Purification and Characterization of Pseudomonas aeruginosa PAO1 Asparaginase

The prevalence of bacterial infection has been gradually increased for the last decades. This phenomenon is predicted as one of serious problems to human security in the next decades. Helicobactorpylorihas been clarified to be related to gastric inflammation and a variety of diseases including gastric cancer. Recently, it has been known that H. pylori asparaginase is necessary for the growth in host infection and might be involved in inhibition of lymphocyte function at gastric niche. On the other hand, Pseudomonas aeruginosa is known to cause a fence-sitting infectious disease. However, no studies on a physiological role of asparaginase in relation to pathogenicity of P. aeruginosahave been found. Also, there are no studies on its physiological role in relation to pathogenicity of P. aeruginosa have been found. Therefore, we focused on purification and characterization of P. aeruginosaPAO1 asparaginase in order to clarify its physiological roles in this study. Intracellular asparaginase was highly purified and characterized from P. aeruginosa PAO1. The profile of DEAE-cellufine A 500 column chromatography suggested that two types of asparaginases were produced in P. aeruginosaPAO1. The optimum pH and temperature of the one enzyme was 9.5 and 40 °C, respectively while those of the another was 9.5 and 65 °C, respectively. Those results indicated that P. aeruginosa PAO1 had two different types of asparaginases.