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Various intensity of Proteus mirabilis-induced crystallization resulting from the changes in the mineral composition of urine

100%

Torzewska A., Różalski A.

issue 1

127-132

Infectious urolithiasis is a result of recurrent and chronic urinary tract infections caused by urease-positive bacteria, especially Proteus mirabilis. The main role in the development of this kind of stones is played by bacterial factors such as urease and extracellular polysaccharides, but urinary tract environment also contributes to this process. We used an in vitro model to establish how the changes in the basic minerals concentrations affect the intensity of crystallization which occurs in urine. In each experiment crystallization was induced by an addition of P. mirabilis to artificial urine with a precisely defined chemical composition. Crystallization intensity was determined using the spectrophotometric microdilution method and the chemical composition of formed crystals was established by atomic absorption spectroscopy and colorimetric methods. Increasing the concentration of all crystals forming ions such as Mg2+, Ca2+ and phosphate strongly intensified the process of crystallization, whereas reducing the amount of these components below the proper physiological concentration did not affect its intensity. The inhibitory influence of citrate on calcium and magnesium phosphate crystallization and competitive actions of calcium and oxalate ions on struvite crystals formation were not confirmed. In the case of infectious stones the chemical composition of urine plays an important role, which creates a necessity to support the treatment by developing a model of proper diet.

Proteus sp. – an opportunistic bacterial pathogen – classification, swarming growth, clinical significance and virulence factors

42%

Różalski A., Torzewska A., Moryl M., Kwil I., Maszewska A., Ostrowska K., Drzewiecka D., Zabłotni A., Palusiak A., Siwińska M., Stączek P.

Acta Universitatis Lodziensis. Folia Biologica et Oecologica

2012

vol. 8

1-17

The genus Proteus belongs to the Enterobacteriaceae family, where it is placed in the tribe Proteeae, together with the genera Morganella and Providencia. Currently, the genus Proteus consists of five species: P. mirabilis, P. vulgaris, P. penneri, P. hauseri and P. myxofaciens, as well as three unnamed Proteus genomospecies. The most defining characteristic of Proteus bacteria is a swarming phenomenon, a multicellular differentiation process of short rods to elongated swarmer cells. It allows population of bacteria to migrate on solid surface. Proteus bacteria inhabit the environment and are also present in the intestines of humans and animals. These microorganisms under favorable conditions cause a number of infections including urinary tract infections (UTIs), wound infections, meningitis in neonates or infants and rheumatoid arthritis. Therefore, Proteus is known as a bacterial opportunistic pathogen. It causes complicated UTIs with a higher frequency, compared to other uropathogens. Proteus infections are accompanied by a formation of urinary stones, containing struvite and carbonate apatite. The virulence of Proteus rods has been related to several factors including fimbriae, flagella, enzymes (urease - hydrolyzing urea to CO2 and NH3, proteases degrading antibodies, tissue matrix proteins and proteins of the complement system), iron acqusition systems and toxins: hemolysins, Proteus toxin agglutinin (Pta), as well as an endotoxin - lipopolysaccharide (LPS). Proteus rods form biofilm, particularly on the surface of urinary catheters, which can lead to serious consequences for patients. In this review we present factors involved in the regulation of swarming phenomenon, discuss the role of particular pathogenic features of Proteus spp., and characterize biofilm formation by these bacteria.

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1 Acta Biochimica Polonica

1 Acta Universitatis Lodziensis. Folia Biologica et Oecologica

1 2015

1 2012

2 Różalski A.

2 Torzewska A.

1 Drzewiecka D.

1 Kwil I.

1 Maszewska A.

1 Moryl M.

1 Ostrowska K.

1 Palusiak A.

1 Siwińska M.

1 Stączek P.

1 Zabłotni A.

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Various intensity of Proteus mirabilis-induced crystallization resulting from the changes in the mineral composition of urine

Proteus sp. – an opportunistic bacterial pathogen – classification, swarming growth, clinical significance and virulence factors