Legionella pneumophila: Difference between revisions
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'''''Propionibacterium acnes''''' | '''''Propionibacterium acnes''''' | ||
==Taxonomic Classification== | ==Taxonomic Classification== | ||
'''''Higher Order Taxa:''''' | '''''Higher Order Taxa:''''' | ||
''Bacteria''; '' | ''Bacteria''; ''Proteobacteria''; ''Gammaproteobacteria''; ''Legionellales''; ''Legionellacaea''; ''Legionella''; ''Legionella pneumophila'' | ||
==Description and significance== | |||
The Legionellaceae are fastidious gram-negative bacteria that reside in aquatic environments all over the globe. In their natural environment, the Legionellaceae are intracellular parasites of free-living protozoa. These organisms may also inhabit manmade water distribution systems. The family Legionellaceae consists of a single genus, Legionella. More specifically, this genus includes the species L. pneumophila, which are nonencapsulated, aerobic bacillus. In addition to L. pneumophila, there are 41 other species in the genus and together these species divide into 64 serogroups. Within the species L. pneumophila, human infection is caused primarily (but not exclusively) by a limited number of serogroups—serogroups 1, 4, and 6. L. pneumophila is the most frequent cause of human legionellosis, better known as Legionnaire’s disease in the Legionellaceae family. It is also a relatively common cause of community-acquired and nosocomial pneumonia in adults. (1) And L. pneumophila serogroup 1 alone is responsible for 70-90% of cases. (2) | |||
The Legionellaceae were not documented until 1976, when a detrimental outbreak of pneumonia occurred in Philadelphia at an American Legion Convention. (Fraser et al., 1977; Tsai et al., 1979). Thirty four of the 221 people who became ill after exposure died within the first few weeks after the convention. The culprit, L. pneumophila, was isolated first by inoculation of postmortem lung tissue into guinea pigs and then by subculture into a rich artificial medium (McDade et al., 1977). Then by indirect immunofluorescent antibody assay, it was found that over 90% of those that fell ill had at least four times the concentration of antibody in the blood (fourfold rise in titer) against this organism. The same method was used to screen previously saved sera from earlier outbreaks of unexplained respiratory disease and they discovered that a number of them were associated with seroconversion to L. pneumophila, including a “rickettsia-like” organism, isolated by guinea pig inoculation from the blood of a feverish patient in 1947, which today is recorded as the earliest known isolate of L. pneumophila. (1) | |||
==Genomic Structure== | ==Genomic Structure== | ||
==Cell Structure and Metabolism== | ==Cell Structure and Metabolism== | ||
Revision as of 07:51, 5 June 2007
Propionibacterium acnes
Taxonomic Classification
Higher Order Taxa:
Bacteria; Proteobacteria; Gammaproteobacteria; Legionellales; Legionellacaea; Legionella; Legionella pneumophila
Description and significance
The Legionellaceae are fastidious gram-negative bacteria that reside in aquatic environments all over the globe. In their natural environment, the Legionellaceae are intracellular parasites of free-living protozoa. These organisms may also inhabit manmade water distribution systems. The family Legionellaceae consists of a single genus, Legionella. More specifically, this genus includes the species L. pneumophila, which are nonencapsulated, aerobic bacillus. In addition to L. pneumophila, there are 41 other species in the genus and together these species divide into 64 serogroups. Within the species L. pneumophila, human infection is caused primarily (but not exclusively) by a limited number of serogroups—serogroups 1, 4, and 6. L. pneumophila is the most frequent cause of human legionellosis, better known as Legionnaire’s disease in the Legionellaceae family. It is also a relatively common cause of community-acquired and nosocomial pneumonia in adults. (1) And L. pneumophila serogroup 1 alone is responsible for 70-90% of cases. (2) The Legionellaceae were not documented until 1976, when a detrimental outbreak of pneumonia occurred in Philadelphia at an American Legion Convention. (Fraser et al., 1977; Tsai et al., 1979). Thirty four of the 221 people who became ill after exposure died within the first few weeks after the convention. The culprit, L. pneumophila, was isolated first by inoculation of postmortem lung tissue into guinea pigs and then by subculture into a rich artificial medium (McDade et al., 1977). Then by indirect immunofluorescent antibody assay, it was found that over 90% of those that fell ill had at least four times the concentration of antibody in the blood (fourfold rise in titer) against this organism. The same method was used to screen previously saved sera from earlier outbreaks of unexplained respiratory disease and they discovered that a number of them were associated with seroconversion to L. pneumophila, including a “rickettsia-like” organism, isolated by guinea pig inoculation from the blood of a feverish patient in 1947, which today is recorded as the earliest known isolate of L. pneumophila. (1)
Genomic Structure
Cell Structure and Metabolism
Ecology
Pathology
Applications to Biotechnology
Current Research
References
Allison, Clive et al. Dissimilatory Nitrate Reduction by Propionibacterium acnes. Applied and Environmental Microbiology. 1989. Vol. 55 (11): 2899-2903.
Brüggemann, Holger et al. The Complete Genome Sequence of Propionibacterium Acnes, a Commensal of Human Skin. Science. 2005. 305: p. 671-672.
Farrar, Mark D. et al. Genome Sequence and Analysis of a Propionibacterium acnes Bacteriophage, Journal of Bacteriology.2007. Vol. 189 (11) p. 4161–4167.
Higaki, Shuichi et al. Propionibacterium acnes Biotypes and Susceptibility to Minocycline and Keigai-rengyo-to. International Journal of Dermatology. 2004. 43: p. 103–107.
Ingham, Eileen The Immunology of Propionibacterium acnes and Acne. Current Opinion in Infectious Diseases. 1999. Vol. 12(3): p. 191-197.
Liavonchanka, Alena et al. Structure and Mechanism of the Propionibacterium acnes Polyunsaturated Fatty Acid Isomerase. PNAS. 2006. Vol. 103 (8): p. 2581.
Moore, W.E.C. et al. Validity of Propionibacterium acnes (Gilchrist) Douglas and Gunter Comb. Nov. Journal of Bacteriology. 1962. p. 870-874.
Oprica, Cristina et al. Clinical and Microbiological Comparisons of Isotretinoin vs. Tetracycline in Acne Vulgaris. Acta Derm Venereol. 2007. Vol. 87: p. 246–254.
Rosenberg, E. William Bacteriology of Acne. Annual Reviews. 1969. Vol. 20: p. 201-206.
This page was created by Christopher B. Smith under the supervision of Professors Rachel Larson and Kit Pogliano at the University of California, San Diego.
