Computationally guided cell-free protein variant screening platform

Overview

This platform addresses the combinatorial bottleneck in protein engineering by combining computational design with automated cell-free expression and functional screening. It enables researchers to move from sequence hypotheses to testable proteins in days rather than weeks, while exploring a wider range of variants and conditions than conventional cell-based methods.

The approach starts with an experimental or predicted protein structure and uses structural context, evolutionary conservation, and stability modeling (e.g., FoldX) to prioritize candidate substitutions. Protein–ligand modeling is incorporated when relevant. The most promising variants are then arrayed into automated 96-well cell-free expression workflows, where they are synthesized, quality-checked, and functionally screened in parallel.

A key differentiator is the iterative design–build–test cycle: functional assay results feed back into the computational prioritization step, continuously refining variant selection and accelerating convergence toward improved proteins. This platform is applicable to enzyme engineering, therapeutic protein optimization, and other protein engineering efforts where speed and throughput are critical.

Technical specifications

Workflow components:

• Computational variant prioritization using structural context, evolutionary conservation, and stability prediction tools (e.g., FoldX)
• Optional protein–ligand interaction modeling for affinity or activity predictions
• Automated 96-well cell-free protein expression using commercial cell-free systems and liquid handling robotics
• Expression quality control and functional screening assays
• Iterative feedback loop connecting screening results to subsequent computational rounds

Operational advantages:

• Eliminates cloning, transformation, and cultivation bottlenecks from early screening
• Reduces cycle time and hands-on effort compared to conventional cell-based workflows
• Enables parallel testing of many variants and screening under diverse reaction conditions
• Scalable to larger variant libraries through automated liquid handling

Technology readiness level

The platform is in the early development stage (TRL 3–4). The computational prioritization workflow and automated cell-free expression system are being established, with validation focused on demonstrating reproducibility, yield, activity, and turnaround time improvements over conventional approaches. Future work will incorporate representative protein targets and assays to validate the workflow in a relevant discovery setting, with deliverables including validated automation protocols and performance data.