Hydrogen oxidizing bacteria engineered to valorize CO2 for whey protein production

Introduction

Milk protein plays an important role in our nutrition; however, classical milk production has significant environmental impacts, from greenhouse gas (GHG) emissions to extensive land demand. Project HYDROCOW addresses these challenges through a net-zero carbon dairy protein production platform.

Project Objectives

The main objective of the project is to develop and demonstrate a bacterial protein secretion system where CO2 and soon N2 are valorized into food-grade protein, decoupled from agriculture. This system will be based on the first-of-a-kind engineered hydrogen oxidizing bacterium (eHOB) Xanthobacter sp. SoF1. As a first product, the main milk component beta-lactoglobulin was chosen.

Technical Approach

Technically, this will be achieved by implementing a Design-Build-Test-Learn (DBTL) cycle linked to a validation and scale-up phase, allowing for iterative optimization of the production of secreted protein. The project will deliver key technologies:

1. An innovative eHOB protein secretion system.
2. Predictive eHOB metabolic models, genetic engineering tools, and a novel high-throughput (HTP) screening system for DBTL cycling.
3. Methods for validation and scale-up with immediate and long-term impact on the production of food and nutrition, materials, medicines, fuels, and chemicals.

Long-term Impact

In the long term, the proposed platform has the potential to not only replace conventionally produced food proteins but also deliver proteins for materials or therapeutics, which are important for human and animal health.

Sustainability Considerations

In comparison to current standard microbial production processes, our platform does not compete with human nutrition for valuable feedstock, such as glucose, and therefore will contribute to the sustainable development of our society.

Knowledge Generation

HYDROCOW will generate significant knowledge for a growing research and application community about autotrophic microbial production systems, their physiology, and sophisticated tools for genetically designing and screening them.