*We have put a quantum computer to use and managed to stay well within the limit of chemical accuracy. This means a significant step towards increasing our understanding of how enzymes work at the atomic level, bringing us much closer to e.g. industrial carbon-capture.*

As the first company in the world, we have simulated the first enzymatic reaction using a quantum computer.

And not only that, we have done it well within the limit of chemical accuracy, which is defined as 1 kcal/mol. This quantity is crucial as it represents the error requirement for modelling chemical reaction in a **quantitative** manner.

Besides the fact that nobody has made calculations on an enzymatic reaction on a quantum computer before, it’s huge because calculations of this kind can help speed up the process in drug discovery and other industrial processes where enzymes play a key role.

Furthermore, it shows that quantum computing isn’t just a thing for the future. It’s already a powerful tool when put into the hands of experts.

In this work, we have applied our own FAST-VQE algorithm in a quantum/classical hybrid computational approach and simulated the proton-transfer step for CO_{2} hydration catalysed by carbonic anhydrase.

The graph shows how we can bring quantum computing solutions very close to classical computing ones. In particular, the deviation is within chemical accuracy, defined as 1 kcal/mol. This quantity is crucial as it represents the error requirement for modelling chemical reactions in a **quantitative** manner.

**Releasing the potential of nature**

Enzymes play a key role in a vast number of crucial, chemical reactions and they can be found almost everywhere in Nature. Most of them are the result of thousands of years of natural evolutions, some others are made in laboratories to fulfil specific requirements. For this project, Kvantify and Novonesis decided on one of nature’s own enzymes, carbonic anhydrase.

So our accomplishment isn’t just good for advancing quantum computing technology - it has the potential to play a role in fighting climate change as well.

This enzyme catalyzes the conversion of CO_{2 }and water into carbonic acid, a crucial process for many organisms, among other things, regulating blood pH and transporting carbon dioxide in the body, and – given the right circumstances – has the potential for industrial carbon capture.

**Our new approach**

The complexity of a quantum mechanical problem grows exponentially with the number of atoms involved. So, when dealing with enzymes, we must be on our toes, as they are large molecular systems which can be composed of hundreds or thousands of atoms in some cases.

Simply put, we use a quantum computer for quantum calculations and classical high-performance computing (HPC) for the “molecular mechanics” calculations. The quantum computer gives accuracy, while HPC brings speed.

For the quantum mechanical part, we designed a new algorithm, called FAST-VQE, that outperforms the ones commonly used by others in our field.

The reaction energy profile obtained from the FAST-VQE exhibits a low deviation from the classical computing results, typically taken as benchmark. This highlights the solid performances of the FAST-VQE algorithm and stresses how we have narrowed the gap between classical and quantum computing considerably.

One problem for many has not only been to do the actual calculations on a quantum computer, but also to get results that are within the area of chemical accuracy, which is defined as 1 kcal/mol. This quantity is crucial as it represents the error requirement for modelling chemical reaction in a quantitative manner.

As mentioned above, we have done both as the graph shows. This means that we have brought quantum computing solutions very close to classical computing ones.

The progress made to date indicates the growing maturity and enormous potential of quantum computing technology and the possible modelling of enzymatic reactions, as reported for the first time by us, represents vivid evidence of this.

If you want to learn more about how we found the right mix of quantum and molecular mechanics, **drop us an email**, and we will send you some of our more technical considerations on this matter.

*On behalf of the team at Kvantify*