Fig. 6
Secretory expressions of lignocellulolytic enzymes in the cells with deletion of ESRTs. Secretory expression of AnFaeA (a), RuCelA (b) or Xyn-CDBFV (c) in the cells with deletion of ESRTs. ESR1, HRD3, YET3 or USA1 was deleted. A multi-copy plasmid overexpressing AnFaeA, RuCelA or XynCDB was transformed into deletion mutants. Extracellular activity in the supernatant was measured. The activity of AnFaeA, RuCelA or Xyn-CDBFV expressed by the wild-type strain was designated as unit 1. Value represented mean ± SD (n = 3) (*P < 0.05, **P < 0.01, ***P < 0.001). d Summary of effects of deletion of ESRTs. Data were extracted from (a ~ c) (*P < 0.05, **P < 0.01, ***P < 0.001). e Extracellular activities of AnFaeA and RuCelA in double-deletion mutants. The activity of AnFaeA or RuCelA expressed by the wild-type strain was designated as unit 1. Value represented mean ± SD (n = 3) (*P < 0.05, **P < 0.01). f Interaction between deletion of ESRTs. Trait value (T) was represented by the relative activity in the double or single deletion mutant compared with that in wild-type cells. The interaction value was calculated as TAB-TA-TB, where TAB represented the trait value of a double-deletion mutant, while TA and TB represented values of single mutants. Interaction values are shown in the chart. Values closing to zero indicated additive interactions and negative values indicated negative interactions. g–j Expression of Xyn-CDBFV or AnFaeA by wild-type and hrd3Δ cells in a 5-L fermentor. Cells were grown in the fermentor for 72 h. Curves of enzymatic activity and OD600 were plotted for cells expressing Xyn-CDBFV (g) and AnFaeA (i). SDS-PAGE analysis of 8 ul supernatant collected at indicated time point is shown in h, j. The arrow in j indicated the position of inulinase, which was a host protein secreted by K. marxianus [63]