Morphological changes in Proteus mirabilis O18 biofilm under the influence of a urease inhibitor and a homoserine lactone derivative.
Proteus mirabilis is a pathogenic gram-negative bacterium that frequently causes kidney infections, typically established by ascending colonization of the urinary tract. The present study is focused on ureolytic activity and urease inhibition in biofilms generated by P. mirabilis O18 cells. Confocal microscopy revealed morphological alterations in biofilms treated with urea and a urease inhibitor (acetohydroxamic acid, AHA), as some swarmer cells were found to protrude from the biofilm. The presence of a quorum-sensing molecule (N-butanoyl homoserine lactone, BHL) increased biofilm thickness and its ureolytic activity. Laser interferometric determination of diffusion showed that urea easily diffuses through P. mirabilis biofilm, while AHA is blocked. This may suggest that the use of urease inhibitors in CAUTIs may by less effective than in other urease-associated infections. Spectroscopic studies revealed differences between biofilm and planktonic cells indicating that polysaccharides and nucleic acids are involved in extracellular matrix and biofilm formation.
Department of Microbiology, Jan Kochanowski University in Kielce, Świętokrzyska 15, 25-406, Kielce, Poland, gczerwonka@ujk.edu.pl.
Grzegorz
G
Czerwonka
Michał
M
Arabski
Sławomir
S
Wąsik
Agnieszka
A
Jabłońska-Wawrzycka
Patrycja
P
Rogala
Wiesław
W
Kaca
D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006877:Hydroxamic Acids / Q000494:pharmacology*; D011513:Proteus mirabilis / Q000187:drug effects* / Q000201:enzymology / Q000502:physiology*; D017550:Spectroscopy, Fourier Transform Infrared; D014508:Urea / Q000378:metabolism; D014510:Urease / Q000378:metabolism
D004791:Enzyme Inhibitors; D006877:Hydroxamic Acids; C088386:homoserine lactone; C006358:acetohydroxamic acid; D014508:Urea; D014510:Urease; D015107:4-Butyrolactone