Yeast surface display services
High-throughput yeast surface display CRO services for protein screening — scFv, VHH, nanobody, and custom scaffold libraries with FACS/MACS selection and NGS-resolved hit calling
Discuss your project →High-throughput protein screening using yeast surface display
Yeast surface display presents your protein of interest on the outer membrane of Saccharomyces cerevisiae, tethered via the Aga2p-Aga1p system. Each cell displays thousands of copies of a single variant, creating a direct genotype-phenotype linkage that survives multiple rounds of selection.
This linkage is the foundation of quantitative library screening. Cells expressing variants with desired properties — high binding affinity, improved stability, or enhanced expression — are enriched by fluorescence-activated cell sorting (FACS) or magnetic-activated cell sorting (MACS), then identified by next-generation sequencing.
scFv, VHH, nanobody, and custom scaffold display
scFv display
Single-chain variable fragments displayed as Aga2p fusions. Suitable for antibody discovery campaigns and affinity maturation of existing leads. Compatible with antigen-based FACS sorting and competition assays.
VHH and nanobody display
Camelid-derived single-domain antibodies are well-suited to yeast display due to their small size, high expression levels, and robust folding. Libraries from immunized or synthetic repertoires screened against soluble or cell-surface antigens.
Alternative scaffold display
DARPins, affibodies, fibronectin domains, and other non-immunoglobulin scaffolds displayed on yeast for target-specific selection. Custom surface expression constructs validated per scaffold class.
Computationally designed binder display
De novo binders generated by RFdiffusion, BindCraft, and Boltzgen, pooled as gene synthesis libraries, and screened on yeast for experimental validation of computational predictions. Couples design throughput to functional readout.
FACS and MACS selection strategies
Selection mode depends on library size, desired stringency, and the nature of your target. Most campaigns use MACS for initial enrichment followed by FACS for quantitative sorting.
Magnetic-activated cell sorting
High-throughput bulk enrichment using magnetic beads conjugated to your target antigen. Processes 10^8-10^9 cells per round. Ideal for removing non-binders from naive libraries in early rounds before transitioning to FACS.
- • Throughput: 10^9 cells per sort
- • Best for: initial library depletion
- • Typical rounds: 1-2 before FACS
Fluorescence-activated cell sorting
Quantitative single-cell sorting based on fluorescent labeling of target binding and surface expression. Enables gating on binding affinity normalized to expression level, multi-color sorting for specificity panels, and precise enrichment stringency control.
- • Throughput: 10^7 cells per sort
- • Best for: quantitative affinity discrimination
- • Typical rounds: 2-4 with increasing stringency
Advantages of yeast display for protein engineering
Eukaryotic folding and quality control
Yeast provides eukaryotic protein folding machinery, including the endoplasmic reticulum quality control pathway. Proteins that misfold are retained intracellularly, creating an inherent filter for well-folded, stable variants.
Quantitative, multi-parameter sorting
FACS enables simultaneous measurement of binding affinity and surface expression on each cell. Normalizing binding signal to expression level eliminates avidity artifacts and identifies true high-affinity clones.
Rapid library construction
High-efficiency yeast transformation yields libraries of 10^7 to 10^8 unique variants from electroporation of pooled DNA. Gap repair cloning allows seamless insertion of diversified regions without restriction enzymes.
Iterative selection cycles
Yeast cultures can be regrown between rounds of selection, enabling sequential enrichment under increasing stringency. This iterative process narrows libraries from millions of variants to tens of validated candidates.
Compatibility with NGS readout
Sorted populations are directly sequenced by next-generation sequencing to quantify enrichment ratios. Rank-ordered candidate lists replace qualitative colony-picking, providing statistically grounded hit calling.
Platform maturity and reproducibility
Yeast surface display is one of the most extensively validated directed evolution platforms. Two decades of published methodology and optimization provide a robust foundation for protein engineering campaigns.
See yeast display applied to a real client campaign
pH-dependent antibody engineering via yeast surface display
Six rounds of FACS selection on a 640-clone targeted mutagenesis library. Convergent hotspot residues and quantitative enrichment-score ranking from a real campaign.
Yeast display questions
What library sizes can yeast display handle? +
Our yeast display platform routinely handles libraries exceeding 10^8 transformants. Library diversity is confirmed by NGS before selection begins.
What protein formats can be displayed on yeast? +
scFv, VHH/nanobodies, miniproteins, Fab fragments, alternative scaffolds (DARPins, affibodies), and custom protein domains. We will advise on display construct design based on your format.
How do you select for binding affinity? +
We use FACS (fluorescence-activated cell sorting) with fluorescently labeled target at decreasing concentrations across 2-4 rounds. MACS (magnetic bead sorting) is used as a pre-enrichment step to deplete non-binders before FACS.
Can yeast display be used for non-antibody proteins? +
Yes. We display enzymes, receptor ectodomains, cytokines, and de novo designed binders. Any protein that can be expressed as a surface fusion on Aga2p is compatible with the platform.
Yeast display vs phage display — which should I use? +
Yeast display gives quantitative per-clone affinity readout via flow cytometry; phage display gives larger library size (10^11-10^12). For AI-designed or focused libraries that fit in 10^9, yeast is the better choice. For naive libraries needing maximum diversity, phage with a yeast follow-up is the standard pattern.
How does yeast display compare to mammalian display? +
Yeast is faster and cheaper but installs only high-mannose glycans. Mammalian display preserves complex glycosylation, full-length IgG assembly, and PTM-dependent epitopes. The standard workflow uses yeast for affinity discovery and mammalian display for developability validation downstream.
How are avidity artifacts handled in yeast display affinity measurements? +
Yeast displays each clone at 10,000-100,000 copies per cell, which can inflate apparent affinity by 100-1000x. We control for this by titrating display levels with anti-tag staining and normalizing binding signal to display intensity. For final lead validation, soluble protein affinity is measured by SPR or BLI.
Technical articles on yeast display
Yeast display for antibody discovery
Scaffold choices, library construction, MACS+FACS sorting, NGS hit calling, and developability triage.
Phage display vs yeast display
When to use which platform — library size, PTM fidelity, and quantitative readout trade-offs.
Yeast and mammalian display: two-platform approach
Use yeast for affinity discovery, mammalian for developability validation. Costs and timeline.
Yeast display library size: maximizing diversity
The practical ceiling at 10^9 transformants and what to do when the target needs more.
MACS pre-enrichment before FACS
How magnetic bead sorting reduces a 10^9 library to a FACS-sortable 10^7 in one step.
Avidity artifacts in yeast display
Why apparent affinity inflates 100-1000x on yeast and how to control for it during sorting.
Ready to screen your library?
Tell us about your target and library design. We will scope a yeast display campaign and return a timeline within 48 hours.
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