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Lipase activity from strains of Pasteurella multocida
J Pratt1, J D Cooley, C W Purdy
1Department of Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
Abstract:
Thirteen clinical isolates of Pasteurella multocida from a variety of different animals and humans were examined for their ability to produce lipase. Lipase substrates used included Tween 20, Tween 40, Tween 80, and Tween 85. Lipase activity was detected in the filtrates of organisms grown to the exponential phase in Roswell Park Memorial Institute-1640 defined media (RPMI-1640), but activity increased in the filtrates when the cultures were allowed to proceed to the stationary phase. All strains examined (except for serotype 2) showed lipase activity against at least one of the Tweens. Tween 40 was the best substrate to demonstrate lipase activity. Pasteurella multocida serotype 8 produced the most active lipase against Tween 40 (3,561.7 units of activity/microgram of protein). This activity continued to increase after P. multocida entered a stationary growth phase. P. multocida lipase activity was optimal at pH 8.0. Lipase activity of P. multocida serotype 8 was eluted from a Sepharose 2B column at several points, indicating that several lipases may be produced in vitro by this organism. These data demonstrate that clinical isolates of P. multocida produce lipase; therefore, this enzyme should be considered a potential virulence factors for this organism.
Insights
Clinical Pasteurella multocida isolates produce lipase, an enzyme that may contribute to the organism's virulence. Lipase activity was detected in most strains, with optimal production occurring in stationary phase cultures.
Area of Science:
- Microbiology
- Enzymology
- Bacteriology
Background:
- Pasteurella multocida is a significant pathogen affecting various animal species and humans.
- The role of microbial enzymes, such as lipase, in bacterial pathogenesis is an area of ongoing research.
- Understanding the enzymatic activity of P. multocida can provide insights into its virulence mechanisms.
Purpose of the Study:
- To investigate the lipase-producing capabilities of clinical isolates of Pasteurella multocida.
- To identify optimal conditions for lipase production and characterize the enzyme's activity.
- To evaluate lipase as a potential virulence factor in P. multocida infections.
Main Methods:
- Thirteen clinical isolates of P. multocida were cultured in Roswell Park Memorial Institute-1640 (RPMI-1640) media.
- Lipase activity was assessed using Tween 20, Tween 40, Tween 80, and Tween 85 as substrates.
- Enzyme activity was measured at different growth phases (exponential and stationary) and pH levels.
- Purification and characterization of lipase from P. multocida serotype 8 were performed using Sepharose 2B chromatography.
Main Results:
- Most P. multocida isolates (except serotype 2) exhibited lipase activity against at least one Tween substrate.
- Tween 40 proved to be the most effective substrate for detecting lipase activity.
- Lipase production increased significantly as cultures transitioned from exponential to stationary phase.
- P. multocida serotype 8 demonstrated the highest lipase activity, with optimal function at pH 8.0.
- Chromatographic analysis suggested the presence of multiple lipase enzymes produced in vitro.
Conclusions:
- Clinical isolates of Pasteurella multocida possess lipase-producing ability.
- Lipase activity is enhanced during the stationary growth phase and is pH-dependent.
- The presence of lipase in P. multocida isolates suggests its potential role as a virulence factor in disease pathogenesis.