Acyl-acyl carrier protein (Acyl-ACP) thioesterases (TE) hydrolyse
the thioester ligation between the ACP (acyl carrier protein) and
the synthesised acyl chain in fatty acid biosynthesis. Myristic and
palmitic-[ACP] are substrates of the Cuphea lanceolata-derived
enzyme which is encoded by the acyl-[ACP] thioesterase gene
(ClFatB4). As a result of the formation of this enzyme the oil
produced in the seeds of the genetically modified (GM) plants
contains myristic acid (C14:0), and increased levels of palmitic
acid (C16:0).
Myristic and palmitic acids, the fatty acids formed by this enzyme
occur naturally in some plant oils used for human consumption (e.g.
coconut oil). There is currently no evidence pointing at a toxic
effect from either the enzyme or the new metabolic product.
When used in modern biotechnology the introduced acyl-[ACP]
thiosterase is expected to catalyse a reaction similar to that of
corresponding enzymes occuring naturally in the seeds of other
(wild and cultivated) plant species.
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