Ranomics
Flow cytometry cell sorting equipment in a research laboratory
Capability

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 →
Overview

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.

Display formats

scFv, VHH, nanobody, and custom scaffold display

01

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.

02

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.

03

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.

04

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.

Selection

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.

MACS

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
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
Why yeast display

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.

FAQ

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.

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.

Start a project →