Proteus vulgaris: Difference between revisions
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- In conclusion, low-dose of penicillin stopped cell septation in ''P. vulgaris'' P 18 and caused its transformation into filaments without changing the structure of cell envelope. In the penicillin-induced filaments, lysozyme penetrated the cell envelope and dissolved the inner most layer of the cell wall. The action of penicillin caused removal of the barrier to this enzyme. As a result, the five-layered wall is reduced to three-layered structure. This three-layered structure contained the outer membrane and the filament was transformed into spheroplasts.<br /> | - In conclusion, low-dose of penicillin stopped cell septation in ''P. vulgaris'' P 18 and caused its transformation into filaments without changing the structure of cell envelope. In the penicillin-induced filaments, lysozyme penetrated the cell envelope and dissolved the inner most layer of the cell wall. The action of penicillin caused removal of the barrier to this enzyme. As a result, the five-layered wall is reduced to three-layered structure. This three-layered structure contained the outer membrane and the filament was transformed into spheroplasts.<br /> | ||
'''"How long do nosocomial pathogens persist on inanimate surfaces? A systematic review"''' | '''"How long do nosocomial pathogens persist on inanimate surfaces? A systematic review"'''<br /> | ||
-The data on the different nosocomial pathogens on inanimate surface was collected by Axel Kramer,Ingeborg Schwebke,and Günter Kampf. | -The data on the different nosocomial pathogens on inanimate surface was collected by Axel Kramer,Ingeborg Schwebke,and Günter Kampf. <br /> | ||
-The result showed that ''Proteus vulgaris'' stayed 1-2 days. | -The result showed that ''Proteus vulgaris'' stayed 1-2 days.<br /> | ||
- | - | ||
Revision as of 21:54, 31 March 2008
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Classification
Higher order taxa
Domain: Bacteria
Phylum: Proteobacteria
Class: Gamma Proteobacteria
Order: Enterobacteriales
Family: Enterobacteriaceae
Species
Proteus vulgaris
Description and significance
P. vulgaris is rod-shaped gram-negative chemoheterotroph. It inhabits in gastrointestinal tracts of animal, soil, polluted water, raw meat, and dust.
P.vulgaris is considered to be pathogenic bacteria. In human, it can cause urinary tract infections, wound infections, and is a common cause of sinus and respiratory infections.
Proteus can be isolated from a sample of soil. Organism is inoculated in a nutrient agar to form colonies. To test the gram-negative and oxidase-negative characteristics of Enterobacteriaceae, gram stains and the oxidase test are performed. The colonies of interest are then inoculated onto a selective and differential medium-McConkey agar. McConkey agar is suitable for Proteus for two reasons. First reason is that the bile salt constituent allows the growth of Proteus, which is a part of the intestinal flora, while selectively inhibits organisms that are not suitable to grow in interstinal environments. Second reason is that McConkey agar can differentiate the non lactose-fermenting characteristic of Proteus from the lactose-fermenting organisms. Since Proteus is an anaerobic organism, the plate agar can be incubated in an anaerobic jar.[1]
Genome structure
The nucleotide sequencing of Rts1 was completed at Shinshu University School of Medicine, Department of Bacteriology, Japan. Rts1 is a large conjugative plasmid isloated from Proteus vulgaris. The genome is 217,182 bp in length and contains 300 open reading frames(ORFs). The products of 141 ORFs out of 300 ORFs showed significant sequence similarity to known proteins and among these, 99 ORFs were homologous to proteins whose functions are known or predicted. The interesting finding in this study was the presence of tus-like genes that could be involved in replication termination. [2]
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
Proteus species possess an extracytoplasmic outer membrane, a feature shared with other gram-negative bacteria. In addition, the outer membrane contains a lipid bilayer, lipoproteins, polysaccharides, and lipopolysaccharides.
Proteus vulgaris is described as always fermenting glucose and sucrose, with gas production, but never lactose; liquefying gelatin, casein, and blood serum, curdling milk with acid production.
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
P. vulgaris and P. mirabilis are two common species of genus Proteus associated with human infection. Due to presence of peritrichouse flagella, Proteus has extremely high motility. If it were the size of human, it can travel at speed of 100 mph. The most common infections caused by this genus are urinary tract infection(UTI) and wound infection. P. mirabilis is a major agent in UTI. Proteus is abundant in urease production. Urease splits urea into carbon dioxide (CO2) and ammonia (NH3). Ammonia causes the urine to become extremely alkaline (pH >7) and may cause the formation of renal stones. Some of the symptoms of Proteus infection may be UTI, flank pain, hematuria, persistent urine pH >7.
In animals, some strains of Proteus can be harmful while some do not affect the organism. The Proteus isolated from the vomited material from patients with meat-poison caused diarrhea and death when fed to mice. When different cultured Proteus was fed to mice, neither sickness nor immunity were present. When P. vulgaris was injected into the peritoneal cavity of guinea piga, it caused rapid death. However, when the same amount was injected into the subcutis, an extensive necrosisresulted. Intravenous injection in cats caused severe vomiting, bloody diarrhea and death.
Current Research
"Antibacterial and antifungal activities of different parts of Tribulus terrestris L. growing in Iraq"
- Antimicrobial activity of organic and aqueous extracts from fruits, leaves and roots of Tribulus terrestris was examined against 11 species of organisms including Proteus vulgaris.Tribulus terrestris is an Iraqi medicinal plant that is used as urinary anti-infective in folk medicine. Different parts of Turkish and Iranian T. terrestris are already known to have antibacterial activity but the antimicrobial activity of Iraqi T. terrestris has not been studied until this experiment.
- Different extracts from fruits, leaves and roots of Iraqi T. terrestris were tested at concentrations of 0.01~5.00 mg/ml, and evaluated in MIC values. Ethanol extract of T. terrestris fruit was most active against both gram-positive and gram-negative including P. vulgaris with the MIC value of 0.15 mg/ml. The result of aqueous extract from T. terrestris leaves showed that it was active against P. vulgaris with MIC value of 2.50 mg/ml. Extracts from T. terrestris roots showed no activity or very little activity against targeted bacteria.
- In conclusion, all of the extracts from T. terrestris growing in Iraq have ability to inhibit the growth of most of the tested organisms. The gram-positive bacteria were most sensitive to the ethanol extract of T. terrestris fruits, while P. vulgaris was the most resistant among the tested gram-negative bacteria.
"Action of Lysozyme on Penicillin-Induced Filaments of Proteus vulgaris"
- Low-dose of penicillin causes gram-negative bacteria to transform into filaments, but penicillin itself does no harm to cell envelopes and cell wall. The study done by Jacqueline Fleck, Jean-Pierre Martin, and Michèle Mock demonstrates that the hen egg white lysozyme, which does not affect normal cells of P. vulgaris P 18, modifies the envelope of filaments.
- In conclusion, low-dose of penicillin stopped cell septation in P. vulgaris P 18 and caused its transformation into filaments without changing the structure of cell envelope. In the penicillin-induced filaments, lysozyme penetrated the cell envelope and dissolved the inner most layer of the cell wall. The action of penicillin caused removal of the barrier to this enzyme. As a result, the five-layered wall is reduced to three-layered structure. This three-layered structure contained the outer membrane and the filament was transformed into spheroplasts.
"How long do nosocomial pathogens persist on inanimate surfaces? A systematic review"
-The data on the different nosocomial pathogens on inanimate surface was collected by Axel Kramer,Ingeborg Schwebke,and Günter Kampf.
-The result showed that Proteus vulgaris stayed 1-2 days.
-