Ideation

Our journey began with a broad interest in Vitamin B12 absorption and the health challenges surrounding its deficiency. Early discussions of our team revolved around a deceptively simple question: “Can we design a better way to deliver B12 to people who cannot absorb it efficiently?” Meanwhile, we learned that while dietary B12 deficiency is common among certain populations, a significant number of patients suffer from malabsorption due to problems with intrinsic factor (IF), which is a glycoprotein essential for B12 uptake in the small intestine [1].

Step 1: Identifying the Problem

Step 2: Exploring Possible Approaches

Step 3: Deep Dive into Background Research

Step 4: Refining the Concept

Click to read more on how our literature review shaped the IF species selection:

Engineering target

Our goal is to engineer and compare intrinsic factor (IF) proteins from a range of species to discover variants that bind vitamin B12 more effectively, interact optimally with human receptors, and are less affected by autoimmune antibodies. By identifying the most resilient and efficient IF candidates, we aim to lay the groundwork for next-generation oral B12 supplements that can overcome absorption deficiencies, reduce reliance on injections, and offer a scalable, sustainable alternative for at-risk populations.

DBTL cycle (IF)

At the start of our cross-species intrinsic factor project, we recognized the importance of approaching the work as an engineering challenge. Our aim was not only to express intrinsic factor Komagataella phaffii (pichia pastoris), but to produce variants from multiple species and systemically compare their structural and functional properties. To achieve this, we adopted the Design-Build-Test-Learn (DBTL) cycle widely used in synthetic biology, tailoring it to the practical realities of our workflow. In the design phase, we planned the genetic constructs and identified the analytical methods most suitable for our objectives and resources. The build phase involved cloning and expression, followed by verification of construct integrity and protein production. At each test stage, we conducted feasible assays to assess expression levels, folding, and binding characteristics. The outcomes informed the learn phase, allowing us to refine experimental conditions, troubleshoot issues, and prioritise subsequent steps.

Figure 1. Design-Built-Test-Learn cycle of cross-species engineering of IF in Komagataella phaffii (pichia pastoris)

Figure 2. Overview of our project’s wet-lab workflow, illustrating the iterative design-build-test-learn (DBTL) cycle stages

Design

Build

Test

Learn

References

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