Bioinformatics and enzymatics investigation of Trametes laccase for optical biosensing application

摘要

Laccase has recently drawn a considerable attention as a promising tool for optical biosensing application, mainly due to its attractive intrinsic optical properties. The discovery of a laccase with great enzyme stability is the principal step for enzyme-based optical biosensing application in in vitro environments. In this paper, we found that Trametes sp. SQ1 laccase retained more than 150% activity after storage in different conditions for 96h, and the laccase activity was not affected by freeze-thaw. The reduced form of enzyme showed a new maximal increase in absorbance peak at 400nm, while the fluorescence intensity of the oxidized form of enzyme was much stronger than that of the reduced enzyme. Therefore, Trametes sp. SQ1 laccase with good stability and optical properties will be a competitive candidate for optical biosensing application. Moreover, bioinformatics analysis on Trametes laccases revealed that the enzymes may be modified by N-glycosylation and have intermolecular disulfide bond for forming functional oligomer, which plays a role in stabilizing enzyme function. The results indicate that Trametes laccases are able to be with good stability. It will provide a guide in searching stable laccases for optical biosensing application.