Community hub
Recent from talks
Knowledge base stats:
Talk channels stats:
Members stats:
Serratia marcescens
Serratia marcescens (/səˈreɪʃiə mɑːrˈsɛsɪnz/)[failed verification] is a species of rod-shaped, Gram-negative bacteria in the family Yersiniaceae. It is a facultative anaerobe and an opportunistic pathogen in humans. It was discovered in 1819 by Bartolomeo Bizio in Padua, Italy. S. marcescens is commonly involved in hospital-acquired infections (HAIs), also called nosocomial infections, particularly catheter-associated bacteremia, urinary tract infections, and wound infections, and is responsible for 1.4% of HAI cases in the United States. It is commonly found in the respiratory and urinary tracts of hospitalized adults and in the gastrointestinal systems of children.
Due to its abundant presence in the environment, and its preference for damp conditions, S. marcescens is commonly found growing in bathrooms (especially on tile grout, shower corners, toilet water lines, and basins), where it manifests as a pink, pink-orange, or orange discoloration and slimy film feeding off phosphorus-containing materials or fatty substances such as soap and shampoo residue.
Once established, complete eradication of the organism is often difficult, but can be accomplished by application of a bleach-based disinfectant. Rinsing and drying surfaces after use can also prevent the establishment of the bacterium by removing its food source and making the environment less hospitable.
S. marcescens may also be found in environments such as dirt and the subgingival biofilm of teeth. Due to this, and because S. marcescens produces a reddish-orange tripyrrole dye called prodigiosin, it may cause tooth discoloration. The biochemical pathway for the production of prodigiosin by S. marcescens has been characterized by analyzing what intermediates become accumulated in specific mutants.
S. marcescens is a motile organism and can grow in temperatures ranging 5–40 °C (41–104 °F) and in pH levels ranging from 5 to 9. It is differentiated from other Gram-negative bacteria by its ability to perform casein hydrolysis, which allows it to produce extracellular metalloproteinases which are believed to function in cell-to-extracellular matrix interactions. Since this bacterium is a facultative anaerobe, meaning that it can grow in either the presence of oxygen (aerobic growth) or in the absence of oxygen (anaerobic growth), it is capable of nitrate reduction under anoxic conditions. Therefore, nitrate tests are positive since nitrate is generally used as the final electron acceptor rather than oxygen. S. marcescens also exhibits tyrosine hydrolysis and citrate degradation. Citrate is used by S. marcescens to produce pyruvic acid, thus it can rely on citrate as a carbon source and test positive for citrate utilization. In identifying the organism, one may also perform a methyl red test, which determines if a microorganism performs mixed-acid fermentation. S. marcescens results in a negative test. Another determination of S. marcescens is its capability to produce lactic acid by oxidative and fermentative metabolism. Therefore, S. marcescens is lactic acid O/F+.
In humans, S. marcescens can cause an opportunistic infection in several sites, including the urinary tract, respiratory tract, wounds, breasts, and the eye, where it may cause conjunctivitis, keratitis, endophthalmitis, and tear duct infections. It is also a rare cause of endocarditis and osteomyelitis (particularly in people who use intravenous drugs recreationally), pneumonia, and meningitis. Most S. marcescens strains are resistant to several antibiotics because of the presence of R-factors, which are a type of plasmid that carry one or more genes that encode resistance; all are considered intrinsically resistant to ampicillin, macrolides, and first-generation cephalosporins (such as cephalexin).
In elkhorn coral, S. marcescens is the cause of the disease known as white pox disease. In silkworms, it can also cause a lethal disease, especially in association with other pathogens.
In research laboratories employing Drosophila fruit flies, infection of them with S. marcescens is common.[citation needed] It manifests as a pink discoloration or plaque in or on larvae, pupae, or the usually starch and sugar-based food (especially when improperly prepared).
Hub AI
Serratia marcescens AI simulator
(@Serratia marcescens_simulator)
Serratia marcescens
Serratia marcescens (/səˈreɪʃiə mɑːrˈsɛsɪnz/)[failed verification] is a species of rod-shaped, Gram-negative bacteria in the family Yersiniaceae. It is a facultative anaerobe and an opportunistic pathogen in humans. It was discovered in 1819 by Bartolomeo Bizio in Padua, Italy. S. marcescens is commonly involved in hospital-acquired infections (HAIs), also called nosocomial infections, particularly catheter-associated bacteremia, urinary tract infections, and wound infections, and is responsible for 1.4% of HAI cases in the United States. It is commonly found in the respiratory and urinary tracts of hospitalized adults and in the gastrointestinal systems of children.
Due to its abundant presence in the environment, and its preference for damp conditions, S. marcescens is commonly found growing in bathrooms (especially on tile grout, shower corners, toilet water lines, and basins), where it manifests as a pink, pink-orange, or orange discoloration and slimy film feeding off phosphorus-containing materials or fatty substances such as soap and shampoo residue.
Once established, complete eradication of the organism is often difficult, but can be accomplished by application of a bleach-based disinfectant. Rinsing and drying surfaces after use can also prevent the establishment of the bacterium by removing its food source and making the environment less hospitable.
S. marcescens may also be found in environments such as dirt and the subgingival biofilm of teeth. Due to this, and because S. marcescens produces a reddish-orange tripyrrole dye called prodigiosin, it may cause tooth discoloration. The biochemical pathway for the production of prodigiosin by S. marcescens has been characterized by analyzing what intermediates become accumulated in specific mutants.
S. marcescens is a motile organism and can grow in temperatures ranging 5–40 °C (41–104 °F) and in pH levels ranging from 5 to 9. It is differentiated from other Gram-negative bacteria by its ability to perform casein hydrolysis, which allows it to produce extracellular metalloproteinases which are believed to function in cell-to-extracellular matrix interactions. Since this bacterium is a facultative anaerobe, meaning that it can grow in either the presence of oxygen (aerobic growth) or in the absence of oxygen (anaerobic growth), it is capable of nitrate reduction under anoxic conditions. Therefore, nitrate tests are positive since nitrate is generally used as the final electron acceptor rather than oxygen. S. marcescens also exhibits tyrosine hydrolysis and citrate degradation. Citrate is used by S. marcescens to produce pyruvic acid, thus it can rely on citrate as a carbon source and test positive for citrate utilization. In identifying the organism, one may also perform a methyl red test, which determines if a microorganism performs mixed-acid fermentation. S. marcescens results in a negative test. Another determination of S. marcescens is its capability to produce lactic acid by oxidative and fermentative metabolism. Therefore, S. marcescens is lactic acid O/F+.
In humans, S. marcescens can cause an opportunistic infection in several sites, including the urinary tract, respiratory tract, wounds, breasts, and the eye, where it may cause conjunctivitis, keratitis, endophthalmitis, and tear duct infections. It is also a rare cause of endocarditis and osteomyelitis (particularly in people who use intravenous drugs recreationally), pneumonia, and meningitis. Most S. marcescens strains are resistant to several antibiotics because of the presence of R-factors, which are a type of plasmid that carry one or more genes that encode resistance; all are considered intrinsically resistant to ampicillin, macrolides, and first-generation cephalosporins (such as cephalexin).
In elkhorn coral, S. marcescens is the cause of the disease known as white pox disease. In silkworms, it can also cause a lethal disease, especially in association with other pathogens.
In research laboratories employing Drosophila fruit flies, infection of them with S. marcescens is common.[citation needed] It manifests as a pink discoloration or plaque in or on larvae, pupae, or the usually starch and sugar-based food (especially when improperly prepared).