Using the inner membrane of Escherichia coli as a scaffold to anchor
enzymes for metabolic flux enhancement
Abstract
Clustering enzymes in the same metabolic pathway is a natural strategy
to enhance productivity. Synthetic protein, RNA and DNA scaffolds have
been designed to artificially cluster multiple enzymes in the cell,
which require complex construction processes and possess limited slots
for target enzymes. We utilized the Escherichia coli inner cell membrane
as a native scaffold to cluster four fatty acid synthases and achieved
to improve the efficiency of fatty acid synthesis in vivo. The
construction strategy is as simple as fusing target enzymes to the
N-terminus or C-terminus of the membrane anchor protein (Lgt), and the
number of anchored enzymes is not restricted. This novel device not only
presents a similar efficiency in clustering multiple enzymes to that of
other artificial scaffolds but also promotes the product secretion,
driving the entire metabolic flux forward and further increasing the
gross yield compared with that in a cytoplasmic scaffold system.