Molecular and Structural Characterizations of Lipases from Chlorella by Functional Genomics

Abstract

Microalgae have been poorly investigated for new-lipolytic enzymes of biotechnological interest. In silico study combining analysis of sequences homologies and bioinformatic tools allowed the identification and preliminary characterization of 14 putative lipases expressed by Chlorella vulagaris. These proteins have different molecular weights, subcellular localizations, low instability index range and at least 40% of sequence identity with other microalgal lipases. Sequence comparison indicated that the catalytic triad corresponded to residues Ser, Asp and His, with the nucleophilic residue Ser positioned within the consensus GXSXG pentapeptide. 3D models were generated using different approaches and templates and demonstrated that these putative enzymes share a similar core with common α/β hydrolases fold belonging to family 3 lipases and class GX. Six lipases were predicted to have a transmembrane domain and a lysosomal acid lipase was identified. A similar mammalian enzyme plays an important role in breaking down cholesteryl esters and triglycerides and its deficiency causes serious digestive problems in human. More structural insight would provide important information on the enzyme characteristics.

Bioinformatics-Based Screening Approach for the Identification and Characterization of Lipolytic Enzymes from the Marine Diatom Phaeodactylum tricornutum

“…For the class 3 lipase family, GHSLG (1523, Figure 1 B) is the most common pentapeptide motif, as already observed for lipases from fungi (e.g., Rhizomucor miehei ) [ 50 ], from the green microalga Chlorella sp. [ 51 ] and from the diatom Fistulifera solaris [ 52 ].…”

“…The higher MW obtained for P. tricornutum lipases could be explained by longer sequences with additional domains such as transmembrane domains, as reported for Chlorella sp. [ 51 ]. Independently of their families, the candidate lipases can also be separated into two major pI groups: an acidic one ranging from 5 to 6 and a basic one ranging from 8 to 10 ( Figure 2 A).…”

Ester Production Using the Lipid Composition of Coffee Ground Oil (Coffea arabica): A Theoretical Study of Eversa® Transform 2.0 Lipase as an Enzymatic Biocatalyst

“…The process of molecular coupling simulation was performed using the AutoDock Vina code (ver 1.2, California, CA, USA) [35] with rigid proteins and flexible ligands. A lattice configuration with enzyme active site parameters was set up for both calculations [36,37]. The software was used to evaluate the energy profiles of the ligand-receptor interactions.…”

Cold-Active Lipases and Esterases: A Review on Recombinant Overexpression and Other Essential Issues

“…The mechanism of the transesterification reaction of lipases is similar to their hydrolysis reaction mechanism as reviewed by Jegannathan, Abang [ 130 ]; the biocatalytic process involves a catalytic triad that serves as a charge-relay system, followed by the creation of an oxyanion hole and formation of tetrahedral intermediates. The catalytic triad of lipases and esterase is highly conserved regardless of whether they are of mesophilic, thermophilic, or psychrophilic origin [ 131 , 132 ]. Therefore, the focus is not on how they catalysed their reaction but on how they performed it in low temperatures in the case of cold-active enzymes.…”