Journal: iScience

Article Title: A functional surface display system in Saccharomyces boulardii for protein absorption in simulated intestinal fluids

doi: 10.1016/j.isci.2025.113303

Figure Lengend Snippet: S. boulardii strain generation (A) PCR verification of URA3 gene knockout ( URA3 Δ). This strain is derived from a commercial probiotic strain of S. boulardii (strain DBVPG 6763). The table gives a key indicating theoretical band sizes for each gene cassette amplified with the corresponding primer pair. A different antibiotic resistance cassette was used to knock out each URA3 allele. Both contain the Tef1 promoter and are of different sizes, indicated by two PCR products from the “TF” primer set in the figure. The second gel panel shows the absence of large molecular weight bands corresponding to antibiotic cassette elimination. (B) DNA gel showing removal of the plasmid containing the gene for Cre recombinase. (C) Graphic (SnapGene) illustrating the antibody surface display components using the anti-FAP example. AGA1 and AGA2 are the a-agglutinin genes, TEF1 and GAP ( TDH3 ) are the promoters, HA is the hemagluttinin tag, and scFv is the anti-FAP single-chain fragment variable antibody. (D) PCR verification of the antibody display cassette integration using primer pairs flanking the insertion region (XI-3 or XII-5). Control is the URA3 Δ strain from (A), and anti-FAP and anti-Lys are strains with integrated expression cassettes at the indicated chromosomal targets.

Article Snippet: Most studies utilize the MYA-796 strain of S. boulardii available from ATCC.

Techniques: Gene Knockout, Derivative Assay, Amplification, Knock-Out, Molecular Weight, Plasmid Preparation, Control, Expressing

Journal: iScience

Article Title: A functional surface display system in Saccharomyces boulardii for protein absorption in simulated intestinal fluids

doi: 10.1016/j.isci.2025.113303

Figure Lengend Snippet: Strain validation Each strain was sequenced with Oxford Nanopore Technology long-read sequencing and aligned to the S. cerevisiae S288C genome. Three genes were evaluated for mutations reported as genotypes unique to S. boulardii . Integrated Genomics Viewer was used to visualize the comparison with the reference S. cerevisiae genome. The nucleotide sequence at the bottom of each box represents the reference sequence. The horizontal gray bars represent a subset of sequencing reads for each sample. Red highlight indicates a mutation in the sequenced strand to thymine, orange to guanine, green to adenine, and blue to cytosine. The forward strand is shown in each case, meaning that the sense strand is represented for WHI2 and the antisense strand is represented for PGM2 and SDH1 . See also for sequence alignments of WHI2 , PGM2 , and SDH1 .

Article Snippet: Most studies utilize the MYA-796 strain of S. boulardii available from ATCC.

Techniques: Biomarker Discovery, Sequencing, Comparison, Mutagenesis

Journal: iScience

Article Title: A functional surface display system in Saccharomyces boulardii for protein absorption in simulated intestinal fluids

doi: 10.1016/j.isci.2025.113303

Figure Lengend Snippet: Antibody is functionally displayed on the surface of S . boulardii (A) Illustration (BioRender) of the yeast surface display system used in this study. The HA tag on the Aga2-antibody fusion protein is recognized by an anti-HA antibody labeled with a fluorophore, and the antigen (blue circle) is labeled with a different fluorophore. (B) Yeast cells displaying antibody by the Aga1/Aga2 system were treated with reducing agents, then the HA tag was probed and detected by flow cytometry to demonstrate the disulfide-dependent display of the fusion protein. (C) A western blot was performed on the parental strain and two strains containing genomic insertion of the surface display cassette to detect fusion protein expression (see for additional details). (D) Yeast cells with (anti-FAP and anti-Lys) or without (control) the antibody display cassette were evaluated by flow cytometry. (E) Confocal microscopy was used to visualize FAP and anti-HA binding to the anti-FAP strain. The white scale bars represent 10 μm in length.

Article Snippet: Most studies utilize the MYA-796 strain of S. boulardii available from ATCC.

Techniques: Labeling, Flow Cytometry, Western Blot, Expressing, Control, Confocal Microscopy, Binding Assay