Principal Scientist, Process Development (Expression Systems)

The Role

Moderna is seeking an Individual to lead host strain, vector, and expression system strategy for E. coli-based production of recombinant enzymes, plasmids, and related biological materials supporting Moderna’s technology platforms and pipeline programs.

This role owns the front end of microbial production: designing, building, screening, and selecting host/vector/expression systems that enable high-performing, scalable, and robust upstream processes.

The successful candidate will bring deep expertise in microbial genetics, molecular biology, expression-system design, screening workflows, data-driven construct selection, and translation of small-scale screening outputs into process-development-ready leads.

Here’s What You’ll Do

• Own the strategy for E. coli host strain, vector, and expression-system for recombinant enzymes, plasmids, and related biological materials.
• Design and execute screening cascades that identify production candidates with strong titer, yield, quality, genetic stability, robustness, and process-development potential.
• Define stage-appropriate decision criteria for host/vector selection, expression tuning, induction strategy, plasmid stability, growth, product quality, and manufacturability.
• Develop and optimize small-scale and high-throughput screening workflows, including shake flask, deep-well plate, ambr, or other scale-down systems where appropriate.
• Evaluate host strains, promoters, ribosome binding sites, copy number, plasmid architecture, induction systems, codon/design strategies, secretion or localization strategies where relevant, and expression timing.
• Use DOE and data-driven approaches to improve screening throughput, predictiveness, reproducibility, and translation to bioreactor performance.
• Lead or support strain and vector engineering to improve expression performance, stability, productivity, robustness, and manufacturability.
• Apply molecular biology, microbial physiology, and synthetic biology principles to troubleshoot poor expression, instability, toxicity, metabolic burden, inclusion body formation, degradation, or inconsistent performance.
• Define fit-for-purpose characterization and handoff packages for candidate strains and constructs, including strain/vector history, design rationale, screening data, stability observations, known risks, and recommended development paths.
• Partner with process development, analytical development, downstream purification, informatics, automation, and data science teams to ensure screening outputs are actionable and linked to relevant quality and process attributes.
• Develop platform approaches and standardized documentation, data capture, decision criteria, and knowledge-management practices for recurring enzyme, plasmid, or microbial production needs.
• Support cross-functional troubleshooting, technical reports, development summaries, CMC-supporting documentation, and regulatory responses as needed.
• Serve as a technical leader and mentor in microbial genetics, molecular biology, expression-system design, screening strategy, and data interpretation.

Here’s What You’ll Need (Basic Qualifications)

• PhD in Molecular Biology, Microbiology, Chemical/Biochemical Engineering, Biotechnology, Synthetic Biology, or a related discipline with 5+ years of relevant industry experience; or MS with 10+ years; or BS with 12+ years of relevant industry experience.
• Substantial industry experience with E. coli strain engineering, vector design, expression-system development, or microbial production screening.
• Hands-on expertise developing and executing microbial expression-screening workflows for recombinant proteins, enzymes, plasmids, or related biological products.
• Strong understanding of E. coli genetics, physiology, metabolism, plasmid biology, expression regulation, and genetic stability.
• Experience designing and interpreting experiments that connect host/vector/expression choices to titer, yield, quality, robustness, and manufacturability.
• Experience with small-scale or high-throughput screening systems and translation of screening data into process-development decisions.
• Demonstrated ability to lead complex technical projects, influence stakeholders across functions, and communicate clearly through technical writing, data analysis, and presentations.

Here’s What You’ll Bring to the Table (Preferred Qualifications)

• Direct experience developing E. coli expression systems for recombinant enzymes and/or plasmid production.
• Experience with strain engineering, promoter/RBS libraries, plasmid copy-number optimization, induction-system tuning, codon/design strategies, secretion/localization approaches, or protein solubility optimization.
• Experience building screening cascades that balance speed, throughput, biological relevance, and scale translation.
• Working knowledge of fermentation process development, downstream interfaces, and analytical methods used to assess expression, identity, purity, activity, plasmid quality, host-cell impurities, nucleic acid burden, or product-related impurities.
• Experience supporting CMC-facing documentation, technical reports, regulatory questions, and operation as either a senior technical individual contributor or manager of a small technical team.

Pay & Benefits

At Moderna, we believe that when you feel your best, you can do your best work.  That’s why our US benefits and global well-being resources are designed to support you—at work, at home, and everywhere in between.

• Best-in-class healthcare coverage, plus voluntary benefit programs to support your unique needs

• A holistic approach to well-being, with access to fitness, mindfulness, and mental health support

• Family planning benefits, including fertility, adoption, and surrogacy support

• Generous paid time off, including vacation, volunteer days, sabbatical, global recharge days, and a discretionary year-end shutdown

• Savings and investment opportunities to help you plan for the future

• Location-specific perks and extras

The salary range for this role is $142,500.00 - $256,500.00. This is the lowest to highest salary we in good faith believe we would pay for this role at the time of this posting. An individual’s position within the salary range will be based on several factors including, but not limited to, specific competencies, relevant education, qualifications, certifications, experience, skills, performance, and business or organizational needs.

The successful candidate may be eligible for an annual discretionary bonus, other incentive compensation, or equity award, subject to company plan eligibility criteria and individual performance.

About Moderna

Since our founding in 2010, we have aspired to build the leading mRNA technology platform, the infrastructure to reimagine how medicines are created and delivered, and a world-class team. We believe in giving our people a platform to change medicine and an opportunity to change the world.  

By living our mission, values, and mindsets every day, our people are the driving force behind our scientific progress and our culture. Together, we are creating a culture of belonging and building an organization that cares deeply for our patients, our employees, the environment, and our communities. 

We are proud to have been recognized as a Science Magazine Top Biopharma Employer, a Fast Company Best Workplace for Innovators, and a Great Place to Work in the U.S. 

If you want to make a difference and join a team that is changing the future of medicine, we invite you to visit modernatx.com/careers to learn more about our current opportunities. 

Our Working Model 

As we build our company, we have always believed an in-person culture is critical to our success. Moderna champions the significant benefits of in-office collaboration by embracing a 70/30 work model. This 70% in-office structure helps to foster a culture rich in innovation, teamwork, and direct mentorship. Join us in shaping a world where every interaction is an opportunity to learn, contribute, and make a meaningful impact. 

Moderna is a smoke-free, alcohol-free, and drug-free work environment. 

Equal Opportunities

Moderna is committed to equal employment opportunity and non-discrimination for all employees and qualified applicants without regard to a person's race, color, sex, gender identity or expression, age, religion, national origin, ancestry or citizenship, ethnicity, disability, military or protected veteran status, genetic information, sexual orientation, marital or familial status, or any other personal characteristic protected under applicable law.  Moderna is a place where everyone can grow. If you meet the Basic Qualifications for the role and you would be excited to contribute to our mission every day, please apply!

Moderna is an E-Verify Employer in the United States. We consider qualified applicants regardless of criminal histories, consistent with legal requirements. 

Accommodations

We’re focused on attracting, retaining, developing, and advancing our employees. By cultivating a workplace that values diverse experiences, backgrounds, and ideas, we create an environment where every employee can contribute their best. 

Moderna is committed to offering reasonable accommodations to qualified job applicants with disabilities. Any applicant requiring an accommodation in connection with the hiring process and/or to perform the essential functions of the position for which the applicant has applied should contact the Accommodations team at leavesandaccommodations@modernatx.com. 

Export Control Notice
This position may involve access to technology or data that is subject to U.S. export control laws, including the Export Administration Regulations (EAR). As such, employment is contingent upon the applicant’s ability to access export-controlled information in accordance with U.S. law. Due to the nature of the work and regulatory requirements, only individuals who qualify as U.S. persons (citizens, permanent residents, asylees, or refugees) are eligible for this position. For this role Moderna is unable to sponsor non-U.S. persons to apply for an export control license.
#LI-TR2

-