Pseudomonas aeruginosa

Pseudomonas aeruginosa
Pseudomonas aeruginosa
Systematics
Domain : Bacteria (bacteria) Class : Gammaproteobacteria Order : Pseudomonadales Family : Pseudomonadaceae Genre : Pseudomonas Type : Pseudomonas aeruginosa
Scientific name
Pseudomonas aeruginosa
Migula 1900

Pseudomonas aeruginosa (from latin aerugo , verdigris ') is a gram-negative , oxidasepositives rod-shaped bacterium of the genus Pseudomonas . It wasdiscoveredby Walter Migula in 1900. The name refers to the blue-green color of the pus in purulent infectious diseases.

P. aeruginosa is an important hospital germ that is resistant to several antibiotics.

Occurrence

The bacterium is a widespread soil and water germ ( wet germ ) that occurs in moist environments (in addition to moist soils and surface water, also in tap water, sinks, showers, swimming pools, toilets, dishwashers, dialysis machines, medicines and disinfectants). In terms of hygiene , it is therefore an important hospital germ ( nosocomial germ). But it also plays a significant role as a food spoiler, as demonstrated by isolates from plants, fruits, foods and the intestinal tract of humans and animals. It can survive and grow even in distilled water or some disinfectants when the smallest traces of organic matter are present. The bacteria are also involved in what is known as diesel plague . In process engineering equipment , Pseudomonas aeruginosa can lead, among other things, to clogging of pipelines and material damage due to the formation of biofilms and slime.

Appearance

The rod can be 2–4 µm in size and has tufted lophotric flagella . Adhesive fimbria enable the bacterium to attach itself to surfaces. An exopolysaccharide (alginate) is deposited on the outer cell membrane like a capsule. It protects against phagocytes and antibodies and counteracts transport from the respiratory tract.

metabolism

P. aeruginosa with yellow-green pyocyanin pigment on cetrimide agar

P. aeruginosa with fluorescent pigment under UV light on cetrimide agar

The nonfermenter P. aeruginosa is able to ferment under anaerobic conditions. Pyruvate or arginine are fermented. As an important denitrifier , it is also able to use these as terminal electron acceptors in anaerobic respiration under anaerobic conditions and with access to nitrogen oxides. The ability to denitrify and the ability to form biofilms are important virulence factors for P. aeruginosa (see cystic fibrosis ). In various nutrient media (e.g. cetrimide agar ) it releases dyes such as pyocyanin , pyoverdin , pyorubin and pyomelanin . It is usually “metallic-green” shiny on agar . It is characterized by a sweetish smell described as "linden blossom" or "grape-like" ("gummy bear smell"), which is due to the production of 2-aminoacetophenone (2-AA). Because of its volatility, among other things, 2-AA is a potential biomarker that is selective for P. aeruginosa in connection with an infection in cystic fibrosis patients. It also appears to attract flies and help colonize their intestines without increasing their mortality, thereby facilitating the spread of P. aeruginosa .

Recent research shows that P. aeruginosa can even metabolize sodium lauryl sulfate (SDS) with the help of its own digestive enzyme SdsA . This enables the bacterium to survive where other bacteria are killed due to the high SDS concentration, for example in shampoos.

P. aeruginosa produces so-called rhamnolipids from renewable raw materials under limited growth conditions (e.g. nitrogen , phosphate or iron limitation ) on oils (e.g. sunflower oil ) . Some of these biosurfactants are already being manufactured on a production scale and used in detergents or cosmetics. The cells presumably release the rhamnolipids into the medium surrounding them in order to emulsify the oil and to split the oil into fatty acids and glyceride by means of lipases at the water / oil interfaces . The rhamnolipid synthesis is quorum sensing regulated, so it depends on the cell density in the medium. The Las- and Rhl-regulated quorum sensing are responsible for this.

Genome

In 2000 the complete genome of the strain PAO1 was sequenced for the first time. The genome is 6.3 Mbp in size and contains 5570 genes.

Pathogenicity

Gram stain of P. aeruginosa

The bacterium is a hospital germ that shows multiple resistance to antibiotics due to its metabolism and cell membrane structure. With around 10% of all hospital infections , P. aeruginosa is one of the most common hospital germs in Germany.

The spectrum of diseases caused by these bacteria is extensive. The most common manifestation is pneumonia associated with cystic fibrosis , which is particularly severe in immunocompromised and AIDS patients. Urinary tract infections , enterocolitis , meningitis , otitis externa (“swimmer's ear”) or infections on burns can also be triggered.

The triggers for this are on the one hand the ability of the bacterium to hemolysis and on the other hand pathogenicity factors such as exotoxin A (ADP-ribosyltransferase) and the cytotoxins exoenzyme S and exoenzyme U, which the bacterium produces.

Veterinary medicine

The most common veterinary findings are listed below:

• Inflammation of the external ear canal in the dog
• Suppuration and abscesses of the skin in many species
• Intestinal inflammation
• Udder infections in cows
• Vaginal infections , uterine infections and abortions in cows and mares
• Traumatic pericarditis in cattle
• General infection in poultry
• Ulcerative keratitis and conjunctivitis in horse
• Purulent - necrotizing pneumonia
• Bleeding pneumonia in mink
• Inflammation of the oral mucosa , abscesses and general infections in reptiles

therapy

• β-lactam antibiotics (e.g. piperacillin ) + aminoglycosides (gentamicin, tobramycin)
• Generation IIIb cephalosporins (more effective against Pseudomonas spp. Than generation IIIa) (e.g. ceftazidime , cefepime)
• Gyrase inhibitors such as ciprofloxacin or levofloxacin
• As reserve antibiotics are carbapenems (eg. B. imipenem or meropenem ) and increasingly colistin used.
• Other antibiotics: the monobactam aztreonam

Because of the risk of developing resistance, a combination therapy should always be carried out (if possible based on an antibiogram) rather than monotherapy. Natural resistance exists to ampicillin + sulbactam , amoxicillin + clavulanic acid , most cephalosporins (especially all of the first and second generations), ertapenem , chloramphenicol , trimethoprim , tetracyclines and tigecycline .

literature

• Medical microbiology, infection and epidemic theory by Rolle / Mayr, Enke Verlag, Stuttgart 2007
• Frank Dara: Research topic on Pseudomonas aeruginosa, Biology, Genetics, and Host-Pathogen Interactions. In: Frontiers in Microbiology 2 (2012) (Editorial)
• Markus Wloka: Rheological investigations on native biofilms of Pseudomonas aeruginosa , dissertation, Dortmund 2006

Web links

Commons : Pseudomonas aeruginosa  - collection of images, videos and audio files

• P. aeruginosa in commercial cigarettes
• Delicious lather. (P. aeruginosa also viable in shampoo). On: Wissenschaft.de from May 20, 2006
• The Pseudomonas Genome Project breaks down the complete genome of P. aeruginosa .
• www.systomonas.tu-bs.de - Systems biology database on pseudomonads
• Let the opponent burst. On: Wissenschaft.de from July 20, 2011.

Individual evidence

1. ↑ Hygiene requirements for pools and their monitoring , recommendation of the Federal Environment Agency, Federal Health Gazette 2014 Bl. 258, 260f (PDF) also for the implementation of the Infection Protection Act
2. ↑ VDI 3679 sheet 1: 2014-07 wet separator; Basics, waste gas cleaning of particulate matter (wet separators; Fundamentals, waste gas cleaning of particle collections) . Beuth Verlag, Berlin. P. 48.
3. ↑ Martin Eschbach, Kerstin Schreiber, Katharina Trunk, Jan Buer, Dieter Jahn: Long-Term Anaerobic Survival of the Opportunistic Pathogen Pseudomonas aeruginosa via Pyruvate Fermentation . In: Journal of Bacteriology . tape 186 , no. July 14 , 2004, ISSN  0021-9193 , p. 4596-4604 , doi : 10.1128 / JB.186.14.4596-4604.2004 , PMID 15231792 , PMC 438635 (free full text).
4. ↑ C. Vander Wauven, A Piérard, M-Kley Raymann, D Haas: Pseudomonas aeruginosa mutants affected in anaerobic growth on arginine: evidence for a four-gene cluster encoding the arginine deiminase pathway. In: Journal of Bacteriology . tape 160 , no. 3 , December 1984, ISSN  0021-9193 , pp. 928-934 , PMID 6438064 , PMC 215798 (free full text).
5. ↑ JB Lyczak, CL Cannon, GB Pier: Establishment of Pseudomonas aeruginosa infection: lessons from a versatile opportunist . In: Microbes and Infection . tape 2 , no. July 9 , 2000, ISSN  1286-4579 , pp. 1051-1060 , PMID 10967285 .
6. ↑ Amy J Scott-Thomas, Mona Syhre, Philip K Pattemore, Michael Epton, Richard Laing: 2-Aminoacetophenone as a potential breath biomarker for Pseudomonas aeruginosa in the cystic fibrosis lung . In: BMC Pulmonary Medicine . tape 10 , no. 1 , December 2010, ISSN  1471-2466 , p. 56 , doi : 10.1186 / 1471-2466-10-56 , PMID 21054900 , PMC 2989937 (free full text) - ( biomedcentral.com [accessed January 12, 2020]).
7. ↑ Stefania-Elisavet Kapsetaki, Ilias Tzelepis, Kalodoti Avgousti, Ioannis Livadaras, Nikos Garantonakis: The bacterial metabolite 2-aminoacetophenone promotes association of pathogenic bacteria with flies . In: Nature Communications . tape 5 , no. 1 , December 2014, ISSN  2041-1723 , p. 4401 , doi : 10.1038 / ncomms5401 ( nature.com [accessed January 12, 2020]).
8. ↑ Hagelüken, Gregory et al. (2006): The crystal structure of SdsA1, an alkylsulfatase from Pseudomonas aeruginosa, defines a third class of sulfatases In: PNAS , Vol. 103, pp. 7631–7636 PMID 16684886 doi: 10.1073 / pnas.0510501103
9. ↑ F. Leitermann: Biotechnological production of microbial rhamnolipids . Karlsruhe 2008, University of Karlsruhe (TH)
10. ↑ Stover, CK et al. (2000): Complete genome sequence of Pseudomonas aeruginosa PAO1, an opportunistic pathogen In: Nature Vol. 406 (6799), pp. 947-8, PMID 10984043
11. ↑ Kozlova, EV, LA Anisimova, et al. (1989): [Antibiotic resistance in clinical strains of Pseudomonas aeruginosa isolated from 1979-1984]. In: Antibiot Khimioter 34 (1): 24-8. PMID 2499281
12. ↑ Journal of chemotherapy 3-2008 ( Memento of 15 June 2012 at the Internet Archive )
13. ^ 1st floor: The "renaissance" of the polymyxins. (PDF; 371 kB) In: Medicinal Therapy Volume 29, 2011, pp. 71–80.
14. ^ Marianne Abele-Horn: Antimicrobial Therapy. Decision support for the treatment and prophylaxis of infectious diseases. With the collaboration of Werner Heinz, Hartwig Klinker, Johann Schurz and August Stich, 2nd, revised and expanded edition. Peter Wiehl, Marburg 2009, ISBN 978-3-927219-14-4 , pp. 194 and 266.
15. ^ R. Leclercq et al .: EUCAST expert rules in antimicrobial susceptibility testing . In: Clinical Microbiology and Infection . tape 19 , no. 2 . Wiley-Blackwell, 2013, ISSN  1469-0691 , pp. 141-160 , doi : 10.1111 / j.1469-0691.2011.03703.x , PMID 22117544 ( wiley.com [accessed February 17, 2013]).