초록
<P><B>Abstract</B></P> <P>Yeast cell-surface display is an efficient and cost-effective technology to produce recyclable whole-cell biocatalysts for numerous industrial applications. In this study, the optimized lipase 1 gene from <I>Candida rugosa</I> (CRL1) was displayed, for the first time, on the cell wall of <I>Pichia pastoris</I> using a truncated flocculation functional domain of Flo1p (FS) anchor. The hydrolytic activity of displayed CRL1 reached 7517 U/g under the control of the AOX1 promoter. Higher lipase activity, 19,771 U/g (an increase of 163%), was obtained by a five-copy CRL1 construct overexpressing the HAC1 factor. Flow cytometry and quantitative analysis demonstrated the CRL1 was successfully displayed on the yeast surface with high efficiency. Displayed CRL1 was characterized by the optimal temperature and pH at 50℃ and 8.5, respectively; the half-life was both 6 h under the optimal temperature and pH8.0. Displayed CRL1 also exhibited remarkable stability in the presence of different organic solvents, surfactants, and metal ions. A 3-L fed-batch fermentation confirmed the reproducibility of yeast-displayed CRL1 in large-scale production. Taken together, these findings provide a novel recyclable whole-cell biocatalyst, which not only had a high lipase activity but also with superior characteristics over free lipase, indicating great potential for further application.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Lipase 1 from <I>C. rugosa</I> was first displayed on the cell surface of <I>P. pastoris</I>. </LI> <LI> 163% higher lipase activity (19,771 U/g) was realized via combined strategies. </LI> <LI> The high display efficiency of CRL1 was confirmed by multiple types of analysis. </LI> <LI> The remarkable stability of displayed CRL1 was verified in different conditions. </LI> </UL> </P>