The Role of Solvent-Accessible Leu-208 of Cold-Active Pseudomonas fluorescens Strain AMS8 Lipase in Interfacial Activation, Substrate Accessibility and Low-Molecular Weight Esterification in the Presence of Toluene.

ABSTRACT: The alkaline cold-active lipase from Pseudomonas fluorescens AMS8 undergoes major structural changes when reacted with hydrophobic organic solvents. In toluene, the AMS8 lipase catalytic region is exposed by the moving hydrophobic lid 2 (Glu-148 to Gly-167). Solvent-accessible surface area analysis revealed that Leu-208, which is located next to the nucleophilic Ser-207 has a focal function in influencing substrate accessibility and flexibility of the catalytic pocket. Based on molecular dynamic simulations, it was found that Leu-208 strongly facilitates the lid 2 opening via its side-chain. The K_M and K_cat/K_M of L208A mutant were substrate dependent as it preferred a smaller-chain ester (pNP-caprylate) as compared to medium (pNP-laurate) or long-cha

SUBMITTER: Yaacob N 

PROVIDER: S-EPMC6152135 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature