Targeting of the polyhydroxybutyrate biosynthetic pathway to the plastids of Arabidopsis thaliana results in high levels of polymer accumulation

Journal Article · Tue Dec 20 04:00:00 EST 1994 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

DOI:https://doi.org/10.1073/pnas.91.26.12760· OSTI ID:6707023

Nawrath, C; Poirier, Y; Somerville, C ^[1]

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1. Carnegie Institution of Washington, Stanford, CA (United States)

In the bacterium Alcaligenes eutrophus, three genes encode the enzymes necessary to catalyze the synthesis of poly[(R)-(-)-3-hydroxybutyrate] (PHB) from acetyl-CoA. In order to target these enzymes into the plastids of higher plants, the genes were modified by addition of DNA fragments encoding a pea chloroplast transit peptide, a constitutive plant promoter, and a poly(A) addition sequence. Each of the modified bacterial genes was introduced into Arabidopsis thaliana by Agrobacterium-mediated transformation, and plants containing all three genes were obtained by sexual crosses. These plans accumulated PHB up to 14% of the dry weight as 0.2- to 0.7-[mu]m granules within plastids. In contrast to earlier experiments in which expression of the PHB biosynthetic pathway in the cytoplasm led to a deleterious effect on growth, expression of the PHB biosynthetic pathway in plastids had no obvious effect on the growth or fertility of the transgenic plants and resulted in a 100-fold increase in the amount of PHB in higher plants. The high level of PHB accumulation also suggests that the synthesis of plastid acetyl-CoA is regulated by a mechanism which responds to metabolic demand. 20 refs., 6 figs.

• DOE Contract Number: FG02-94ER20133
• OSTI ID: 6707023
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (United States) Vol. 91:26; ISSN PNASA6; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
550400 -- Genetics
59 BASIC BIOLOGICAL SCIENCES
ARABIDOPSIS
BIOCHEMISTRY
CHEMISTRY
CONTROL
ENZYMES
GENETIC CONTROL
MAGNOLIOPHYTA
MAGNOLIOPSIDA
METABOLISM
ORGANIC COMPOUNDS
PEST CONTROL
PLANTS
PROTEINS
SYNTHESIS