What are the responsibilities and job description for the Senior Research Associate – Protein Expression & Process Development position at Kisoji Biotechnology Inc.?
KisoJi Biotech is advancing next-generation antibody therapeutics through the integration of proprietary transgenic heavy chain-only antibody (HCAb) platforms, AI-guided discovery, and high-throughput protein production systems.
We are currently expanding our protein sciences capabilities and are seeking two Senior Research Associates to lead and support our recombinant protein expression and purification workflows across multiple expression systems including mammalian (HEK293, CHO/ExpiCHO), insect (Sf9/Hi5), and bacterial (E. coli) hosts.
This is a highly hands-on laboratory role focused on developing, optimizing, and scaling protein expression and downstream purification processes to support antibody discovery, functional screening, and structural biology programs. The position will involve close collaboration with multidisciplinary teams spanning molecular biology, antibody engineering, AI-guided discovery, and analytical characterization.
The successful candidates will thrive in a fast-paced biotech environment, demonstrate strong experimental rigor, work independently, and contribute scientifically to the development of robust, high-yield protein production pipelines for next-generation antibody therapeutics.
Position: Senior Research Associate
Site: San Diego, California, USA
Department: Process Development
Qualifications & Responsibilities
Education & Experience
- MSc. or Ph.D. in Molecular Biology, Biochemistry, or a related field with a minimum of 2 years of hands-on industry or research experience
- Demonstrated track record of independent project ownership in a fast-paced biotech or research environment
Core Technical Responsibilities
- Lead and optimize recombinant protein expression across mammalian (HEK293, CHO/ExpiCHO), insect (Sf9/Hi5), and bacterial (E. coli) expression systems
- Drive cell line development workflows to establish stable, high-yield antibody-producing cell lines
- Execute and optimize downstream purification of recombinant antibodies and proteins using FPLC-based chromatography systems (affinity, ion exchange, size exclusion)
- Develop and troubleshoot expression and purification strategies for challenging targets, including membrane proteins, ensuring high purity and yield
- Maintain and apply biophysical characterization methods to assess protein quality, homogeneity, and functionality
- Desirable (not mandatory): Experience with membrane protein reconstitution into nanodiscs or other lipid-based systems for structural or functional studies
Collaboration & Leadership
- Partner closely with molecular biology, antibody discovery, and assay development teams to align protein production timelines with program milestones
- Contribute to experimental design, data interpretation, and scientific reporting
Professional Competencies
- Strong problem-solving ability with a systematic approach to diagnosing and resolving expression and production challenges
- Excellent written and oral communication skills for internal reporting and cross-functional collaboration
- Highly motivated, detail-oriented, and capable of managing multiple projects simultaneously while meeting deadlines
- Flexible and adaptable to evolving priorities in a dynamic biotech environment, with the ability to work both independently and as part of a team
What We Offer
Benefits
- Comprehensive health and dental insurance plans
- Paid vacation and statutory holidays
Growth & Development
- Structured training and professional development programs
- Annual performance reviews with merit-based bonuses
- Opportunity to work with cutting-edge, proprietary antibody discovery technologies
- Direct exposure to advanced AI-guided therapeutic discovery platforms
Compensation
The salary range for this position is $100,000–$120,000 USD annually, commensurate with experience, technical expertise, and qualifications. Final compensation will reflect internal equity, relevant industry experience, and candidate qualifications.
How to Apply
Interested candidates are invited to submit a cover letter outlining their fit for this position, along with a current CV, to: contact@kbimail.com
Please include the position title, department, and site location in the subject line of your email. Applications submitted through any other channel will not be considered. Shortlisted candidates will be asked to provide professional references and a detailed skills inventory.
We thank all applicants for their interest; only those selected for an interview will be contacted.
Salary : $100,000 - $120,000