Characterization of Novel Thermostable Lipase from Family I.5 expressed in Pichia pastoris: in vitro and in silico study Dimas Frananta Simatupang [a][b], Made Puspasari Widhiastuty [a], Fida Madayanti Warganegara [a], Akhmaloka [a]
[a] Biochemistry Division, Department of Chemistry, Institut Teknologi Bandung
[b] Department of Chemical Engineering, Politeknik Teknologi Kimia Industri Medan
Abstract
Itb1.1 was recombinant thermostable lipases from bacteria expressed in P. pastoris GS115 host cell extracellularly in a previous study. This research aimed to characterize a lipase in pure enzyme based on hydrolysis and transesterification activity. All experiments were investigated through the colorimetric method with slight modification to obtain optimum assay. The typical characteristics of Itb1.1 lipase was obtained that it worked well under optimum assay using medium-long acyl chains (C10), at temperatures 85 0C and pH 9.5 in alkaline condition. Furthermore, Itb1.1 lipase could maintain activity up to 50% for 4 h and tolerant in the presence of various organic solvents. The addition of Mg2+, Ca2+, Ni2+ and Fe2+ ions could enhance the activity of Itb1.1 lipase meanwhile the addition of Zn2+ ions inhibited its activity. This phenomenon revealed that Itb1.1 lipase was a unique and thought to be a novel lipase from Family I.5. This lipase was also stable in various surfactants. Moreover, transesterification activity was assessed to the thermostable lipase and revealed that Itb1.1 preferred medium-long chain fatty acid ester (C14:0). The in silico results were in agreement and supported with in vitro data. These results suggested that this lipase was potential biocatalyst for biodiesel production and various biotechnology applications.
