Urease activity of Proteus penneri

Area of Science:

• Microbiology
• Enzymology
• Biochemistry

Background:

• Proteus penneri is a bacterial species known to possess urease activity.
• Urease enzymes are crucial in various biological processes and can contribute to conditions like urinary tract infections and stone formation.

Purpose of the Study:

• To characterize the urease activity of Proteus penneri strains.
• To investigate the enzymatic properties and inhibition of P. penneri urease.
• To assess the role of P. penneri urease in struvite crystal formation.

Main Methods:

• Urease activity assay on cell lysates.
• Native polyacrylamide gel electrophoresis (PAGE) to determine electrophoretic mobility.
• Enzyme characterization including molecular weight, isoelectric point, and Km determination.
• In vitro model of struvite formation using synthetic urine.

Main Results:

• P. penneri urease exhibited significant activity (4.9 ± 4.1 μmol NH3/min/mg protein) and was inducible by urea.
• Electrophoretic analysis revealed distinct mobilities compared to Providencia and Morganella ureases, with species-specific differences within Proteus.
• The enzyme had a molecular weight of ~246 kDa, pI of 5.1, and Km of 14 mM for urea.
• Acetohydroxamic acid, hydroxyurea, and EDTA inhibited urease activity.
• Acetohydroxamic acid effectively prevented struvite crystal formation in an in vitro model.

Conclusions:

• Proteus penneri possesses a distinct, inducible urease enzyme.
• Characterization provides insights into urease properties and potential inhibition strategies.
• P. penneri urease plays a role in struvite formation, which can be mitigated by inhibitors like acetohydroxamic acid.