asm.org/ American Society for Microbiology] * [http://www.socgenmicrobiol.org.uk/ Society for General Microbiology] * [http://www.simhq.org/ Society for Industrial Microbiology] {{Biology-footer}} [[Category:Microbiology| ]] [[Category:Subjects taught in medical school]] {{Link FA|fo}} [[af:Mikrobiologie]] [[an:Microbiolochía]] [[ar:علم الأحياء الدقيقة]] [[ast:Microbioloxía]] [[bg:Микробиология]] [[ca:Microbiologia]] [[cs:Mikrobiologie]] [[da:Mikrobiologi]] [[de:Mikrobiologie]] [[el:Μικροβιολογία]] [[eo:Mikrobiologio]] [[es:Microbiología]] [[eu:Mikrobiologia]] [[fi:Mikrobiologia]] [[fo:Smáverulívfrøði]] [[fr:Microbiologie]] [[ga:Micribhitheolaíocht]] [[he:מיקרוביולוגיה]] [[hr:Mikrobiologija]] [[id:Mikrobiologi]] [[ilo:Microbiolohia]] [[it:Microbiologia]] [[ja:微生物学]] [[ko:미생물학]] [[ku:Hûrjînewerzanist]] [[la:Microbiologia]] [[lt:Mikrobiologija]] [[lv:Mikrobioloģija]] [[mk:Микробиологија]] [[nl:Microbiologie]] [[no:Mikrobiologi]] [[oc:Microbiologia]] [[pl:Mikrobiologia]] [[pt:Microbiologia]] [[qu:Mikru Kawsay Yachay]] [[ro:Microbiologie]] [[ru:Микробиология]] [[simple:Microbiology]] [[sl:Mikrobiologija]] [[sq:Mikrobiologjia]] [[sr:Микробиологија]] [[su:Mikrobiologi]] [[sv:Mikrobiologi]] [[th:จุลชีววิทยา]] [[tl:Mikrobiyolohiya]] [[tr:Mikrobiyoloji]] [[uk:Мікробіологія]] [[vi:Vi sinh vật học]] [[zh:微生物学]]