''Proteus vulgaris'' is a rod-shaped, nitrate-reducing,

indole Indole is an aromatic heterocyclic organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other c ...

-positive and catalase-positive, hydrogen sulfide-producing, Gram-negative bacterium that inhabits the intestinal tracts of humans and animals. It can be found in soil, water, and

fecal Feces ( or faeces), known colloquially and in slang as poo and poop, are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine. Feces contain a relati ...

matter. It is grouped with the Morganellaceae and is an opportunistic pathogen of humans. It is known to cause

wound infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dis ...

s and other species of its genera are known to cause

urinary tract infection A urinary tract infection (UTI) is an infection that affects part of the urinary tract. When it affects the lower urinary tract it is known as a bladder infection (cystitis) and when it affects the upper urinary tract it is known as a kidne ...

s. ''P. vulgaris'' was one of the three species Hauser isolated from putrefied meat and identified (1885). Over the past two decades, the genus ''Proteus'', and in particular ''P. vulgaris'', has undergone a number of major taxonomic revisions. In 1982, ''P. vulgaris'' was separated into three biogroups on the basis of

production. Biogroup one was indole negative and represented a new species, ''P. penneri'', while biogroups two and three remained together as ''P. vulgaris''.

Lab identification

According to laboratory fermentation tests, ''P. vulgaris'' ferments glucose and amygdalin, but does not ferment mannitol or lactose. ''P. vulgaris'' also tests positive for the methyl red (mixed acid fermentation) test and is also an extremely motile organism. When ''P. vulgaris'' is tested using the API 20E identification system it produces positive results for sulfur reduction, urease production, tryptophan deaminase production, indole production, sometimes positive gelatinase activity, and saccharose fermentation, and negative results for the remainder of the tests on the testing strip. It is referenced in the

Analytical Profile Index The analytical profile index or API is a classification of bacteria based on biochemical tests, allowing fast identification. This system is developed for quick identification of clinically relevant bacteria. Because of this, only known bacteri ...

using the nine-digit code: 047602157. The optimal growing conditions of this organism is in a facultative anaerobic environment with an average temperature of about 40 °C. The Becton/Dickinson BBL Enterotube II system for identification of members of the order Enterobacterales inoculated with ''P. vulgaris'' may yield the following results: *Positive for glucose fermentation (with gas production) *Negative for lysine and ornithine *Positive for hydrogen sulfide production and indole production *Negative for lactose, arabinose, adonitol, sorbitol and dulcitol *Positive for the phenylalanine test and the Harnstoff urea test ''P. vulgaris'' can test positive or negative for citrate. All combine for a Biocode ID of 31406, (Biocode ID 31402, 31404, 31407 all resulting in ''P. vulgaris'' with asymptomatic results) for use in the Interpretation Guide/Computer Coding and Identification System. ''P. vulgaris'' can also test urease negative in solid media (such as in Enterotube), but will be urease positive in liquid media. The CCIS code will still identify it with a negative urease test. When inoculated in a gelatin stab test, ''P. vulgaris'' is capable of hydrolysis of gelatin.

''Proteus'' infections

Cause and epidemiology

*Nosocomial infections *''P. mirabilis'' causes 9% of ''Proteus'' infections. *''P. vulgaris'' and ''P. penneri'' are easily isolated from individuals in long-term care facilities and hospitals and from patients with underlying diseases or compromised immune systems. *Patients with recurrent infections, those with structural abnormalities of the urinary tract, those who have had urethral instrumentation, and those whose infections were acquired in the hospital have an increased frequency of infection caused by ''Proteus'' and other organisms (e.g., ''Klebsiella'', ''Enterobacter'', ''Pseudomonas'', enterococci, and staphylococci). *P. vulgaris is highly resistant to antibiotics because of the plasmids present in the bacterium, making infections extremely difficult to cure. This is because the plasmids have varied drug resistant markers on them.

Clinical expression

Enterobacterales (of which ''Proteus ''is a member) and ''Pseudomonas'' species are the micro-organisms most commonly responsible for Gram-negative bacteremia and sepsis. The presence of the sepsis syndrome associated with a urinary tract infection (UTI) should raise the possibility of urinary tract obstruction. This is especially true of patients who reside in long-term care facilities, who have long-term indwelling urethral catheters, or who have a known history of urethral anatomic abnormalities. ;UTI obstruction Urease production leads to precipitation of organic and inorganic compounds, which leads to struvite stone formation. Struvite stones are composed of a combination of magnesium ammonium phosphate (struvite) and calcium carbonate-apatite. Struvite stone formation can be sustained only when ammonia production is increased and the urine pH is elevated to decrease the solubility of phosphate. Both of these requirements can occur only when urine is infected with a urease-producing organism such as ''Proteus''. Urease metabolizes urea into ammonia and carbon dioxide: urea 2 NH₃ + CO₂. The ammonia/ammonium buffer pair has a pK of 9.0, resulting in the combination of highly alkaline, ammonia-rich urine. Symptoms attributable to struvite stones are uncommon. More often, women present with UTI, flank pain, or hematuria, and are found to have a persistently alkaline urine pH (>7.0).

Treatments

Antibiotics to which ''P. vulgaris'' is known to be sensitive: *

Ciprofloxacin Ciprofloxacin is a fluoroquinolone antibiotic used to treat a number of bacterial infections. This includes bone and joint infections, intra abdominal infections, certain types of infectious diarrhea, respiratory tract infections, skin inf ...

Ceftazidime Ceftazidime, sold under the brand name Fortaz among others, is a third-generation cephalosporin antibiotic useful for the treatment of a number of bacterial infections. Specifically it is used for joint infections, meningitis, pneumonia, sepsis, ...

* Netilmicin *

Sulbactam Sulbactam is a β-lactamase inhibitor. This drug is given in combination with β-lactam antibiotics to inhibit β-lactamase, an enzyme produced by bacteria that destroys the antibiotics. It was patented in 1977 and approved for medical use in ...

or cefoperazone *

Meropenem Meropenem, sold under the brand name Merrem among others, is an intravenous β-lactam antibiotic used to treat a variety of bacterial infections. Some of these include meningitis, intra-abdominal infection, pneumonia, sepsis, and anthrax. ...

* Piperacillin/tazobactam *

Ampicillin/sulbactam Ampicillin/sulbactam is a fixed-dose combination medication of the common penicillin-derived antibiotic ampicillin and sulbactam, an inhibitor of bacterial beta-lactamase. Two different forms of the drug exist. The first, developed in 1987 and ...

References

“Proteus Vulgaris.” Thistle, Thistle.co, www.thistle.co.za/pdf_files/education/microbiology/microbiology_legends/Cycle_41/Cycle%2041%20Organism%203%20-%20Proteus%20Vulgaris.pdf.

External links

Type strain of ''Proteus vulgaris'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
{{DEFAULTSORT:Proteus Vulgaris Bacteria described in 1885