NationMaster - Encyclopedia: Listeria

Listeria is a bacterial genus containing six species. Named in honour of Joseph Lister, Listeria species are Gram positive bacilli and are typified by L. monocytogenes, the causative agent of Listeriosis. 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. ... For other uses of the word, please see Genus (disambiguation). ... Joseph Lister, 1st Baron Lister (April 5, 1827-February 10, 1912) was a famous British surgeon who promoted the idea of sterile surgery while working at the Glasgow Infirmary. ... Gram-positive Bacillus anthracis bacteria (purple rods) in cerebrospinal fluid sample. ... Orders Bacillales Lactobacillales The term bacilli (singular bacillus) is used to refer to any rod-shaped bacteria. ... Binomial name Listeria monocytogenes Murray , 1926 Listeria monocytogenes is a Gram-positive bacterium, in the division Firmicutes, named for Joseph Lister. ...

Listeria ivanovii is a pathogen of ruminants, and can infect mice in the laboratory, although it is only rarely the cause of human disease. This article does not adequately cite its references or sources. ... Feral mouse A mouse (plural mice) is a rodent that belongs to one of numerous species of small mammals. ... The term disease refers to an abnormal condition of an organism that impairs function. ...

Listeria monocytogenes

Listeria monocytogenes is a bacterium commonly found in soil, stream water, sewage, plants, and food.^[1] Each bacterium is Gram-positive and rod-shaped. Listeria are known to be the bacteria responsible for listeriosis, a rare but lethal food-borne infection that has a devastating mortality rate of 25%^[2](Salmonella, in comparison, has a less than 1% mortality rate^[3]). They are incredibly hardy and able to grow in temperatures ranging from 4°C, the temperature of a refrigerator, to 37°C, the body's internal temperature^[1]. Furthermore, listerosis's deadliness can be partially attributed to the infection's ability to spread to the nervous system and cause meningitis.^[1] Finally, Listeria has a particularly high occurrence rate in newborns because of its ability to infect the fetus by penetrating the endothelial layer of the placenta.^[2] Species Salmonella bongori Salmonella enterica Salmonella arizonae Salmonella enteritidis Salmonella typhi Salmonella typhimurium Salmonella is a genus of rod-shaped Gram-negative enterobacteria that causes typhoid fever, paratyphoid fever, and foodborne illness. ... Meningitis is the inflammation of the protective membranes covering the central nervous system, known collectively as the meninges. ... The placenta is an ephemeral (temporary) organ present in female placental vertebrates during gestation (pregnancy), but a placenta has evolved independently also in other animals as well, for instance scorpions and velvet worms. ...

Pathogenesis

Listeria uses the cellular machinery to move around inside the host cell: it induces directed polymerization of actin by the ActA transmembrane protein, thus pushing the bacterial cell around. G-Actin (PDB code: 1j6z). ... A transmembrane protein is a protein that spans the entire biological membrane. ...

Listeria monocytogenes for example, encodes virulence genes which are thermoregulated. The expression of virulence factor is optimal at 37 degrees Celsius and is controlled by a transcriptional activator, PrfA, whose expression is thermoregulated. At low temperatures, the PrfA transcript is not translated due to structural elements near the ribosome binding site. As the bacteria infects the host, the temperature of the host melts the structure and allows translation initiation for the virulent genes.

Mechanism of Infection

The majority of Listeria bacteria are targeted by the immune system before they are able to cause infection. Those that escape the immune system's initial response, however, spread infection though intracellular mechanisms and are therefore guarded against circulating immune factors (AMI).^[2] A scanning electron microscope image of a single neutrophil (yellow), engulfing anthrax bacteria (orange). ... An infection is the detrimental colonization of a host organism by a foreign species. ...

To invade, Listeria induces macrophage phagocytic uptake by displaying D-galactose receptors that are then bound by the macrophage's polysaccharide receptors (Notably, in most bacterial infections it is the host cell, not the bacteria, that displays the polysaccharide). ^[3] Once phagocytosised, the bacteria is encapsulated by the host cell's acidic phagolysosome organelle. ^[1] Listeria, however, escapes the phagolysosome by lysing the vacuole's entire membrane with secreted hemolysin, ^[4] now characterized to be the exotoxin listeriolysin-O .^[1] The bacteria replicate inside the host cell's cytoplasm. ^[2] Phagocytosis is a form of endocytosis wherein large particles are enveloped by the cell membrane of a (usually larger) cell and internalized to form a phagosome, or food vacuole. ... A macrophage of a mouse stretching its arms to engulf two particles, possibly pathogens Macrophages (Greek: big eaters, makros = long, phagein = eat) are white blood cells, more specifically phagocytes, acting in the nonspecific defense as well as the specific defense system of vertebrate animals. ... Polysaccharides (sometimes called glycans) are relatively complex carbohydrates. ...

The Listeria must then navigate to the cells peripheral to spread the infection to other cells. Outside of the body, Listeria has flagellar driven motility. At 37°C however, flagella ceases to develop and the bacteria instead usurps the host cells cytoskeleton to move. ^[2] The Listeria, inventively, polymerizes an actin tail or "comet" ^[4], using host-produced actin filaments ^[5] with the promotion of virulence factor ActA^[2]. The comet forms in a polar manner ^[6] and aids the bacteria's migration to the host cells outer membrane. Gelsolin, an actin filament severing protein, localizes at the tail of the Listeria and accelerates the bacteria's motility.^[6] Once at the cell surface, the actin propelled Listeria pushes against the cell's membrane to form protrusions called filopods^[1] or "rockets". The protrusions are guided by the cell's leading edge ^[7]to contact adjacent cells which subsequently engulf the Listeria rocket and the process is repeated.^[2] Once first phagocytosised, the Listeria is never again extracellular: it is an intracytoplasmic parasite ^[4] like Shigella flexneri and rickettsia.^[2] A flagellum (plural, flagella) is a whip-like organelle that many unicellular organisms, and some multicellular ones, use to move about. ... The eukaryotic cytoskeleton. ... Shigella Flexneri can cause diarrhea in humans. ... Species Rickettsia felis Rickettsia prowazekii Rickettsia rickettsii Rickettsia typhi Rickettsia conorii Rickettsia africae etc. ...

Epidemiology

The Center for Science in the Public Interest has published a list of foods that have sometimes caused outbreaks of Listeria: hot dogs, deli meats, raw milk, cheeses (particularly soft-ripened cheeses like feta, Brie, Camembert, blue-veined, or Mexican-style “queso blanco”), raw and cooked poultry, raw meats, ice cream, raw vegetables, raw and smoked fish.^[8] The references in this article would be clearer with a different and/or consistent style of citation, footnoting or external linking. ...

Prevention

The prevention of Listeria as a food illness involves effective sanitizing of food contact surfaces. Alcohol has proven to be an effective topical sanitizer against Listeria. Quaternary ammonium can be used in conjunction with alcohol as a food contact safe sanitizer with increased duration of the sanitizing action. Nonflammable Alcohol Vapour in carbon dioxide NAV-CO2 systems or sodium hypochlorite are frequently used to sanitize surfaces to prevent Listeria. Functional group of an alcohol molecule. ... Quaternary ammonium cation. ... Non-flammable Alcohol Vapor in Carbon Dioxide (NAV-CO2) systems were developed in Japan in the 1990s to sanitize hospitals and ambulances. ...

Modern Relevance/Future Research

Listeriosis is an opportunistic pathogen: it is most prevalent in the elderly, pregnant mothers, and AIDS patients. With improved healthcare leading to a growing elderly population and extended life expectancies for AIDS patients, physicians are more likely to encounter this otherwise rare infection (only 0.7 per 100,000 healthy people are infected with virulent Listeria each year).^[1]Better understanding the cell biology of Listeria infections, including relevant virulence factors, may help us better treat Listeriosis and other intracytoplasmic parasites.

Finally, researchers are now investigating the use of Listeria as a cancer vaccine, taking advantage of its "ability induce potent innate and adaptive immunity."^[5]

Treatment

Antibiotics effective against Listeria species include Ampicillin, vancomycin, ciprofloxacin, linezolid, azithromycin, and cotrimoxazole. Ampicillin is a beta-lactam antibiotic that has been used extensively to treat bacterial infections since 1961. ... Crystal structure of a short peptide L-Lys-D-Ala-D-Ala (bacterial cell wall precursor, in green) bound to vancomycin (blue) through hydrogen bonds. ... Ciprofloxacin is the generic international name for the synthetic antibiotic manufactured and sold by Bayer Pharmaceutical under the brand names Cipro and Ciproxin (and other brand names in other markets, e. ... Linezolid is a synthetic systemic antibiotic drug. ... Azithromycin is an azalide, a subclass of macrolide antibiotics. ... Co-trimoxazole (abbreviated SXT, TMP-SMX, or TMP-sulfa) is an antibiotic combination of trimethoprim and sulfamethoxazole, in the ratio of 1 to 5, used in the treatment of a variety of bacterial infections. ...

Future treatment options

Intralytix has created a virus spray with bacteriophages to be applied to food for the prevention of Listeriosis by killing six strains of L. monocytogenes bacterium.^[9] Intralytix has created a spray with bacteriophages to be applied to food for the prevention of Listeriosis by killing strains of food-borne pathogenic L. monocytogenes bacterium. ... Binomial name Listeria monocytogenes Murray , 1926 Listeria monocytogenes is a Gram-positive bacterium, in the division Firmicutes, named for Joseph Lister. ...

Genomics

The United States Department of Energy (DOE) is a Cabinet-level department of the United States government responsible for energy policy and nuclear safety. ... The Integrated Microbial Genomes (IMG) is a genome browsing and annotation system developed by the DOE-Joint Genome Institute. ...

See also

References

^ ^a ^b ^c ^d ^e ^f ^g Southwick, F.S.; D.L Purich. More About Listeria. University of Florida Medical School. DOI:.. Retrieved on 7 March 2007.
^ ^a ^b ^c ^d ^e ^f ^g ^h Todar's Online Textbook of Bacteriology. Listeria monocytogenes and Listeriosis. Kenneth Todar University of Wisconsin-Madison Department of Biology (2003). DOI:.. Retrieved on 2007-03-07.
^ ^a ^b Statistics about Salmonella food poisoning. WrongDiagnosis.com (27 February 2007). DOI:.. Retrieved on 2007-03-07.
^ ^a ^b ^c Tinley, L.G. et al (1989). Actin Filaments and the Growth, Movement, and Spread of the Intracellular Bacterial Parasite, Listeria monocytogenes. The Journal of Cell Biology 109: 1597-1608.
^ ^a ^b Listeria. MicrobeWiki.Kenyon.edu (16 August 2006). DOI:.. Retrieved on 2007-03-07.
^ ^a ^b Laine, R.O. et al (1998). Gelsolin, a Protein That Caps the Barbed Ends and Severs Actin Filaments, Enhances the Actin-Based Motility of Listeria monocytogenes in Host Cells. Infection and Immunity 66(8): 3775-3782.
^ Galbraith, C.G. et al (2007). Polymerizing Actin Fibers Position Integrins Primed to Probe for Adhesion Sites. Science 315: 992-995.
^ Center for Science in the Public Interest - Nutrition Action Healthletter - Food Safety Guide - Meet the Bugs
^ Associated Press - Viruses Approved for Treating Food

A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... March 7 is the 66th day of the year (67th in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... March 7 is the 66th day of the year (67th in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... March 7 is the 66th day of the year (67th in leap years) in the Gregorian calendar. ... The references in this article would be clearer with a different and/or consistent style of citation, footnoting or external linking. ... The Associated Press, or AP, is an American news agency, the worlds largest such organization. ...

Contents

Listeria monocytogenes