EASTBIO Developing sustainable, synthetic cascades with man-made and natural biocatalysts

The application of biocatalysts for the synthesis of both high value and commodity chemicals continues to grow with leading academic labs discovering new biocatalysts that can catalyse novel chemical reactions (Herrera & Campopiano, Nature Synthesis, 2022). At the same time, industrial experts such as Merck and Codexis are combining their skills in screening and directed evolution of biocatalysts to generate complex, multi-step cascades able to convert simple building blocks into target molecules in high % yield (Fryszkowska & Devine – Curr. Op. in Chem. Biol., 2020). This “Green Revolution” promises to generate molecules in a sustainable way with renewable feedstocks.

Consecutive modifications of simple functional groups can generate a complex organic molecule with many chiral centres. Recent examples include the production of an anti-diabetic drug Sitagliptin using a single engineered transaminase (TA) and a nine-biocatalyst cascade for the production of an anti-HIV drug, Islatravir. As well as adapting natural enzymes for biocatalytic applications, experts have also developed biocatalysts for reactions not previously known to be catalysed by enzymes. One example is the Morita-Baylis-Hillman (MBH) reaction (Crawshaw et al., Nature Chemistry, 2022). This well-known, versatile reaction makes new C-C bonds between activated alkenes with aldehydes to form target molecules which are suitable chiral building blocks. The new MBH biocatalyst (BH32.14) was arrived at by directed evolution and selection from a core protein scaffold that turns over one molecule per day. Successive rounds of selection led to the isolation of BH32.14 from a dense library of variants – the MBH biocatalyst contained key His/Arg catalytic residues whose role in catalysis was revealed through x-ray crystallography. The BH32.14 biocatalyst could function at >100mg scale with low % catalyst loading and mM substrate concentrations.

Now, in this novel EastBio project we will combine this “man-made” MBH biocatalyst with a range of “natural” isolates namely; TAs, ketoreductases (KRs), ene-reductases (ERs) and acetylases. This combination of cascade reactions will generate a large library of organic products with dense, 3D functionality. Such molecules will find use in the biotechnology and pharma industries. As well as purified biocatalysts, we also aim to construct these synthetic pathways in engineered bacterial strains. This project will train a PhD student in modern methods of enzyme engineering, directed evolution, enzyme assay, microbiology, chemical analysis and route optimisation.

Application Process:

To apply for an EASTBIO PhD studentship, follow the instructions below:

 ·        Informal enquiries should be addressed to Professor Campopiano. To apply, please send a cover letter outlining your previous research experience and reasons for applying, alongside an up-to-date CV to [Email Address Removed]

 ·        After you have discussed the projects of interest to you with Professor Campopiano, download and complete our Equality, Diversity and Inclusion survey and then fill in the EASTBIO Application Form and submit this to Professor Campopiano.

 ·        Send the EASTBIO Reference Form to your two academic/professional referees, and ask them to submit your references directly to Prof. Dominic Campopiano [Email Address Removed]

 We anticipate that our first set of interviews will be held 6^th – 10^th February 2023.

 If you have further queries about the application/recruitment process please contact EASTBIO

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