Kinetic constraints and features imposed by the immobilization of enzymes onto solid matrices: A key to advanced biotransformation

1045-1051The kinetics of immobilized enzymes can not be analyzed by means of the simple Michaelis-Menten concept, which generally fails to describe the immobilized state due to both its probable barriers, and because the active concentration of the enzyme approaches, or even exceeds this of its substrate(s). In such cases, the various experimental data are usually treated by complex rate equations comprising too many parameters acquiring different natures and meanings, depending on both the properties of the immobilization state and the experimental conditions; thus, more likely, only apparent values of the Michaelis-Menten kinetic parameters can be estimated experimentally. Likewise, immobilization is often a key method in optimizing the operational performance of enzymes, in both laboratory and industrial scale, and affects considerably the kinetics in non-aqueous and non-conventional media due to several issues as the structural changes of the enzyme molecule, the heterogeneity of the system, and the partial or total absence of water. In this work a theoretical approach is described on the formulation of simplified rate equations, reflecting also the actual mass balances of the reactants, in the case where esterification synthetic reactions are catalyzed by immobilized lipases, in either a non-aqueous organic solvent or in a non-solvent system

Correction to: Molecular, biochemical and kinetic analysis of a novel, thermostable lipase (LipSm) from Stenotrophomonas maltophilia Psi‑1, the first member of a new bacterial lipase family (XIX)

We have recently (8th February 2018) published our article entitled “Molecular, biochemical and kinetic analysis of a novel, thermostable lipase (LipSm) from Stenotrophomonas maltophilia Psi-1, the first member of a new bacterial lipase family (XVIII)” [1]. While our manuscript was going through the final stages of publication, an article by Samoylova et al. [2] was published (12th January 2018) in the journal Extremophiles, entitled “Cloning, expression and characterization of the esterase estUT1 from Ureibacillus thermosphaericus which belongs to a new lipase family XVIII”. Since we could not have known of the work of Samoylova et al. [2] when we submitted our manuscript, and in order to avoid confusion in the scientific community, we propose to reclassify LipSm as the first characterized member of the new bacterial lipase family XIX. Therefore throughout our article [1] “lipase family XVIII” should read “lipase family XIX” (title included)