A novel thermostable and organic solvent-tolerant lipase from Xanthomonas oryzae pv. oryzae YB103: screening, purification and characterization.

Thermostable lipases offer major biotechnological advantages over mesophilic lipases. In this study, an intracellular thermostable and organic solvent-tolerant lipase-producing strain YB103 was isolated from soil samples and identified taxonomically as Xanthomonas oryzae pv. oryzae. The lipase from X. oryzae pv. oryzae YB103 (LipXO) was purified 101.1-fold to homogeneity with a specific activity of 373.9 U/mg. The purified lipase showed excellent thermostability, exhibiting 51.1% of its residual activity after incubation for 3 days at 70 °C. The enzyme showed optimal activity at 70 °C, suggesting it is a thermostable lipase. LipXO retained 75.1-154.1% of its original activity after incubation in 20% (v/v) hydrophobic organic solvents at 70 °C for 24 h. Furthermore, LipXO displayed excellent stereoselectivity (e.e.p >99%) toward (S)-1-phenethyl alcohol in n-hexane. These unique properties of LipXO make it promising as a biocatalyst for industrial processes.