Senior Scientist
- United States - California - San Diego
Pfizer Worldwide Research & Development, La Jolla, CA
Pfizer Worldwide Research and Development in La Jolla, CA is seeking a highly motivated scientist to join the Structural Biology and Protein Sciences (SBPS) Group within the Department of Oncology Medicinal Chemistry. The SBPS mission is to enable oncology drug discovery through expert protein production, biophysical interrogation, and structure-based insight, delivering high quality protein tools and data required to accelerate medicinal chemistry and translational decisions. The position will primarily support the small molecule portfolio, with opportunities to enable emerging targets and novel therapeutic modalities.
Role Responsibilities
This position is laboratory-based and best suited for an experimental scientist with deep expertise in protein expression, purification, biophysical characterization, and crystallization of challenging targets. The successful candidate for this position will:
- Work under supervision as a technical expert in the gene-to-structure pipeline, from construct design and expression through advanced purification, biophysical characterization, high-throughput crystallization and orthologous structure enablement including sample and grid preparation to enable cryo-EM.
- Support multiple small molecule oncology drug discovery programs in parallel.
- Collaborate with colleagues in Structural Biology and Protein Sciences, Medicinal Chemistry, Biophysics, Enzymology and Computational Chemistry, serving as protein sciences and structural biology resource on multidisciplinary teams and providing clear data, troubleshooting, and high-quality experimental insight to enable rapid decision making.
- Identify and integrate emerging protein and structural biology technologies to strengthen current capabilities within the group.
Required Qualifications
- B.S., M.S., or Ph.D. (or equivalent) in Biochemistry, Structural Biology, Protein Sciences or a related discipline, with 9+ years of relevant experience for a Bachelor’s degree, 7+ years for a Master’s degree, or 0+ years' experience required for a Ph.D.
- Extensive hands‑on laboratory experience in advanced protein biochemistry, with a proven track record of producing high‑quality protein samples from exceptionally challenging targets for structural and biophysical studies.
- Expertise in protein construct design, expression across multiple systems, and complex, multi‑step purification workflows, including development of fit‑for‑purpose proteins to support crystallography, structure‑based drug discovery, biochemical assays and hit identification screens
- Strong background in biophysical characterization (e.g., stability, oligomeric state, SPR, ITC, BLI) to assess protein quality and guide construct, purification, and ligand strategies.
- Hands‑on experience in protein crystallization and small‑molecule co‑crystallization, including condition screening, optimization, and crystal improvement.
- A track record reflecting experimental rigor, creativity, and productivity in protein sciences and structural biology.
- Ability to thrive in a fast‑paced, highly collaborative, and multi‑project research environment.
- Excellent communication and interpersonal skills, with commitment to collaborative science, knowledge sharing, and inclusive teamwork.
Preferred Qualifications
- Experience working with various protein classes and multi-protein complexes, including strategies to stabilize and optimize samples for downstream structural, biochemical and biophysical analysis
- Hands‑on experience with protein purification and crystallization instrumentation, including chromatography systems, crystallization platforms, and automated crystal imaging and screening technologies.
- Experience with cryo‑electron microscopy workflows including sample optimization and grid preparation
- Experience applying ML/AI‑enabled approaches to protein engineering, construct design, or structure determination.
PHYSICAL/MENTAL REQUIREMENTS
Must be able to work safely in a laboratory environment with lab coat, protective eye wear and gloves. The job requires standing, walking for most of the day regular workday with occasional lifting of moderately heavy lab utilities. Candidate may need to use step stools to climb and reach items above eye level. Candidate will also diagnose and repair equipment with various tools occasionally.
Work Location Assignment: On Premise
Relocation assistance may be available based on business needs and/or eligibility.

Candidates must be authorized to be employed in the U.S. by any employer.
U.S. work visa sponsorship (such as TN, O-1, H-1B, etc.) is not available for this role now or in the future.

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