Eman AhmedRutgers BME

Research area

Keeping enzymes working outside water

Doctoral work on random copolymers as synthetic chaperones for enzymes in water-miscible organic solvents, screened on an automated plate-based platform.

Enzymes are extraordinary catalysts in water and frequently useless outside it. Move one into a water-miscible organic solvent, often where the interesting synthetic chemistry happens, and it tends to unfold, aggregate and drop out of solution.

Random copolymers can act as synthetic chaperones, wrapping a protein in a shell whose chemistry is tunable monomer by monomer. The difficulty is that the relationship between that shell's composition and whether the enzyme survives is not obvious from first principles.

The space is too big to reason about

Why this has to be run in parallel

A deliberately conservative design space: six monomers, three per polymer, composition in 10% steps, four chain lengths, and it is already past what anyone screens by hand.

2,880 polymers is about 30 plates. At one hand-run reaction per hour it is years of benchwork; on an automated platform it is a manageable campaign. And the real space is larger, because composition does not come in tidy 10% steps.

Show the numbers
QuantityValueHow
Monomers available6an illustrative palette
Monomers per copolymer3terpolymers
Distinct monomer sets20C(6,3)
Compositions per set3610% increments summing to 100%
Chain-length targets4degree of polymerisation
Total distinct polymers2,88020 × 36 × 4
Plates required30at 96 formulations per plate

Computed Plain combinatorial arithmetic for an illustrative palette, not a description of a specific screen. The point is the order of magnitude.

How the screen runs

The assay, end to end

Each step has to survive being done ninety-six times in parallel without the numbers drifting.

Six steps: synthesise copolymer library, add enzyme, transfer to organic solvent, read solubility, read retained activity, model structure-function.1Synthesisecopolymerphoto-ATRP, one plate2Add enzymeform polymer–enzyme hybrid3Transfer toorganicwater-miscible4Readsolubilityplate reader5Read retainedactivityenzyme assay6Modelstructure–functionon every well, including failures
Show the numbers
StepStageDetail
1Synthesise copolymer libraryphoto-ATRP, one plate
2Add enzymeform polymer–enzyme hybrid
3Transfer to organic solventwater-miscible
4Read solubilityplate reader
5Read retained activityenzyme assay
6Model structure–functionon every well, including failures

Schematic A diagram of the approach. Results from this work are in preparation and are not shown here.

Two things make this work as a dataset rather than a set of experiments. Every well is measured the same way, and the wells that fail are kept. A polymer that leaves the enzyme insoluble produces a number, and that number is as informative for modelling as a success.

This work is in preparation. No results are shown on this page, and the figures above describe the approach rather than reporting outcomes.

Status

This is ongoing doctoral work and the manuscript is in preparation. If you are working on something adjacent, I would rather talk before it is published than after.

Other research areas