Lipases are important industrial enzymes. Most of the lipases operate at lipid–water interfaces enabled by a mobile lid domain located over the active site. Lid protects the active site and hence responsible for catalytic activity. In pure aqueous media, the lid is predominantly closed, whereas in the presence of a hydrophobic layer, it is partially opened. Hence, the lid controls the enzyme activity. In the present review, we have classified lipases into different groups based on the structure of lid domains. It has been observed that thermostable lipases contain larger lid domains with two or more helices, whereas mesophilic lipases tend to have smaller lids in the form of a loop or a helix. Recent developments in lipase engineering addressing the lid regions are critically reviewed here. After on, the dramatic changes in substrate selectivity, activity, and thermostability have been reported. Furthermore, improved computational models can now rationalize these observations by relating it to the mobility of the lid domain. In this contribution, we summarized and critically evaluated the most recent developments in experimental and computational research on lipase lids.
Peroxygenases are promising catalysts for preparative oxyfunctionalization chemistry as they combine the versatility of P450 monooxygenases with simplicity of cofactor-independent enzymes. Though many interesting applications have been reported, today 'we have only scratched the surface' and significant efforts are necessary to solve issues related to selectivity of the wild type enzymes and low product titers. For this, further elucidation of the vast natural diversity as well as protein and reaction engineering approaches are discussed.
One of the major challenges in the upgrading of high-acid rice bran oil (RBO) is to efficiently reduce the amount of free fatty acids. Here we report a novel method for upgrading high-acid RBO using ethanol as a novel acyl acceptor in combination with a highly selective lipase from Malassezia globosa (SMG1-F278N). This process enabled an unprecedented deacidification efficiency of up to 99.80% in a short time (6 h); the immobilized SMG1-F278N used in deacidification exhibited excellent operational stability and could be used for at least 10 consecutive batches without detectable loss in activity. Scale-up was performed under optimized conditions to verify the applicability of this process, and low-acid (0.08%) RBO with a high level of γ-oryzanol (27.8 g/kg) and γ-oryzanol accumulation fold (1.5) was obtained after molecular distillation at lower temperature (120 °C). Overall, we report a simplified and efficient procedure for the production of edible RBO from high-acid RBO.
Phospholipase B (EC 3.1.1.5) are a distinctive group of enzymes that catalyzes the hydrolysis of fatty acids esterified at the sn-1 and sn-2 positions forming free fatty acids and lysophospholipids. The structural information and catalytic mechanism of phospholipase B are still not clear. Herein, we reported a putative phospholipase B (TmPLB1) from Talaromyces marneffei GD-0079 synthesized by genome mining library. The gene (TmPlb1) was expressed and the TmPLB1 was purified using E. coli shuffle T7 expression system. The putative TmPLB1 was purified by affinity chromatography with a yield of 13.5%. The TmPLB1 showed optimum activity at 35 °C and pH 7.0. The TmPLB1 showed enzymatic activity using Lecithin (soybean > 98% pure), and the hydrolysis of TmPLB1 by 31P NMR showed phosphatidylcholine (PC) as a major phospholipid along with lyso-phospholipids (1-LPC and 2-LPC) and some minor phospholipids. The molecular modeling studies indicate that its active site pocket contains Ser125, Asp183 and His215 as the catalytic triad. The structure dynamics and simulations results explained the conformational changes associated with different environmental conditions. This is the first report on biochemical characterization and structure dynamics of TmPLB1 enzyme. The present study could be helpful to utilize TmPLB1 in food industry for the determination of food components containing phosphorus. Additionally, such enzyme could also be useful in Industry for the modifications of phospholipids.
Deep eutectic solvents (DESs) are a mixture of hydrogen bond donor (HBD) and hydrogen bond acceptor (HBA) molecules that can consist, respectively, of natural plant metabolites such as sugars, carboxylic acids, amino acids, and ionic molecules, which are for the vast majority ammonium salts. Media such as DESs are modular tools of sustainability that can be pointed toward the extraction of bioactive molecules due to their excellent physicochemical properties, their relatively low price, and accessibility. The present review focuses on the application of DESs for protein extraction and purification. The in-depth effects and principles that apply to DES-mediated extraction using various renewable biomasses will be discussed as well. One of the most important observations being made is that DESs have a clear ability to maintain the biological and/or functional activity of the extracted proteins, as well as increase their stability compared to traditional solvents. They demonstrate true potential for a reproducible but more importantly, scalable protein extraction and purification compared to traditional methods while enabling waste valorization in some particular cases.
150 °C) and highly pure (99.85%) TAG with 88.73% n-3 PUFA was obtained. The final glyceride mixtures with low acid, peroxide and anisidine value were promising products for medical and dietetic purposes. Compared with the conventional one-step synthesis of n-3 PUFA-enriched TAG by enzymatic esterification or glycerolysis or the twostep method by combined transesterification and ethanolysis, this improved process allows for higher purity of n-3 PUFA-enriched TAG and significant reduction in reaction time.Abstract Highly pure n-3 polyunsaturated fatty acids (PUFA)-enriched triacylglycerols (TAG) have attracted considerable attention due to their nutritional benefits and pharmacological effects. In this study, an alternative approach to the conventional method for the synthesis of highly pure n-3 PUFA-enriched TAG by using a multi-step process was reported. First, glyceride mixtures were synthesized through Novozym 435 [Novozymes A/S (Bagsvaerd, Denmark)] catalyzed esterification of n-3 PUFAenriched FA and glycerol. Second, partial glycerides in the resulting glyceride mixtures were hydrolyzed to FA by immobilized partial glycerides-selective lipase from Malassezia globosa. The purity of TAG reached 99.84% under the optimized conditions: buffer solution of pH 6.0, water content of 100% (w/w, with respect to the oil mass), enzyme loading of 120 U/g (U/w, with respect to oil mass) and reaction temperature of 30 °C. During hydrolysis, the immobilized SMG1-F278N exhibited good reusability and TAG purity of over 94% was maintained after being used for six cycles. Subsequently, purification of TAG was accomplished by molecular distillation at low temperature
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.