Cell-surface display of the active mannanase in Yarrowia lipolytica with a novel surface-display system

A novel surface-display system was constructed using the cell-wall anchor protein Flolp from Saccharomyces cerevisiae, the mannanase (man I) from Bacillus subtilis fused with the C-terminus of Flolp and the 6 x His tag was inserted between Flolp and manl. The fusion protein was displayed on the cell surface of Yarrowia lipolytica successfully, and it was confirmed by immunofluorescence. In succession, the surface-displayed mannanase was characterized. The optimum catalytic conditions for the recombinant mannanase were 55 degrees C at pH 6.0, and it exhibited high stability against pH variation. The highest activity of the recombinant mannanase reached 62.3 IU/g (dry cell weight) after the recombinant was cultivated for 96 h in YPD medium [1% (w/v) yeast extract/2% (w/v) peptone/2% (w/v) glucose]. To our knowledge, the present paper is the first to report that high-activity mannanase is displayed on the cell surface of Y. lipolytica with Flolp.