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Complete enzyme set for chlorophyll biosynthesis in Escherichia coli.

ABSTRACT: Chlorophylls are essential cofactors for photosynthesis, which sustains global food chains and oxygen production. Billions of tons of chlorophylls are synthesized annually, yet full understanding of chlorophyll biosynthesis has been hindered by the lack of characterization of the Mg-protoporphyrin IX monomethyl ester oxidative cyclase step, which confers the distinctive green color of these pigments. We demonstrate cyclase activity using heterologously expressed enzyme. Next, we assemble a genetic module that encodes the complete chlorophyll biosynthetic pathway and show that it functions in Escherichia coli. Expression of 12 genes converts endogenous protoporphyrin IX into chlorophyll a, turning E. coli cells green. Our results delineate a minimum set of enzymes required to make chlorophyll and establish a platform for engineering photosynthesis in a heterotrophic model organism.

SUBMITTER: Chen GE

PROVIDER: S-EPMC5787379 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Complete enzyme set for chlorophyll biosynthesis in Escherichia coli.

Chen Guangyu E GE Canniffe Daniel P DP Barnett Samuel F H SFH Hollingshead Sarah S Brindley Amanda A AA Vasilev Cvetelin C Bryant Donald A DA Hunter C Neil CN

Science advances 20180126 1

Chlorophylls are essential cofactors for photosynthesis, which sustains global food chains and oxygen production. Billions of tons of chlorophylls are synthesized annually, yet full understanding of chlorophyll biosynthesis has been hindered by the lack of characterization of the Mg-protoporphyrin IX monomethyl ester oxidative cyclase step, which confers the distinctive green color of these pigments. We demonstrate cyclase activity using heterologously expressed enzyme. Next, we assemble a genet ...[more]

PMID: 29387799

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