Altering the Regioselectivity of T1 Lipase from Geobacillus zalihae toward sn-3 Acylglycerol Using a Rational Design Approach

The regioselectivity characteristic of lipases facilitate a wide range novel molecule unit constructions and fat modifications. Lipases can be categorized as sn-1,3, sn-2, random regiospecific. Geobacillus zalihae T1 lipase catalyzes the hydrolysis sn-1,3 acylglycerol chain. structural analysis shows that oxyanion hole F16 its lid domain undergo rearrangement upon activation. Site-directed mutagenesis was performed by substituting residues (F180G F181S) residue (F16W) in order to study their effects on changes regioselectivity. mutant 3M switches from only sn-3. shifts optimum pH 10, alters selectivity toward p-nitrophenyl ester C14-C18, maintains similar catalytic efficiency 518.4 × 10−6 (s−1/mM). secondary structure comprises 15.8% 26.3% α-helix β-sheet, respectively, with predicted melting temperature (Tm) value 67.8 °C. silico conducted reveal caused F180G/F181S/F16W mutations blocking binding sn-1 chain orientating substrate bond sn-3 acylglycerol, which resulted switching