Enterococcus faecalis: Difference between revisions
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==Description and significance== | ==Description and significance== | ||
Enterococcus are gram-positive cocci that can survive harsh conditions in nature and thus are ubiquitous, being found in soil, water, and plants. They colonize the gastrointestinal and gential tracts of humans. While there are over 15 species in the genus, 80-90% of clinical isolates are E. faecalis. | |||
In the last decade, vancomycin-resistnat enerococci and ther nosocomial spread have become a major challenge. In general, enttercoccal isolates with reduced susceptibility to vancomycin can be categorized as vanA, vanB, and vanC. vanA and vanB pose the greatest threat because they are the most resistant and the resistance genes are carries on a plasmid and thus are readily transeferable. vanA isolates, predominanatly E. faecalis strains, are typically associated with vancomycin MICs of >= 256 μg/ml and are also resistant to teicoplanin. Occasional enterococcal strains that are vancomycin dependent have been reported. These starins are less common that vancomycin-resistant strains. | |||
Enterocci typically form short chains or are arranged in pairs; however, under certain growth conditions they elongate and appear coocobacillary. In general, enterococci are alpha-hemlytic. Some possess the group D Lancefield antigen and cen be detected using monoclonal antibody-based agglutination tests. Enterococci are typically catalase negative, grow over a wide temperature range from 10 to 42°C, and are anaerobic. They are able to grow in 6.5% NaCl, hydrolyze esulin in the presence of 40% bile salts, and are pyrrolidonyl arylamidase and leucine arylamidase positive. | |||
==Genome structure== | ==Genome structure== | ||
Revision as of 22:09, 29 April 2007
Classification
Higher order taxa
Bacteria; Firmicutes; Bacilli; Lactobacillales; Enterococcaceae; Enterococcus
Genus
Enterococcus faecalis
Description and significance
Enterococcus are gram-positive cocci that can survive harsh conditions in nature and thus are ubiquitous, being found in soil, water, and plants. They colonize the gastrointestinal and gential tracts of humans. While there are over 15 species in the genus, 80-90% of clinical isolates are E. faecalis.
In the last decade, vancomycin-resistnat enerococci and ther nosocomial spread have become a major challenge. In general, enttercoccal isolates with reduced susceptibility to vancomycin can be categorized as vanA, vanB, and vanC. vanA and vanB pose the greatest threat because they are the most resistant and the resistance genes are carries on a plasmid and thus are readily transeferable. vanA isolates, predominanatly E. faecalis strains, are typically associated with vancomycin MICs of >= 256 μg/ml and are also resistant to teicoplanin. Occasional enterococcal strains that are vancomycin dependent have been reported. These starins are less common that vancomycin-resistant strains.
Enterocci typically form short chains or are arranged in pairs; however, under certain growth conditions they elongate and appear coocobacillary. In general, enterococci are alpha-hemlytic. Some possess the group D Lancefield antigen and cen be detected using monoclonal antibody-based agglutination tests. Enterococci are typically catalase negative, grow over a wide temperature range from 10 to 42°C, and are anaerobic. They are able to grow in 6.5% NaCl, hydrolyze esulin in the presence of 40% bile salts, and are pyrrolidonyl arylamidase and leucine arylamidase positive.
Genome structure
Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence? Does it have any plasmids? Are they important to the organism's lifestyle?
Cell structure and metabolism
Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.
Ecology
Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.
Pathology
How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.
Application to Biotechnology
Does this organism produce any useful compounds or enzymes? What are they and how are they used?
Current Research
Enter summaries of the most recent research here--at least three required
References
example:
De la Maza, Luis M., Marie T. Pezzlo, and Janet T. Shigei. Color Atlas of Medical Bacteriology. Washington, DC: American Society for Microbiology, 2004.
Edited by Richard A. Martinez of UC San Diego, student of Rachel Larsen.
