This article or section needs copy editing for grammar, style, cohesion, tone and/or spelling. You can assist by editing it now. A how-to guide is available, as is general documentation. This article has been tagged since January 2007.

An Agar Plate -- an example of a bacterial growth medium. Specifically, it is a streak plate; the bacterial colonies are the orange lines and ovals.

A growth medium or culture medium is a substance in which microorganisms or cells can grow.^[1] There are different types of media for growing different types of cells.^[2] Image File history File links Acap. ... Image File history File links An agar plate with microorganisms isolated from a deep-water sponge. ... Image File history File links An agar plate with microorganisms isolated from a deep-water sponge. ... A cluster of Escherichia coli bacteria magnified 10,000 times. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell being used to describe the smallest unit of a living organism Cells in culture, stained for keratin (red) and DNA (green) The cell is the... Growth can mean increase in spatial number or complexity for concrete entities in time or increase in some other dimension for abstract or hard-to-measure entities. ...

There are two major types of growth media: those used for cell culture – which use specific cell types derived from plants or animals, and microbiological culture used for growing microorganisms, such as bacteria or yeast. The most common growth media for microorganisms are nutrient broths and agar plates; specialized media are sometimes required for microorganism and cell culture growth.^[1] Some organisms, termed fastidious organisms, require specialized environments due to complex nutritional requirements. Viruses, for example, are obligatory intracellular parasites and require a growth medium composed of living cells. Epithelial cells in culture, stained for keratin (red) and DNA (green) Cell culture is the process by which either prokaryotic or eukaryotic cells are grown under controlled conditions. ... A microbiological culture is a way to determine the cause of infectious disease by letting the agent multiply (reproduce) in predetermined media. ... Phyla Actinobacteria Aquificae Chlamydiae Bacteroidetes/Chlorobi Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Lentisphaerae Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Verrucomicrobia Bacteria (singular: bacterium) are unicellular microorganisms. ... Typical divisions Ascomycota (sac fungi) Saccharomycotina (true yeasts) Taphrinomycotina Schizosaccharomycetes (fission yeasts) Basidiomycota (club fungi) Urediniomycetes Sporidiales Yeasts are a growth form of eukaryotic microorganisms classified in the kingdom Fungi, with approximately 1,500 species described. ... An agar plate streaked with microorganisms isolated from a deep-water sponge. ... A parasite is an organism that spends a significant portion of its life in or on the living tissue of a host organism and which causes harm to the host without immediately killing it. ...

Types of growth media

The most common growth media for microorganisms are nutrient broths (liquid nutrient medium) or Lysogeny broth (L-B medium). Liquid mediums are often mixed with agar and poured into petri dishes to solidfy. These agar plates provide a solid medium on which microbes may be cultured. Bacteria grown in liquid cultures often form colloidal suspensions. Lysogeny broth (LB), a nutritionally rich medium, is primarily used for the growth of bacteria. ... This does not adequately cite its references or sources. ... Man looking at fungus inside of petri dishes A Petri dish is a shallow glass or plastic cylindrical dish that biologists use to culture microbes. ... An agar plate streaked with microorganisms isolated from a deep-water sponge. ... In general, a colloid or colloidal dispersion is a substance with components of one or two phases, a type of mixture intermediate between a homogeneous mixture (also called a solution) and a heterogeneous mixture with properties also intermediate between the two. ... It has been suggested that this article or section be merged into Mixture. ...

The differences between growth media used for cell culture and those used for microbiological culture are due to the fact that cells derived from whole organisms and grown in culture often cannot grow without the addition of, for instance, hormones or growth factors which usually occur in vivo.^[3] In the case of animal cells, this difficulty is often addressed by the addition of blood serum to the medium. In the case of microorganisms, there are no such limitations, as they are often unicellular organisms. One other major difference is that animal cells in culture are often grown on a flat surface to which they attach, and the medium is provided in a liquid form, which covers the cells. In contrast, bacteria such as Escherichia coli may be grown on solid media or in liquid media. Hormone is also the NATO reporting name for the Soviet/Russian Kamov Ka-25 military helicopter. ... Growth factor is any of about twenty small proteins that attach to specific receptors on the surface of stem cells in bone marrow and promote differentiation and maturation of these cells into morphotic constituents of blood. ... In vivo (Latin for (with)in the living). ... Blood plasma is a component of blood. ... A microorganism or microbe is an organism that is so small that it is microscopic (invisible to the naked eye). ... E. coli redirects here. ...

An important distinction between growth media types is that of a defined versus undefined media.^[1] A defined medium will have known quantities of all ingredients. For microorganisms, they consist of providing trace elements and vitamins required by the microbe and especially a defined carbon source and nitrogen source. Glucose or glycerol are often used as carbon sources, and ammonium salts or nitrates as inorganic nitrogen sources). An undefined medium has some complex ingredients, such as yeast extract or casein hydrolysate, which consist of a mixture of many, many chemical species in unknown proportions. Undefined media are sometimes chosen based on price and sometimes by necessity - some microorganisms have never been cultured on defined media. General Name, symbol, number carbon, C, 6 Chemical series nonmetals Group, period, block 14, 2, p Appearance black (graphite) colorless (diamond) Standard atomic weight 12. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... Glucose (Glc), a monosaccharide (or simple sugar), is an important carbohydrate in biology. ... Glycerol is a chemical compound with the formula HOCH2CH(OH)CH2OH. This colorless, odorless, viscous liquid is widely used in pharmaceutical formulations. ... A ball-and-stick model of the ammonium cation Fumes from hydrochloric acid and ammonia forming a white cloud of ammonium chloride Ammonium is also an old name for the Siwa Oasis in western Egypt. ... For other uses, see Salt (disambiguation). ... An electrostatic potential map of the nitrate ion. ... Inorganic chemistry is the branch of chemistry concerned with the properties and reactions of inorganic compounds. ... Yeast extract is the common name for yeast autolysates, that is, concentrations of yeast cells that are allowed to die and break up, so that the yeasts digestive enzymes break their proteins down into simpler compounds. ...

A good example of a growth medium is the wort used to make beer. The wort contains all the nutrients required for yeast growth, and under anaerobic conditions, alcohol is produced. When the fermentation process is complete, the combination of medium and dormant microbes, now beer, is ready for consumption. The exterior of the WORT studio building. ... For other uses, see Beer (disambiguation). ... It has been suggested that Anoxic sea water, Oxygen minimum zone, and Hypoxic zone be merged into this article or section. ... For other uses, see Fermentation. ...

Nutrient media

Undefined media (also known as basal or complex media) is an undefined media that contains:

• a carbon source such as glucose for bacterial growth
• water
• various salts need for bacterial growth
• a source of amino acids and nitrogen (e.g., beef, yeast extract)

This is an undefined medium because the amino acid source contains a variety of compounds with the exact composition unknown. Nutrient media contain all the elements that most bacteria need for growth and are non-selective, so they are used for the general cultivation and maintenance of bacteria kept in laboratory culture collections. Glucose (Glc), a monosaccharide (or simple sugar), is an important carbohydrate in biology. ...

Defined media (also known as chemical defined media)

• all the chemicals used are known and
• does not contain any animal, yeast, plant tissue.

Differential medium

• some sort of indicator, typically a dye, is added , that allows for the differentiation of particular chemical reactions occurring during growth.

Minimal media

Minimal media are those that contain the minimum nutrients possible for colony growth, generally without the presence of amino acids, and are often used by microbiologists and geneticists to grow "wild type" microorganisms. Minimal medium can also be used to select for or against recombinants or exconjugants. Recombinant proteins are proteins that are produced by different genetically modified organisms following insertion of the relevant DNA into their genome. ...

Minimal medium typically contains:

• a carbon source for bacterial growth, which may be a sugar such as glucose, or a less energy-rich source like succinate
• various salts, which may vary among bacteria species and growing conditions; these generally provide essential elements such as magnesium, nitrogen, phosphorus, and sulfur to allow the bacteria to synthesize protein and nucleic acid
• water

Supplementary minimal media are a type of minimal media that also contains a single selected agent, usually an amino acid or a sugar. This supplementation allows for the culturing of specific lines of auxotrophic recombinants. Glucose (Glc), a monosaccharide (or simple sugar), is an important carbohydrate in biology. ... Succinate is the anion of succinic acid. ... General Name, symbol, number magnesium, Mg, 12 Chemical series alkaline earth metals Group, period, block 2, 3, s Appearance silvery white solid at room temp Standard atomic weight 24. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... General Name, Symbol, Number phosphorus, P, 15 Chemical series nonmetals Group, Period, Block 15, 3, p Appearance waxy white/ red/ black/ colorless Standard atomic weight 30. ... General Name, Symbol, Number sulfur, S, 16 Chemical series nonmetals Group, Period, Block 16, 3, p Appearance lemon yellow Standard atomic weight 32. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Look up nucleic acid in Wiktionary, the free dictionary. ... Phenylalanine is one of the standard amino acids. ... Magnification of grains of sugar, showing their monoclinic hemihedral crystalline structure. ... Auxotrophy is the inability of an organism to synthesize a particular organic compound required for its growth (as defined by IUPAC). ... Recombinant proteins are proteins that are produced by different genetically modified organisms following insertion of the relevant DNA into their genome. ...

Selective media

Blood-free, charcoal-based selective medium agar (CSM) for isolation of Campylobacter.

Blood agar plates are often used to diagnose infection. On the right is a positive Staphylococcus infection; on the left a positive Streptococcus culture.

Selective media are used for the growth of only select microorganisms. For example, if a microorganism is resistant to a certain antibiotic, such as ampicillin or tetracycline, then that antibiotic can be added to the medium in order to prevent other cells, which do not possess the resistance, from growing. Media lacking an amino acid such as proline in conjunction with E. coli unable to synthesize it were commonly used by geneticists before the emergence of genomics to map bacterial chromosomes. Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (2048 × 1536 pixel, file size: 334 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (2048 × 1536 pixel, file size: 334 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Species C. fetus C. jejuni Campylobacter is a genus of Gram-negative bacteria. ... Image File history File linksMetadata Size of this preview: 800 × 533 pixelsFull resolution (2700 × 1800 pixel, file size: 2. ... Image File history File linksMetadata Size of this preview: 800 × 533 pixelsFull resolution (2700 × 1800 pixel, file size: 2. ... Species S. aureus S. caprae S. epidermidis S. haemolyticus S. hominis S. lugdunensis S. saprophyticus S. warneri S. xylosus Staphylococcus (in Greek staphyle means bunch of grapes and coccos means granule) is a genus of Gram-positive bacteria. ... Streptococcus is a genus of spherical shaped Gram-positive bacteria, belonging to the phylum Firmicutes[1] and the lactic acid bacteria group. ... Staphylococcus aureus - Antibiotics test plate. ... Ampicillin is a beta-lactam antibiotic that has been used extensively to treat bacterial infections since 1961. ... Tetracycline (INN) (IPA: ) is a broad-spectrum antibiotic produced by the streptomyces bacterium, indicated for use against many bacterial infections. ... Phenylalanine is one of the standard amino acids. ... Proline is an α-amino acid with the chemical formula HO2CCH(NH[CH2)3]. L-Proline is one of the twenty DNA-encoded amino acids. ... E. coli redirects here. ... Genomics is the study of an organisms entire genome; Rathore et al, . Investigation of single genes, their functions and roles is something very common in todays medical and biological research, and cannot be said to be genomics but rather the most typical feature of molecular biology. ...

Selective growth media are also used in cell culture to ensure the survival or proliferation of cells with certain properties, such as antibiotic resistance or the ability to synthesize a certain metabolite. Normally, the presence of a specific gene or an allele of a gene confers upon the cell the ability to grow in the selective medium. In such cases, the gene is termed a marker. Epithelial cells in culture, stained for keratin (red) and DNA (green) Cell culture is the process by which either prokaryotic or eukaryotic cells are grown under controlled conditions. ... Antibiotic resistance is the ability of a micro-organism to withstand the effects of an antibiotic. ... A metabolite is the product of metabolism. ... For a non-technical introduction to the topic, see Introduction to Genetics. ... For the hard rock band, see Allele (band). ... A genetic marker is a known DNA sequences (e. ...

Selective growth media for eukaryotic cells commonly contain neomycin to select cells that have been successfully transfected with a plasmid carrying the neomycin resistance gene as a marker. Gancyclovir is an exception to the rule as it is used to specifically kill cells that carry its respective marker, the Herpes simplex virus thymidine kinase (HSV TK). Kingdoms Eukaryotes are organisms with complex cells, in which the genetic material is organized into membrane-bound nuclei. ... Neomycin is an aminoglycoside antibiotic that is found in many topical medications such as creams, ointments and eyedrops. ... Introducing DNA into eukaryotic cells, such as animal cells, is called transfection. ... Species Herpes simplex virus 1 (HSV-1) Herpes simplex virus 2 (HSV-2) This article is about the virus. ...

Four types of agar plates demonstrating differential growth depending on bacterial metabolism.

Some examples of selective media include: Image File history File links Download high resolution version (700x721, 41 KB) After 24 hours of growth, this image depicts four different agar media culture plates that had been inoculated with Shigella sp. ... Image File history File links Download high resolution version (700x721, 41 KB) After 24 hours of growth, this image depicts four different agar media culture plates that had been inoculated with Shigella sp. ...

• eosin-methylen blue agar (EMB) that contains methylene blue – toxic to Gram-positive bacteria, allowing only the growth of Gram negative bacteria
• YM (yeast and mold) which has a low pH, deterring bacterial growth
• blood agar (used in strep tests), which contains beef heart blood that becomes transparent in the presence of hemolytic Streptococcus
• MacConkey agar for Gram-negative bacteria
• Hektoen Enteric (HE) which is selective for Gram-negative bacteria
• Mannitol Salt Agar (MSA) which is selective for Gram-positive bacteria and differential for mannitol
• xylose lysine desoxyscholate (XLD), which is selective for Gram-negative bacteria
• Buffered charcoal yeast extract agar, which is selective for certain gram-negative bacteria, especially Legionella pneumophila

Methylene blue is a heterocyclic aromatic chemical compound with molecular formula: C16H18ClN3S. It has many uses in a range of different fields, such as biology or chemistry. ... Gram-positive bacteria are those that are stained dark blue or violet by gram staining, in contrast to gram-negative bacteria, which are not affected by the stain. ... Gram-negative Pseudomonas aeruginosa bacteria (pink-red rods). ... YM or Ym may refer to: YM (magazine), a U.S. magazine geared towards teenage girls the IATA code for Montenegro Airlines The Youth Meeting program of CISV Yottametre, a unit for length or distance YM (selective medium), a combination of yeast and mold, a selective medium Yarmouth Mariners, a... Typical divisions Ascomycota (sac fungi) Saccharomycotina (true yeasts) Taphrinomycotina Schizosaccharomycetes (fission yeasts) Basidiomycota (club fungi) Urediniomycetes Sporidiales Yeasts are a growth form of eukaryotic microorganisms classified in the kingdom Fungi, with approximately 1,500 species described. ... It has been suggested that Toxic mold be merged into this article or section. ... The correct title of this article is . ... An agar plate is a sterile Petri dish that contains agar plus nutrients, and is used to culture bacteria or fungi. ... The group A streptococcus bacterium (Streptococcus pyogenes, or GAS) is a form of Streptococcus bacteria responsible for most cases of streptococcal illness. ... Streptococcus is a genus of spherical shaped Gram-positive bacteria, belonging to the phylum Firmicutes[1] and the lactic acid bacteria group. ... MacConkeys Agar is a culture medium designed to grow up Gram-negative bacteria and stain them for lactose fermentation. ... Bacteria that are Gram-negative are not stained dark blue or violet by Gram staining, in contrast to Gram-positive bacteria. ... Buffered charcoal yeast extract (BCYE) agar is a selective growth medium used to culture or grow certain bacteria, particularly the Gram-negative species Legionella pneumophila and Haemophilus influenzae. ... Binomial name Legionella pneumophila Brenner DJ, Steigerwalt AG, McDade JE 1979 Legionella pneumophila is a thin, pleomorphic, flagellated Gram-negative bacterium of the genus Legionella. ...

Differential media

Differential media or indicator media distinguish one microorganism type from another growing on the same media.^[4] This type of media uses the biochemical characteristics of a microorganism growing in the presence of specific nutrients or indicators (such as neutral red, phenol red, eosin y, or methylene blue) added to the medium to visibly indicate the defining characteristics of a microorganism. This type of media is used for the detection of microorganisms and by molecular biologists to detect recombinant strains of bacteria. Neutral Red (or toluylene red, Basic Red 5, or C.I. 50040) is an eurhodin dye used for staining in histology. ... Phenol red (also known as phenolsulfonphthalein or PSP) is a pH indicator that is frequently used in cell biology laboratories. ... Eosin is an orange-pink dye derived from coal tar. ... Methylene blue is a heterocyclic aromatic chemical compound with molecular formula: C16H18ClN3S. It has many uses in a range of different fields, such as biology or chemistry. ... Recombinant proteins are proteins that are produced by different genetically modified organisms following insertion of the relevant DNA into their genome. ...

Examples of differential media include:

• Eosin methylene blue (EMB), which is differential for lactose and sucrose fermentation
• MacConkey (MCK), which is differential for lactose fermentation
• Mannitol Salt Agar (MSA), which is differential for mannitol fermentation
• X-gal plates, which are differential for lac operon mutants

Eosin mythylene blue (EMB) is a selective stain for Gram-negative bacteria. ... MacConkeys Agar is a culture medium designed to grow up Gram-negative bacteria and stain them for lactose fermentation. ... The lac operon is an operon required for the transport and metabolism of lactose in Escherichia coli and some other enteric bacteria. ...

Transport media

These are used for the temporary storage of specimens being transported to the laboratory for cultivation. Such media ideally maintain the viability of all organisms in the specimen without altering their concentration. Transport media typically contains only buffers and salt. The lack of carbon, nitrogen, and organic growth factors prevents microbial multiplication. Transport media used in the isolation of anaerobes must be free of molecular oxygen.

Enriched media

Enriched media contain the nutrients required to support the growth of a wide variety of organisms, including some of the more fastidious ones. They are commonly used to harvest as many different types of microbes as are present in the specimen. Blood agar is an enriched medium in which nutritionally rich whole blood supplements the basic nutrients. Chocolate agar is enriched with heat-treated blood (40-45°C), which turns brown and gives the medium the color for which it is named. An agar plate is a sterile Petri dish that contains agar plus nutrients, and is used to culture bacteria or fungi. ... Wikibooks Transwiki has more about this subject: Agar plate An agar plate streaked with microorganisms isolated from a deep-water sponge. ...

See also

• Cell biology

This article or section includes a list of works cited or a list of external links, but its sources remain unclear because it lacks in-text citations. ...

References

External links

• The Nutrient Requirements of Cells
• Growth of Animal Cells in Culture