Study the effect of F17S mutation on the chimeric Bacillus thermocatenulatus lipase

Lipases (triacylglycerol acylhydrolase, EC 3.1.1.3) are one of the highest value commercial enzymes as they have potential applications in biotechnology for detergents, food, pharmaceuticals, leather, textiles, cosmetics, and paper industries; and are currently receiving considerable attention because of their potential applications in biotechnology. Bacillus thermocatenulatus Lipase 2 (BTL2) is one of the most important research targets, because of its potential industrial applications. In this study, the effect of substitution Phe17 with Ser in mutated BTL2 lipase, which conserved pentapeptide (112Ala-His-Ser-Gln-Gly116) was replaced with similar sequences (207Gly-Glu-Ser-Ala-Gly211) of Candida rugosa lipase (CLR) at the nucleophilic elbow region. Docking results confirmed the mutated lipase to be better than the chimeric lipase. So, cloning was conducted, and the mutated and chimeric btl2 genes were expressed in Escherichia coli, and then the enzymes were purified by anion exchange chromatography. The mutation increased lipase lipolytic activity against most of the applied substrates, with the exception of tributyrin when compared with chimeric lipase. Further, the mutated lipase exhibited higher activity than the chimeric lipase at all temperatures. Optimum pH of the mutated lipase was obtained at pH 9.5, which was more than the chimeric one. Enzyme activity of the mutated lipase in the presence of organic solvents, detergents, and metal ions was also improved than the chimeric lipase

A facile and cost-effective method for simultaneous preparation of lectin and tyrosinase from edible mushroom

<p><i>Agaricus bisporus</i> is a safe and rich source of tyrosinase and lectin. To address the increasing demand for these proteins, a facile method was developed for their simultaneous preparation from <i>A. bisporus</i>. The method includes demelanization of the raw extract followed by stepwise precipitation of the proteins from the aqueous extract. Employing the right organic solvent in demelanization and precipitation steps reduces the intermolecular interactions between these proteins. This enhances the efficacy of gel-permeation chromatography and results in preparation of partially purified lectin and tyrosinase suitable for many applications in biotechnology and bio-research. The method can be performed without diafiltration.</p