QSAR study and the hydrolysis activity prediction of three alkaline lipases from different lipase-producing microorganisms

Haikuan Wang,Changlu Guo,Heng Zheng,Yehong Zhang,Yujie Dai,Xiaojie Wang,Xiaolu Li

doi:10.1186/1476-511x-11-124

Abstract

The hydrolysis activities of three alkaline lipases, L-A1, L-A2 and L-A3 secreted by different lipase-producing microorganisms isolated from the Bay of Bohai, P. R. China were characterized with 16 kinds of esters. It was found that all the lipases have the ability to catalyze the hydrolysis of the glycerides, methyl esters, ethyl esters, especially for triglycerides, which shows that they have broad substrate spectra, and this property is very important for them to be used in detergent industry. Three QSAR models were built for L-A1, L-A2 and L-A3 respectively with GFA using Discovery studio 2.1. The models equations 1, 2 and 3 can explain 95.80%, 97.45% and 97.09% of the variances (R2adj) respectively while they could predict 95.44%, 89.61% and 93.41% of the variances (R2cv) respectively. With these models the hydrolysis activities of these lipases to mixed esters were predicted and the result showed that the predicted values are in good agreement with the measured values, which indicates that this method can be used as a simple tool to predict the lipase activities for single or mixed esters.

Highlights

Lipases are defined as triacylglycerol acylhydrolases (E.C. 3.1.1.3) that catalyze the hydrolysis of oils and fats at the oil–water interface to free fatty acids and glycerol
In order to systematic evaluate its ability to hydrolyze different esters including some usually existed in edible oils and fats, this study derived some quantitative structure and activity relationships (QSARs) between the experimental results and structural parameters important for the substrate specificity of Burkholderia cepacia L-A1, Acinetobacter johnsonii L-A2 and Acinetobacter calcoaceticus L-A3 towards triglyceride, ethyl oleate, methyl laurate and allyl phenylacetate, etc
Because the descriptor number available normally exceeds that of the samples, how to prevent over-fitting of genetic function approximation (GFA) is critical to the successful construction of a statistically significant QSAR model

Summary

Introduction

Lipases are defined as triacylglycerol acylhydrolases (E.C. 3.1.1.3) that catalyze the hydrolysis of oils and fats at the oil–water interface to free fatty acids and glycerol. The other reason is that the substrates in detergency ability evaluation are different from that in the determination of lipase activities [14]. In the washing performance evaluation, the substrates used are usually mixture of different fats or oil, for example, lipase decontamination capability was measured using emulsified olive oil as the substrate [15,16]. There are few reports on the systematic evaluation of the lipase detergency ability using different substrates existed in oil spill. In order to systematic evaluate its ability to hydrolyze different esters including some usually existed in edible oils and fats, this study derived some quantitative structure and activity relationships (QSARs) between the experimental results and structural parameters important for the substrate specificity of Burkholderia cepacia L-A1, Acinetobacter johnsonii L-A2 and Acinetobacter calcoaceticus L-A3 towards triglyceride, ethyl oleate, methyl laurate and allyl phenylacetate, etc. This study will be useful for developing a standard for lipase evaluation with their detergency ability

Materials and methods

Results and discussion

Conclusion

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