Applied Biochemistry and Biotechnology

, Volume 151, Issue 2–3, pp 160–166 | Cite as

Protein-Coated Microcrystals of Pseudomonas aeruginosa PseA lipase

  • Ruchi Gaur
  • G. N. Gupta
  • M. Vamsikrishnan
  • S. K. KhareEmail author


Highly active Pseudomonas aeruginosa lipase protein-coated microcrystals (PAL PCMC) have been prepared by immobilization of protein onto K2SO4 as excipient solid support carrier and n-propanol as precipitating solvent. Transmission electron micrographs confirmed the formation of PAL PCMC. These PCMC were found to be a catalytically more active and stable preparation for p-nitrophenyl palmitate hydrolysis in n-heptane, compared to free lipase. The V max, K m, and temperature optimum for PAL PCMC increased from 0.49 to 5.66 nmol min−1 mg−1, 589 to 679.8 mmol, and 40°C to 45°C, respectively. These were thermally more stable with 4.65, 2.56, and 1.24-fold improvement in half lives at 45°C, 55°C, and 60°C compared to free P. aeruginosa PseA lipase. Their catalytic efficiency was enhanced by tenfold over that of free enzyme. PAL PCMC offer a simple and effective technique for obtaining stable and efficient lipase preparation for biocatalysis in nonaqueous medium.


Pseudomonas aeruginosa Protein-coated microcrystals (PCMC) Lipase Immobilization Nonaqueous medium 



The financial support granted by Department of Biotechnology (DBT), Department of Science and Technology (DST) and Ministry of Human Resource Development (MHRD), Govt. of India, is gratefully acknowledged. Authors are thankful to Council for Scientific and Industrial Research (CSIR), Govt. of India, and IIT Delhi for research fellowship.


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Copyright information

© Humana Press 2008

Authors and Affiliations

  • Ruchi Gaur
    • 1
  • G. N. Gupta
    • 1
  • M. Vamsikrishnan
    • 1
  • S. K. Khare
    • 1
    Email author
  1. 1.Chemistry DepartmentIndian Institute of TechnologyNew DelhiIndia

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