Dr Florian Hollfelder’s group operates at the intersection of Chemical Biology and Droplet Microfluidics, seeking a fundamental understanding of molecular recognition processes in enzymes and proteins. The research is driven by questions surrounding how protein evolution works, the chemical and biophysical basis of catalysis, and how extreme miniaturization techniques can solve chemical and biological problems. This work extends the mechanistic lessons of enzyme evolution and droplet microfluidics to practical applications in synthetic chemistry, medicine, and biotechnology, notably in repurposing existing enzymes like sulfatases and exploring the limits of specificity and promiscuity in enzyme superfamilies.
Dr Florian Hollfelder: Group Leader | Enzyme Evolution and Droplet Microfluidics
Introduction and Research Niche
Dr. Florian Hollfelder leads a highly interdisciplinary research group focused on Chemical Biology: from mechanism to droplet microfluidics (and back). The central mission is to unlock the fundamental principles that govern molecular recognition processes and biological catalysis—the machinery that makes life’s chemistry run smoothly and efficiently.
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Nature has optimized enzymes into the most powerful catalysts known. The Hollfelder Group uses an eclectic mix of techniques, blending rigorous chemical and biophysical analysis with advanced engineering, to understand how functional molecules are made and how they evolve. The ultimate goal is to apply these mechanistic lessons to biotechnology, synthetic chemistry, and medicine, bridging the gap between fundamental molecular science and real-world applications.
Graduate Research Opportunities
The Hollfelder Group offers doctoral candidates projects that cross traditional boundaries, providing expertise in protein engineering, quantitative analysis, and microfluidic technology. Research is organized around these three core and highly collaborative streams:
1. Research Stream: Principles of Enzyme Evolution and Function
This stream addresses the most profound question in molecular biology: How do functional proteins arise? We investigate the biophysical and chemical factors that define enzyme behavior, specifically looking at how specificity and catalytic promiscuity are balanced in evolving systems.
- Topics: Studying multidimensional activity transitions within large enzyme superfamilies, such as the alkaline phosphatase superfamily, to map evolutionary landscapes. Investigating the evolutionary repurposing of enzymes (e.g., sulfatases) to understand how small changes in the Michaelis complex lead to dramatic shifts in catalytic efficiency and transition state stabilization.
2. Research Stream: Biological Catalysis and Molecular Recognition
This focus area is dedicated to providing rigorous chemical and biophysical explanations for biological catalysis. The work involves detailed mechanistic studies to describe, manipulate, and ultimately engineer functional molecules and protein binders.
- Topics: Quantitative analysis of binding affinities, kinetic mechanisms, and transition state analysis using techniques like steady-state and pre-steady-state kinetics, to put our understanding of enzyme function on a firm, predictive footing.
3. Interdisciplinary Focus: Droplet Microfluidics and Ultrahigh-Throughput Screening (UHTS)
This is the technology stream, which exploits the power of extreme miniaturization to achieve breakthroughs in enzyme evolution and droplet microfluidics. Encapsulating reactions in picoliter droplets drastically accelerates the pace of discovery.
- Topics: Developing and applying novel microfluidic methods, including Absorbance-Activated Droplet Sorting (AADS), for ultrahigh-throughput-directed enzyme evolution. Projects include the discovery of promiscuous enzymes from metagenomic libraries by confining thousands of reactions per second into tiny, biomimetic gel-shell beads or droplets.
Key Awards and Professional Roles
| Detail | Role / Status | Institution / Body |
|---|---|---|
| Core Discipline | Chemical Biology and Biophysics | University of Cambridge |
| Research Focus | Protein Evolution and Directed Evolution | Synthetic and Mechanistic Biology |
| Key Technology | Droplet Microfluidics and UHTS | Biotechnology and Bioengineering |
| Previous Affiliations | High-impact research in Europe | Academic and Research Institutions |
Selected Publications
Journal Article (2019): “Balancing specificity and promiscuity in enzyme evolution: Multidimensional activity transitions in the alkaline phosphatase superfamily.” J. Am. Chem. Soc.
Journal Article (2018): “Evolutionary repurposing of a sulfatase: A new Michaelis complex leads to efficient transition state charge offset.” Proc. Natl. Acad. Sci. U.S.A.
Journal Article (2016): “Ultrahigh-throughput-directed enzyme evolution by absorbance-activated droplet sorting (AADS).” Proc. Natl. Acad. Sci. U.S.A.
Journal Article (2015): “Ultrahigh-throughput discovery of promiscuous enzymes by picodroplet functional metagenomics.” Nat. Commun.
Journal Article (2014): “Evolution of enzyme catalysts caged in biomimetic gel-shell beads.” Nat. Chem.
Contact Information
Prospective students interested in supervision should reach out via the following channels:
| Detail | Content |
|---|---|
| Email Address
|
fh111@cam.ac.uk |
| University Profile Page | Link to official University faculty page |
Supervisory Ethos
Dr. Hollfelder believes in fostering an environment of intellectual curiosity, scientific rigor, and open collaboration. The lab is a melting pot of diverse skills, welcoming students from backgrounds in Chemistry, Biochemistry, Physics, and Engineering. Mentorship is hands-on and tailored, encouraging students to become highly independent researchers capable of bridging complex theoretical concepts with innovative experimental design. He seeks candidates who are motivated by fundamental scientific questions and are excited by the prospect of developing and applying new technologies to understand how life works at the molecular level. The goal is to train the next generation of leaders in enzyme evolution and droplet microfluidics prepared for careers in both academia and industry.
Frequently Asked Questions (FAQ)
1. What is the difference between chemical biology and biochemistry in your lab?
While we use biochemical tools, our work is driven by chemical biology—we use chemical principles and techniques (like microfluidics and synthetic substrates) to understand, manipulate, and create biological systems, moving beyond descriptive biology to engineering and design.
2. What are “picoliter droplets” and why are they important?
Picoliter droplets are tiny (one trillionth of a liter) aqueous compartments generated using microfluidic devices. They act as individual, miniaturized test tubes, allowing us to screen millions of enzymes or cells per day, which is essential for ultrahigh-throughput-directed enzyme evolution.
3. What is Absorbance-Activated Droplet Sorting (AADS)?
AADS is a technology developed in our lab that allows us to rapidly identify and sort droplets based on a color change (absorbance) inside the picoliter volume. This is how we select the best-performing enzymes from massive screening libraries.
4. Is prior experience with microfluidics required for a PhD?
No, prior experience is not required. We train students from scratch. We welcome candidates with a strong foundation in chemistry or biochemistry who are keen to learn new engineering and biophysical techniques.
5. How does your research on enzyme evolution contribute to biotechnology?
By understanding the principles of enzyme evolution, we can direct the process to create novel biocatalysts for green chemistry (replacing harsh chemical reagents) or engineer proteins with new binding properties for diagnostic and therapeutic applications.
6. What kind of computational work is involved in the group?
We often collaborate on computational chemistry and molecular dynamics simulations (as seen in our PNAS paper on evolutionary repurposing) to support and rationalize our experimental findings regarding transition states and reaction mechanisms.
7. What pathogens, if any, do you work with?
We do not typically work with pathogens. Our focus is on the fundamental mechanisms of enzyme catalysis and developing technologies like droplet microfluidics for general molecular discovery, which can then be applied broadly across biology.
8. What does “molecular recognition” mean in the context of your research?
Molecular recognition is the specific non-covalent interaction between two or more molecules, such as an enzyme binding its substrate, or an antibody binding an antigen. We investigate the chemical and physical rules that govern the strength and specificity of these interactions.
9. Is this project more Chemistry or Biology focused?
It is genuinely balanced. Students gain deep expertise in Biochemistry (mechanism and evolution) and Physical Chemistry (kinetics and technology development). The research sits squarely in the interdisciplinary field of Chemical Biology.
10. What kind of publication record can I expect from the group?
The group has a high-impact publication record, consistently publishing in top-tier journals like Nature Chemistry, PNAS, and the Journal of the American Chemical Society (JACS), reflecting the originality and rigor of the enzyme evolution and droplet microfluidics work.
