Archives of Microbiology

, Volume 191, Issue 3, pp 233–240

Characterization of two soil metagenome-derived lipases with high specificity for p-nitrophenyl palmitate

Authors

    • Department of Basic MedicineTaishan Medical University
    • Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences and Peking Union Medical College
  • Wengang Song
    • Department of Basic MedicineTaishan Medical University
  • Gangping Hao
    • Department of Basic MedicineTaishan Medical University
Original Paper

DOI: 10.1007/s00203-008-0448-5

Cite this article as:
Wei, P., Bai, L., Song, W. et al. Arch Microbiol (2009) 191: 233. doi:10.1007/s00203-008-0448-5

Abstract

Two novel genes (pwtsB and pwtsC) encoding lipases were isolated by screening the soil metagenomic library. Sequence analysis revealed that pwtsB encodes a protein of 301 amino acids with a predicted molecular weight of 33 kDa, and pwtsC encodes a protein of 323 amino acids with a predicted molecular weight of 35 kDa. Furthermore, both genes were cloned and expressed in Escherichia coli BL21 (DE3) using pET expression system. The expressed recombinant enzymes were purified by Ni-nitrilotriacetic acid affinity chromatography and characterized by spectrophotometric with different p-nitrophenyl esters. The results showed that PWTSB displayed a high degree of activity and stability at 20°C with an optimal pH of around 8.0, and PWTSC at 40°C with an optimal pH of around 7.0. P-nitrophenyl palmitate (p-NPP) was identified as the best substrate of PWTSB and PWTSC. The specific activities of PWTSB and PWTSC were 150 and 166 U/mg, respectively toward p-NPP at 30°C, about 20-fold higher than that toward p-nitrophenyl butyrate (C4) and caprylate (C8). In conclusion, our results suggest that PWTSB is a cold adapt lipase and PWTSC is a thermostable lipase to long-chain p-nitrophenyl esters.

Keywords

LipaseMetagenomic libraryPWTSBPWTSC

Copyright information

© Springer-Verlag 2008