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Principal Associate Scientist

Brisbane, California, United States

About Xaira Therapeutics

Xaira is an innovative biotech startup focused on leveraging AI to transform drug discovery and development. The company is leading the development of generative AI models to design protein and antibody therapeutics, enabling the creation of medicines against historically hard-to-drug molecular targets. It is also developing foundation models for biology and disease to enable better target elucidation and patient stratification. Collectively, these technologies aim to continually enable the identification of novel therapies and to improve success in drug development. Xaira is headquartered in the San Francisco Bay Area, Seattle, and London.

About the Role
As a part of the Protein Biochemistry team, you will play a crucial role in discovering and developing novel biotherapeutics. The ideal candidate will have demonstrable experience in the expression, purification, and characterization of monoclonal and bi/multispecific antibodies within a biotherapeutics discovery setting, coupled with a proactive and can-do attitude.

Responsibilities:

  • Support the discovery and development of therapeutic molecules through hands-on laboratory work.
  • Design constructs for the expression of antibodies and other proteins.
  • Express antibodies and other proteins using transient transfection in mammalian expression systems at milliliter to liter scales.
  • Purify proteins using a variety of chromatographic techniques, including affinity, size exclusion, and ion exchange chromatography.
  • Perform antibody characterization assays using biophysical and biochemical methods, including affinity measurements (BLI, SPR), ELISA, MSD, and flow cytometry.
  • Store antibodies and proteins in dedicated databases and maintain detailed records.
  • Support other workflows as needed, including cell culture maintenance, binder discovery assays, functional assays, and developability analysis.
  • Analyze experimental data, generate reports, and present findings to the team and cross-functional teams.
  • Build and maintain an updated understanding of program needs.
  • Maintain accurate and up-to-date experiment records in an ELN.
  • Ensure compliance with laboratory safety protocols and contribute to lab organization and operations.

Qualifications:

  • BA or MS degree in molecular biology, structural biology, biophysics, biochemistry, or a related discipline, with 4+ years of industry experience.
  • Experience in molecular biology and vector design for protein expression.
  • Extensive hands-on experience with mammalian cell expression systems.
  • Deep experience in protein and antibody (including monoclonals, bispecifics, and antibody fragments) purification and characterization techniques (including affinity, ion exchange, HIC, SEC) and in chromatography hardware and software (including Cytiva AKTA, Agilent HPLC).
  • Experience in developing and optimizing protein purification methods.
  • Experience in antibody characterization using biosensors (BLI, SPR), ELISA, MSD, and flow cytometry.
  • Proficiency in data analysis software (e.g., GraphPad Prism) and statistical tools.
  • Proactive attitude with a self-starter mindset.
  • Strong organizational, communication, and interpersonal skills.
  • Strong collaborative skills and interest in working in cross-functional teams and a startup environment.
  • Excellent problem-solving and troubleshooting abilities.
  • Ability to work independently with accountability and meticulous attention to detail.

Compensation: Annual

We offer a competitive compensation and benefits package, seeking to provide an open, flexible, and friendly work environment to empower employees and provide them with a platform to develop their long-term careers. A Summary of Benefits is available for all applicants. We offer a competitive package that includes base salary, bonus, and equity.  The base pay range for this position is expected to be $110,000 - $138,000 annually; however, the base pay offered may vary depending on the market, job-related knowledge, skills and capabilities, and experience.

Xaira Therapeutics an equal-opportunity employer. We believe that our strength is in our differences. Our goal to build a diverse and inclusive team began on day one, and it will never end.

TO ALL RECRUITMENT AGENCIES: Xaira Therapeutics does not accept agency resumes. Please do not forward resumes to our jobs alias or employees. Xaira Therapeutics is not responsible for any fees related to unsolicited resumes.

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