(473a) Invited Talk: Engineering Synthetic Multienzyme Complexes for Spatial Optimization of Biocatalysis

Living cells have evolved to use self-assembled protein structures to spatially organize sequential enzymes to entail facilitated intermediate transfer, enhanced reaction rate and controlled
metabolites flux at branched metabolic nodes. Examples include
multi-enzyme complexes, metabolons, and microcompartment.
These self-assembled protein reactors inspire devise artificial ones
in engineered biosynthetic systems to gear metabolic flux, thereby
improving product yield. In this work, we developed an interactive
protein cage that can be used as a scaffold for multi-enzyme spatial
organization. In vitro, we show that consecutive enzymes in the
menaquinone biosynthesis with different sizes and shapes can be
targeted to the surface of the engineered protein cage in high
density, yielding spherical, monodispersed and homogenous nano-reactors with superior catalytic properties. Modulated reaction rate
was achieved by altering the distance between attached enzymes.
Using a pair of fluorescent proteins as models, proteins assembled
with the protein nanoparticles in complex intracellular environment
spontaneously. In engineered Escherichia coli, three key enzymes
in mevalonate pathway have been co-localized on the exterior of
the protein cage, leading to an 8.5-fold increase of lycopene
production by streamlining metabolic flux towards its biosynthesis.
This work presents a versatile route to multienzyme spatial
organization for applications in biosynthetic industry and studying
the mechanisms of naturally occurring nano-reactors.