Fig. 2
Analysis of sugar transport of TRE77517 in S. cerevisiae. a Prediction of the transmembrane region of TRE77517 through DeepTMHMM version 1.0.13 (https://dtu.biolib.com/DeepTMHMM). b Phylogenetic analysis of TRE77517 and selected sugar transporters. Alignments were conducted by ClustalW, and a phylogenetic tree was generated via MEGA-X software (Version 10.2.5) using the neighbor-joining method with 1000 bootstrap replications. c Subcellular location of TRE77517GFP in S. cerevisiae. Yeast strains expressing GFP-tagged TRE77517 under strong constitutive promoter Ptpi were cultured in SC medium with 2% maltose as carbon source for 16 h before microscopy analysis. Images was captured with a 63 × oil objective, and the scale bar represents 5 μm. d Analysis of sugar transport in S. cerevisiae. The yeast EBY.VW4000 coexpressing the β-glucosidases gh1-1 and TRE77517 were precultured on SC medium with maltose as the carbon source. Cells were harvested and washed twice, tenfold serial dilution was applied, and 5 μL suspension was dropped on the SC plate with maltose, glucose, cellobiose or lactose as the carbon source. The strains on maltose plate were incubated at 30 °C for 3 days. 5 days were applied for strains on glucose, cellobiose and lactose SC plate. The empty plasmid pYX212 was used as a negative control, and a strain harboring the cellobiose transporter CRT1 was used as a positive control. e Equal amounts of yeast strains (OD600 = 30) were mixed with 200 μM sugar and incubated at 30 °C at 200 rpm for 40 min. The residual sugar in yeast with empty plasmid was normalized as 100%. Residual sugar was analyzed by HPAEC. n.d. for not detected