Protein Engineer

Until is a moonshot company building a “pause button” for biology. Our near-term focus is organ-scale reversible cryopreservation: preserving donated organs at subzero temperatures without ice formation, then rewarming them uniformly for transplant. By solving this grand challenge, we’re laying the foundation for whole-body reversible cryopreservation, giving patients a bridge to future cures.

To achieve our goal, we are assembling an interdisciplinary team to develop perfusion systems, cryoprotectant formulations, and vitrification and rewarming hardware.

We envision a future where no transplantable organ is lost to logistics, and no terminal diagnosis is final because patients can safely wait for future medicine to arrive.

About the Role

You will play a crucial role in advancing cryopreservation formulations through the discovery of new biomolecules (proteins, peptides, biopolymers) that prevent ice formation. You will focus on building machine learning models to predict new ice blockers and their expression in host cells. You will also apply protein engineering and synthetic biology approaches to build plasmids, engineer strains, express biomolecules and analyze their ice blocking properties. This role will closely interact with the high throughput screening team to scale the testing of the new biomolecules across cells, 3D in vitro models, and tissues. This role requires a balance of technical expertise and creative problem solving.

• Use innovative approaches to discover and characterize new biomaterials (anti-freeze proteins, peptides, biopolymers).
• Train and evaluate machine learning models to predict new biomaterials to prevent ice formation, engineer expression hosts to produce them, and test their activity.
• Closely collaborate with high throughput screening team to evaluate new biomaterials at preventing ice formation.
• Effectively communicate analysis results to an interdisciplinary team

• Expertise in strain and genome engineering, cloning, protein engineering, and protein expression.
• Proficiency with advanced microscopy methods, including IHC, time-lapse imaging, TIRF, and super-resolution/light-sheet microscopy.

• 4+ years of industry experience or PhD/Postdoc training in Bioengineering, Computational Biology, Synthetic Biology, or a related field.
• Experience in computational biology and machine learning-based approaches to predict new biomolecules, their activity, and expression in expression hosts.
• High competence with Python and standard deep learning frameworks.
• Expertise in engineering expression hosts (bacteria, yeast, and mammalian cells) to produce proteins, purify them, and assess stability and activity through functional assays.
•  Track record of scientific excellence and autonomy.
• You bring a collaborative mindset and value diverse perspectives.

• Direct impact in a moonshot company creating the future as an early team member.
• Generous medical, dental and vision insurance coverage.
• Flexible time off and paid holidays.
• Competitive compensation package, including salary and equity.
• Access to a 401(k) retirement savings plan.
• FSA and commuter benefits.
• Subsidized lunch daily.

As an equal opportunity employer, Until is committed to providing employment opportunities to all individuals. All applicants for positions at Until will be treated without regard to race, color, ethnicity, religion, sex, gender, gender identity and expression, sexual orientation, national origin, disability, age, marital status, veteran status, pregnancy, or any other basis prohibited by applicable law.