Title: Functional characterization of hormone sensitive-like lipase from Bacillus halodurans: synthesis and recovery of pNP-laurate with high yields Dua A, Gupta R Ref: Extremophiles, 21:871, 2017 : PubMed
The HSL-like lipase encoding gene (Blip) from the polyextremophile Bacillus halodurans C-125 has been heterologously expressed in E.coli BL21(DE3). The enzyme is a monomer of ~42 kDa. It has extremely high thermal stability with a t 1/2 of 35 min at 100 degrees C. Thermal denaturation/renaturation studies by CD and fluorescence analysis revealed complete refolding of the protein back to its native conformation even after 30 min at 90 degrees C. Blip prefers substrates with mid to long chain fatty acids. It has a higher catalytic efficiency on para-nitrophenyl fatty acyl esters as opposed to triacylglycerides (k cat/K m with pNP-palmitate as a substrate was 2.52 x 10(5) mM(-1) min(-1) while that with glyceryl tripalmitin was 4.06 x 10(2) mM(-1) min(-1), respectively). The enzyme also has a unique selectivity for hydrolysis of unsaturated fatty acyl esters. The enzyme catalyses the synthesis of pNP-laurate with an optimized conversion of 95.94 +/- 0.24%. A simple procedure for purification of the product has been developed that led to 89.91 +/- 0.33% product recovery.
Dua A, Gupta R (2017) Functional characterization of hormone sensitive-like lipase from Bacillus halodurans: synthesis and recovery of pNP-laurate with high yields Extremophiles21: 871-889