Predicting and testing enzymatic activity

Charlie HarrisonSupervisors: Profs. John Ward &

Christine Orengo

Norcoclaurine• Benzylisoquinoline alkaloids (BIQAs)– group of plant secondary metabolites

• Includes many interesting compounds• Common entry point: norcoclaurine

(S)-norcoclaurine (R)-norcoclaurine

Norcoclaurine• NorcoClaurine Synthase – NCS• Five known examples from three different

species• But BIQAs exist in many more species…• Can we find more NCSs?

Main Project Aims• Bioinformatics– Identify uncharacterised proteins that are likely to

exhibit NCS activity• Lab Work– Express these proteins in E.coli and test

predictions

Bioinformatics• Available data: sequence and structure

• Use these to predict function

Bioinformatics

Reproduced from Orengo, Jones & Thornton 2003 with permission

Bioinformatics• Structural data is better for identifying

functional homologues...

Bioinformatics• Structural data is better for identifying

functional homologues...but is only available for ~1% of sequences

• Use predictions of structural regions – Gene3D• Starting point: Gene3D family of likely

structural relatives• Sequence clustering

Bioinformatics

Lab Work• Design and order the synthetic genes

Wait 3 weeks…

Lab Work

Results

✓ ✓

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Results

Thanks