Senior Scientist, E. coli Expression Systems

RXinsider LTD.; Norwood (MA); On-site; USD 142,500 - 256,500; Full time

Benefits offered by this job

Healthcare coverage

Well-being resources

Paid time off

Discretionary bonus eligibility

Job summary

Moderna seeks a Principal Scientist to lead host strain, vector, and expression-system strategies for E. coli-based production of enzymes and plasmids.

This role drives screening programs to identify robust, scalable candidates and translates screening data into process-development-ready leads. You will mentor colleagues in microbial genetics and expression-system design, collaborate with cross-functional teams, and shape platform approaches for recurring enzymatic needs across Moderna’s

Qualifications

• PhD in Molecular Biology, Microbiology, Biotechnology, Synthetic Biology, or related field with 5+ years industry experience (or MS with 10+ years; or BS with 12+ years).
• Substantial industry experience with E. coli strain engineering, vector design, expression-system development, or microbial production screening.
• Hands-on expertise developing microbial expression-screening workflows for recombinant proteins, enzymes, plasmids, or related products.
• Strong understanding of E. coli genetics, physiology, metabolism, plasmid biology, expression regulation, and genetic stability.
• Experience designing and interpreting experiments linking host/vector/expression choices to titer, yield, quality, robustness, and manufacturability.
• Experience with small-scale or high-throughput screening systems and translating screening data to process decisions.
• Demonstrated ability to lead complex technical projects and communicate clearly across functions.

Responsibilities

• Own the strategy for E. coli host strain, vector, and expression-system for enzymes and plasmids.
• Design and execute screening cascades identifying production candidates with strong titer, yield, quality, and robustness.
• Define stage-appropriate criteria for host/vector selection and induction strategies.
• Develop and optimize small-scale and high-throughput screening workflows (shake flask, ambr, etc.).
• Evaluate host strains, promoters, RBS, copy number, and plasmid architecture.
• Apply DOE and data-driven approaches to improve screening throughput and translation to bioreactor performance.
• Lead strain and vector engineering to improve expression and manufacturability.
• Troubleshoot expression-related issues using molecular biology and microbial physiology principles.
• Define characterization packages for candidate strains and constructs for handoff.

Skills

E. coli strain engineering

Expression-system design

High-throughput screening

Data-driven construct selection

Project leadership

Technical writing & presentations

Education

PhD in Molecular Biology, Microbiology, or related

MS with 10+ years of industry experience

Tools

Shake flask screening

Ambr systems

High-throughput screening hardware

Job description

Moderna seeks a Principal Scientist to lead host strain, vector, and expression-system strategies for E. coli-based production of enzymes and plasmids.

This role drives screening programs to identify robust, scalable candidates and translates screening data into process-development-ready leads. You will mentor colleagues in microbial genetics and expression-system design, collaborate with cross-functional teams, and shape platform approaches for recurring enzymatic needs across Moderna’s