Sam Carr

In our latest preprint we report the unexpected discovery of Epi-STR, an R-stereoselective ortholog of the S-selective canonical Strictosidine synthases (STRs). Found in the rather obscure plant Pogonopus specious. This work was led by my stellar student Clara Morweiser!
#natprod
#PlantScience

Single-molecule dynamics of the TRiC chaperonin system in vivo - Nature Single-particle tracking experiments in intact cells reveal dynamic co- and post-translational interactions of the TRiC–PFD chaperonin complex with client proteins during in vivo protein folding.

Nature research paper: Single-molecule dynamics of the TRiC chaperonin system in vivo

go.nature.com/4qZM3Cn

Protein–Protein Interactions Modulate a Key Branch Point in Monoterpene Indole Alkaloid Biosynthesis Biosynthetic pathways of specialized metabolites utilize protein–protein interactions (PPIs) to facilitate metabolic flux and sequester reactive intermediates. The monoterpene indole alkaloid pathway of Catharanthus roseus contains several metabolic branch points that may be mediated via transient PPIs. We investigated one branch point of this pathway that is responsible for the conversion of the intermediate dehydrosecodine into three possible cyclized alkaloid scaffolds, which act as intermediates en route to medicinally important alkaloids, such as vinblastine. We verified previously observed PPIs between reductase-cyclase pairs and additionally uncovered PPIs between evolutionarily related protein homologues. Through structural analysis of dehydrosecodine cyclases, we identified surface residues that appear to mediate interaction with the upstream reductase. We then demonstrated, via in vitro competition assays, that these residues impact the distribution of downstream products. These results highlight the significance of transient PPIs in the control and regulation of specialized metabolite pathways.

Here, we explore the protein-protein interactions between monoterpene indole alkaloid biosynthetic enzymes. This work was the result of strong effort by Chloe Langley, who Allwin McDonald and I had the privilege to work with. Congrats to the team!

ACS Chemical Biology pubs.acs.org/doi/full/10....