Scientist I/II, Protein Expression and Purification

San Diego Stealth Startup; San Diego (CA); On-site; USD 90,000 - 120,000; Full time

Job summary

San Diego Stealth Startup in San Diego, CA is seeking a Scientist I/II, Enzyme Assay & Characterization to develop and execute biochemical assays for our multi-omics platform. You will optimize and implement assays and contribute to enzyme evaluation, enabling growth across assays, molecular biology, and protein engineering.

The role offers opportunities for cross-disciplinary growth and requires detail-oriented, analytical, and collaborative applicants who thrive in a fast-paced, innovative

Qualifications

• Bachelor’s or Master’s degree in Biochemistry, Molecular Biology, or Enzymology with relevant experience.
• Experience optimizing and implementing biochemical assays.
• Experience with spectroscopic and fluorescence-based assays.
• Gel electrophoresis experience.
• Strong data visualization skills.
• Excellent organization and communication.
• Ability to work independently and in cross-functional teams.

Responsibilities

• Clone, express, and screen protein constructs in bacterial expression systems.
• Optimize bacterial expression conditions.
• Execute purification workflows.
• Characterize protein quality.
• Optimize and implement biochemical assays.
• Develop, optimize, and validate spectroscopic and fluorescence-based assays.
• Troubleshoot and refine assays for reproducibility, sensitivity, and throughput.
• Collaborate with multiple teams (expression/purification, enzymology, engineering, molecular biology).
• Document methods, maintain records, contribute to SOPs and data summaries.

Skills

Biochemical assays

Spectroscopic assays

Fluorescence assays

Gel electrophoresis

Data visualization

Communication skills

Team collaboration

Independence

Education

B.S./M.S. in Biochemistry or related

Tools

Spectrophotometer

Fluorescence reader

Job description

Location: San Diego, CA

Job Type: Full-Time

Compensation: $90,000 to $120,000

Position Overview

We are seeking a Scientist I/II, Enzyme Assay & Characterization to play a key role in developing and executing biochemical assays that support the company’s multi-omics platform development. This individual will optimize and implement assays.

The Scientist I/II will contribute directly to enzyme evaluation. This role offers opportunities for broad technical growth, including assay development, molecular biology, protein engineering and integration.

The candidate must be detail-oriented, analytical, and collaborative, thriving in a dynamic environment that values innovation, cross-disciplinary interaction, and scientific rigor.

Key Responsibilities

• Clone, express, and screen protein constructs in bacterial expression systems.
• Optimize bacterial expression conditions.
• Execute purification workflows.
• Characterize protein quality.
• Optimize and implement biochemical assays.
• Develop, optimize, and validate spectroscopic and fluorescence-based assays.
• Troubleshoot and refine assays for reproducibility, sensitivity, and throughput.
• Collaborate closely with protein expression/purification, enzymology, protein engineering, and molecular biology teams.
• Document methods, maintain rigorous records, contribute to SOPs and prepare data summaries and reports.
• Support lab organization, maintain equipment, and ensure compliance with safety and reproducibility practices.

Qualifications

• B.S. in Biochemistry, Molecular Biology, Enzymology, or related field with 2–6 years of relevant experience, OR M.S. with 0–4 years of relevant experience. Level of position will depend on educational credential and years of experience.
• Demonstrated experience optimizing and implementing biochemical assays.
• Hands-on experience with spectroscopic and fluorescence-based assays.
• Hands-on experience with gel electrophoresis and gel-based assays.
• Strong experience with data visualization software.
• Excellent organizational, problem-solving, and communication skills.
• Ability to work independently and collaboratively in cross-functional teams.

Why Join Us

• Influence the foundational technologies and strategies of a company poised to shape the future of clinical genomics and healthcare.
• Work in a dynamic, collaborative environment where innovation and scientific rigor are deeply valued.
• Join a seasoned and multidisciplinary team tackling high-impact problems at the intersection of science and engineering.
• Competitive compensation and equity package, comprehensive benefits, and flexibility to support work-life integration.

We are an equal opportunity employer. We thrive on diversity and collaboration.