Catalytic characteristics of a sn‐1(3) regioselective lipase from Cordyceps militaris

Abstract

A total of 39 agricultural products were screened for natural sources of lipases with distinctive positional specificity. Based on this, Cordyceps militaris lipase (CML) was selected and subsequently purified by sequential chromatography involving anion‐exchange, hydrophobic‐interaction, and gel‐permeation columns. As a result of the overall purification procedure, a remarkable increase in the specific activity of the CML (4.733 U/mg protein) was achieved, with a yield of 2.47% (purification fold of 94.54). The purified CML has a monomeric structure with a molecular mass of approximately 62 kDa. It was further identified as a putative extracellular lipase from C. militaris by the partial sequence analysis using ESI‐Q‐TOF MS. In a kinetic study of the CML‐catalyzed hydrolysis, the values of Vmax, Km, and kcat were determined to be 4.86 μmol·min−1·mg−1, 0.07 mM, and 0.29 min−1, respectively. In particular, the relatively low Km value indicated that CML has a high affinity for its substrate. With regard to positional specificity, CML selectively cleaved triolein at the sn‐1 or 3 positions of glycerol backbone, releasing 1,2(2,3)‐diolein as the major products. Therefore, CML can be considered a distinctive biocatalyst with sn‐1(3) regioselectivity. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2744, 2019.

Integral Stereoselectivity of Lipase Based on the Chromatographic Resolution of Enantiomeric/Regioisomeric Diacylglycerols

“…The correlation between the DAG enantiomeric excess and the course of acylglycerol species according to the degree of hydrolysis provided several significant insights into integral stereoselectivity by considering the whole reaction process, including the acyl migration of DAG and MAG (Scheme ). No previous works reported strict stereoselectivity (100% enantiomeric excess) of lipase with TO as a substrate; however, several reports have suggested the potential of lipases with such stereoselectivity derived from fungal and microalgal sources. − This ambiguity could be clarified by determining the integral stereoselectivity of lipases based on the methodology used in this study. Also, the analytical system of the present study shows more complete description of the whole reaction process compared with the previous work on the analysis of gastric lipid digestion, which quantified DO and MO regioisomers without separation of 1,2- sn -DO and 2,3- sn -DO .…”

Hydrolysis of Edible Oils by Fungal Lipases: An Effective Tool to Produce Bioactive Extracts with Antioxidant and Antimicrobial Potential

“…Activity of lipases was evaluated against olive, linseed, peanut, grape seed, rapeseed, almond and menhaden fish oils in plate tests. Chromogenic plates were prepared based on the modified method of Singh et al [ 48 ] and Park et al [ 49 ] to detect the lipase activity of Chromobacterium viscosum and Cordyceps militaris . The methodology is based on the construction of a solid experimental system in Petri dish containing the corresponding oil substrate and a phenol red compound as indicator.…”

Lipase and Its Unique Selectivity: A Mini-Review

“…It is noteworthy that these two lipases have the potential to be further evolved into strictly sn-2 regioselective or sn-2 regiospeci c through advanced biotechnology. In addition, there are several reports on peculiar lipases, for example, an sn-1 (or sn-3) regioselective lipase from Cordyceps militaris, although more concrete evidence is needed [63].…”